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  • Implement date picker and time picker in button click and store in edit text boxes

    - by user3597791
    Hi I am trying to implement a date picker and time picker in button click and store in edit text boxes. I have tried numerous things but since i suck at coding I cant get any of them to work. Please find my class and xml below and i would be grateful for any help import android.app.Activity; import android.content.Intent; import android.database.Cursor; import android.graphics.BitmapFactory; import android.net.Uri; import android.os.Bundle; import android.provider.MediaStore; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.ImageView; import android.widget.Toast; public class NewEvent extends Activity { private static int RESULT_LOAD_IMAGE = 1; private EventHandler handler; private String picturePath = ""; private String name; private String place; private String date; private String time; private String photograph; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.new_event); handler = new EventHandler(getApplicationContext()); ImageView iv_user_photo = (ImageView) findViewById(R.id.iv_user_photo); iv_user_photo.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI); startActivityForResult(intent, RESULT_LOAD_IMAGE); } }); Button btn_add = (Button) findViewById(R.id.btn_add); btn_add.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { EditText et_name = (EditText) findViewById(R.id.et_name); name = et_name.getText().toString(); EditText et_place = (EditText) findViewById(R.id.et_place); place = et_place.getText().toString(); EditText et_date = (EditText) findViewById(R.id.et_date); date = et_date.getText().toString(); EditText et_time = (EditText) findViewById(R.id.et_time); time = et_time.getText().toString(); ImageView iv_photograph = (ImageView) findViewById(R.id.iv_user_photo); photograph = picturePath; Event event = new Event(); event.setName(name); event.setPlace(place); event.setDate(date); event.setTime(time); event.setPhotograph(photograph); Boolean added = handler.addEventDetails(event); if(added){ Intent intent = new Intent(NewEvent.this, MainEvent.class); startActivity(intent); }else{ Toast.makeText(getApplicationContext(), "Event data not added. Please try again", Toast.LENGTH_LONG).show(); } } }); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) { Uri imageUri = data.getData(); String[] filePathColumn = { MediaStore.Images.Media.DATA }; Cursor cursor = getContentResolver().query(imageUri, filePathColumn, null, null, null); cursor.moveToFirst(); int columnIndex = cursor.getColumnIndex(filePathColumn[0]); picturePath = cursor.getString(columnIndex); cursor.close(); Here is my xml: <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:padding="10dp"> <TextView android:id="@+id/tv_new_event_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Add New Event" android:textAppearance="?android:attr/textAppearanceLarge" android:layout_alignParentTop="true" /> <Button android:id="@+id/btn_add" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Add Event" android:layout_alignParentBottom="true" /> <ScrollView android:layout_width="match_parent" android:layout_height="match_parent" android:layout_below="@id/tv_new_event_title" android:layout_above="@id/btn_add"> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="vertical"> <ImageView android:id="@+id/iv_user_photo" android:src="@drawable/add_user_icon" android:layout_width="100dp" android:layout_height="100dp"/> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Event:" /> <EditText android:id="@+id/et_name" android:layout_width="match_parent" android:layout_height="wrap_content" android:ems="10" android:inputType="text" > <requestFocus /> </EditText> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Place:" /> <EditText android:id="@+id/et_place" android:layout_width="match_parent" android:layout_height="wrap_content" android:ems="10" android:inputType="text" > <requestFocus /> </EditText> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Date:" /> <EditText android:id="@+id/et_date" android:layout_width="match_parent" android:layout_height="wrap_content" android:ems="10" android:inputType="date" /> <Button android:id="@+id/button" style="?android:attr/buttonStyleSmall" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <requestFocus /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Time:" /> <EditText android:id="@+id/et_time" android:layout_width="match_parent" android:layout_height="wrap_content" android:ems="10" android:inputType="time" /> <Button android:id="@+id/button1" style="?android:attr/buttonStyleSmall" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button1" /> <requestFocus /> </LinearLayout> </ScrollView> </RelativeLayout>

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  • JPA behaviour...

    - by Marcel
    Hi I have some trouble understanding a JPA behaviour. Mabye someone could give me a hint. Situation: Product entity: @Entity public class Product implements Serializable { ... @OneToMany(mappedBy="product", fetch=FetchType.EAGER) private List<ProductResource> productResources = new ArrayList<ProductResource>(); .... public List<ProductResource> getProductResources() { return productResources; } public boolean equals(Object obj) { if (obj == this) return true; if (obj == null) return false; if (!(obj instanceof Product)) return false; Product p = (Product) obj; return p.productId == productId; } } Resource entity: @Entity public class Resource implements Serializable { ... @OneToMany(mappedBy="resource", fetch=FetchType.EAGER) private List<ProductResource> productResources = new ArrayList<ProductResource>(); ... public void setProductResource(List<ProductResource> productResource) { this.productResources = productResource; } public List<ProductResource> getProductResources() { return productResources; } public boolean equals(Object obj) { if (obj == this) return true; if (obj == null) return false; if (!(obj instanceof Resource)) return false; Resource r = (Resource) obj; return (long)resourceId==(long)r.resourceId; } } ProductResource Entity: This is a JoinTable (association class) with additional properties (amount). It maps Product and Resources. @Entity public class ProductResource implements Serializable { ... @JoinColumn(nullable=false, updatable=false) @ManyToOne(fetch=FetchType.EAGER, cascade=CascadeType.PERSIST) private Product product; @JoinColumn(nullable=false, updatable=false) @ManyToOne(fetch=FetchType.EAGER, cascade=CascadeType.PERSIST) private Resource resource; private int amount; public void setProduct(Product product) { this.product = product; if(!product.getProductResources().contains((this))){ product.getProductResources().add(this); } } public Product getProduct() { return product; } public void setResource(Resource resource) { this.resource = resource; if(!resource.getProductResources().contains((this))){ resource.getProductResources().add(this); } } public Resource getResource() { return resource; } ... public boolean equals(Object obj) { if (obj == this) return true; if (obj == null) return false; if (!(obj instanceof ProductResource)) return false; ProductResource pr = (ProductResource) obj; return (long)pr.productResourceId == (long)productResourceId; } } This is the Session Bean (running on glassfish). @Stateless(mappedName="PersistenceManager") public class PersistenceManagerBean implements PersistenceManager { @PersistenceContext(unitName = "local_mysql") private EntityManager em; public Object create(Object entity) { em.persist(entity); return entity; } public void delete(Object entity) { em.remove(em.merge(entity)); } public Object retrieve(Class entityClass, Long id) { Object entity = em.find(entityClass, id); return entity; } public void update(Object entity) { em.merge(entity); } } I call the session Bean from a java client: public class Start { public static void main(String[] args) throws NamingException { PersistenceManager pm = (PersistenceManager) new InitialContext().lookup("java:global/BackITServer/PersistenceManagerBean"); ProductResource pr = new ProductResource(); Product p = new Product(); Resource r = new Resource(); pr.setProduct(p); pr.setResource(r); ProductResource pr_stored = (ProductResource) pm.create(pr); pm.delete(pr_stored); Product p_ret = (Product) pm.retrieve(Product.class, pr_stored.getProduct().getProductId()); // prints out true ???????????????????????????????????? System.out.println(p_ret.getProductResources().contains(pr_stored)); } } So here comes my problem. Why is the ProductResource entity still in the List productResources(see code above). The productResource tuple in the db is gone after the deletion and I do newly retrieve the Product entity. If I understood right every method call of the client happens in a new persistence context, but here i obviously get back the non-refreshed product object!? Any help is appreciated Thanks Marcel

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  • testing dao with hibernate genericdao pattern with spring.Headache

    - by black sensei
    Hello good fellas! in my journey of learning hibernate i came across an article on hibernate site. i' learning spring too and wanted to do certain things to discover the flexibility of spring by letting you implement you own session.yes i don't want to use the hibernateTemplate(for experiment). and i'm now having a problem and even the test class.I followed the article on the hibernate site especially the section an "implementation with hibernate" so we have the generic dao interface : public interface GenericDAO<T, ID extends Serializable> { T findById(ID id, boolean lock); List<T> findAll(); List<T> findByExample(T exampleInstance); T makePersistent(T entity); void makeTransient(T entity); } it's implementation in an abstract class that is the same as the one on the web site.Please refer to it from the link i provide.i'll like to save this post to be too long now come my dao's messagedao interface package com.project.core.dao; import com.project.core.model.MessageDetails; import java.util.List; public interface MessageDAO extends GenericDAO<MessageDetails, Long>{ //Message class is on of my pojo public List<Message> GetAllByStatus(String status); } its implementation is messagedaoimpl: public class MessageDAOImpl extends GenericDAOImpl <Message, Long> implements MessageDAO { // mySContainer is an interface which my HibernateUtils implement mySContainer sessionManager; /** * */ public MessageDAOImpl(){} /** * * @param sessionManager */ public MessageDAOImpl(HibernateUtils sessionManager){ this.sessionManager = sessionManager; } //........ plus other methods } here is my HibernatUtils public class HibernateUtils implements SessionContainer { private final SessionFactory sessionFactory; private Session session; public HibernateUtils() { this.sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory(); } public HibernateUtils(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; } /** * * this is the function that return a session.So i'm free to implements any type of session in here. */ public Session requestSession() { // if (session != null || session.isOpen()) { // return session; // } else { session = sessionFactory.openSession(); // } return session; } } So in my understanding while using spring(will provide the conf), i'ld wire sessionFactory to my HiberbernateUtils and then wire its method RequestSession to the Session Property of the GenericDAOImpl (the one from the link provided). here is my spring config core.xml <bean id="sessionManager" class="com.project.core.dao.hibernate.HibernateUtils"> <constructor-arg ref="sessionFactory" /> </bean> <bean id="messageDao" class="com.project.core.dao.hibernate.MessageDAOImpl"> <constructor-arg ref="sessionManager"/> </bean> <bean id="genericDAOimpl" class="com.project.core.dao.GenericDAO"> <property name="session" ref="mySession"/> </bean> <bean id="mySession" factory-bean="com.project.core.dao.SessionContainer" factory-method="requestSession"/> now my test is this public class MessageDetailsDAOImplTest extends AbstractDependencyInjectionSpringContextTests{ HibernateUtils sessionManager = (HibernateUtils) applicationContext.getBean("sessionManager"); MessageDAO messagedao =(MessageDAO) applicationContext.getBean("messageDao"); static Message[] message = new Message[] { new Message("text",1,"test for dummies 1","1234567890","Pending",new Date()), new Message("text",2,"test for dummies 2","334455669990","Delivered",new Date()) }; public MessageDAOImplTest() { } @Override protected String[] getConfigLocations(){ return new String[]{"file:src/main/resources/core.xml"}; } @Test public void testMakePersistent() { System.out.println("MakePersistent"); messagedao.makePersistent(message[0]); Session session = sessionManager.RequestSession(); session.beginTransaction(); MessageDetails fromdb = ( Message) session.load(Message.class, message[0].getMessageId()); assertEquals(fromdb.getMessageId(), message[0].getMessageId()); assertEquals(fromdb.getDateSent(),message.getDateSent()); assertEquals(fromdb.getGlobalStatus(),message.getGlobalStatus()); assertEquals(fromdb.getNumberOfPages(),message.getNumberOfPages()); } i'm having this error exception in constructor testMakePersistent(java.lang.NullPointerException at com.project.core.dao.hibernate.MessageDAOImplTest) with this stack : at com.project.core.dao.hibernate.MessageDAOImplTest.(MessageDAOImplTest.java:28) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at junit.framework.TestSuite.createTest(TestSuite.java:61) at junit.framework.TestSuite.addTestMethod(TestSuite.java:283) at junit.framework.TestSuite.(TestSuite.java:146) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:481) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:1031) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:888) )) How to actually make this one work.I know this is a lot to stuffs and i'm thanking you for reading it.Please give me a solution.How would you do this? thanks

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  • Problem with Variable Scoping in Rebol's Object

    - by Rebol Tutorial
    I have modified the rebodex app so that it can be called from rebol's console any time by typing rebodex. To show the title of the app, I need to store it in app-title: system/script/header/title so tha it could be used later in view/new/title dex reform [self/app-title version] That works but as you can see I have named the var name "app-title", but if I use "title" instead, the window caption would show weird stuff (vid code). Why ? REBOL [ Title: "Rebodex" Date: 23-May-2010 Version: 2.1.1 File: %rebodex.r Author: "Carl Sassenrath" Modification: "Rebtut" Purpose: "A simple but useful address book contact database." Email: %carl--rebol--com library: [ level: 'intermediate platform: none type: 'tool domain: [file-handling DB GUI] tested-under: none support: none license: none see-also: none ] ] rebodex.context: context [ app-title: system/script/header/title version: system/script/header/version set 'rebodex func[][ names-path: %names.r ;data file name-list: none fields: [name company title work cell home car fax web email smail notes updat] names: either exists? names-path [load names-path][ [[name "Carl Sassenrath" title "Founder" company "REBOL Technologies" email "%carl--rebol--com" web "http://www.rebol.com"]] ] brws: [ if not empty? web/text [ if not find web/text "http://" [insert web/text "http://"] error? try [browse web/text] ] ] dial: [request [rejoin ["Dial number for " name/text "? (Not implemented.)"] "Dial" "Cancel"]] dex-styles: stylize [ lab: label 60x20 right bold middle font-size 11 btn: button 64x20 font-size 11 edge [size: 1x1] fld: field 200x20 font-size 11 middle edge [size: 1x1] inf: info font-size 11 middle edge [size: 1x1] ari: field wrap font-size 11 edge [size: 1x1] with [flags: [field tabbed]] ] dex-pane1: layout/offset [ origin 0 space 2x0 across styles dex-styles lab "Name" name: fld bold return lab "Title" title: fld return lab "Company" company: fld return lab "Email" email: fld return lab "Web" brws web: fld return lab "Address" smail: ari 200x72 return lab "Updated" updat: inf 200x20 return ] 0x0 updat/flags: none dex-pane2: layout/offset [ origin 0 space 2x0 across styles dex-styles lab "Work #" dial work: fld 140 return lab "Home #" dial home: fld 140 return lab "Cell #" dial cell: fld 140 return lab "Alt #" dial car: fld 140 return lab "Fax #" fax: fld 140 return lab "Notes" notes: ari 140x72 return pad 136x1 btn "Close" #"^q" [store-entry save-file unview] ] 0x0 dex: layout [ origin 8x8 space 0x1 styles dex-styles srch: fld 196x20 bold across rslt: list 180x150 [ nt: txt 178x15 middle font-size 11 [ store-entry curr: cnt find-name nt/text update-entry unfocus show dex ] ] supply [ cnt: count + scroll-off face/text: "" face/color: snow if not n: pick name-list cnt [exit] face/text: select n 'name face/font/color: black if curr = cnt [face/color: system/view/vid/vid-colors/field-select] ] sl: slider 16x150 [scroll-list] return return btn "New" #"^n" [new-name] btn "Del" #"^d" [delete-name unfocus update-entry search-all show dex] btn "Sort" [sort names sort name-list show rslt] return at srch/offset + (srch/size * 1x0) bx1: box dex-pane1/size bx2: box dex-pane2/size return ] bx1/pane: dex-pane1/pane bx2/pane: dex-pane2/pane rslt/data: [] this-name: first names name-list: copy names curr: none search-text: "" scroll-off: 0 srch/feel: make srch/feel [ redraw: func [face act pos][ face/color: pick face/colors face system/view/focal-face if all [face = system/view/focal-face face/text search-text] [ search-text: copy face/text search-all if 1 = length? name-list [this-name: first name-list update-entry show dex] ] ] ] update-file: func [data] [ set [path file] split-path names-path if not exists? path [make-dir/deep path] write names-path data ] save-file: has [buf] [ buf: reform [{REBOL [Title: "Name Database" Date:} now "]^/[^/"] foreach n names [repend buf [mold n newline]] update-file append buf "]" ] delete-name: does [ remove find/only names this-name if empty? names [append-empty] save-file new-name ] clean-names: function [][n][ forall names [ if any [empty? first names none? n: select first names 'name empty? n][ remove names ] ] names: head names ] search-all: function [] [ent flds] [ clean-names clear name-list flds: [name] either empty? search-text [insert name-list names][ foreach nam names [ foreach word flds [ if all [ent: select nam word find ent search-text][ append/only name-list nam break ] ] ] ] scroll-off: 0 sl/data: 0 resize-drag scroll-list curr: none show [rslt sl] ] new-name: does [ store-entry clear-entry search-all append-empty focus name ; update-entry ] append-empty: does [append/only names this-name: copy []] find-name: function [str][] [ foreach nam names [ if str = select nam 'name [ this-name: nam break ] ] ] store-entry: has [val ent flag] [ flag: 0 if not empty? trim name/text [ foreach word fields [ val: trim get in get word 'text either ent: select this-name word [ if ent val [insert clear ent val flag: flag + 1] ][ if not empty? val [repend this-name [word copy val] flag: flag + 1] ] if flag = 1 [flag: 2 updat/text: form now] ] if not zero? flag [save-file] ] ] update-entry: does [ foreach word fields [ insert clear get in get word 'text any [select this-name word ""] ] show rslt ] clear-entry: does [ clear-fields bx1 clear-fields bx2 updat/text: form now unfocus show dex ] show-names: does [ clear rslt/data foreach n name-list [ if n/name [append rslt/data n/name] ] show rslt ] scroll-list: does [ scroll-off: max 0 to-integer 1 + (length? name-list) - (100 / 16) * sl/data show rslt ] do resize-drag: does [sl/redrag 100 / max 1 (16 * length? name-list)] center-face dex new-name focus srch show-names view/new/title dex reform [app-title version] insert-event-func [ either all [event/type = 'close event/face = dex][ store-entry unview ][event] ] do-events ] ]

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  • storing data in a database using edit text and button

    - by user1841444
    Hai im trying to Insert data into database using EditText and Button i have created. Im stuck at Activity part of the Code.I unbale to proceed how to write the Onclick action part for Button and EditText part Please help me. Im new to android DBAdapter.java package com.example.database1; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; import android.util.Log; public class DBAdapter { public static final String KEY_ROWID = "_id"; public static final String KEY_ISBN = "isbn"; public static final String KEY_TITLE = "title"; public static final String KEY_PUBLISHER = "publisher"; private static final String TAG = "DBAdapter"; private static final String DATABASE_NAME = "books"; private static final String DATABASE_TABLE = "titles"; private static final int DATABASE_VERSION = 1; private static final String DATABASE_CREATE = "create table titles (_id integer primary key autoincrement, " + "isbn text not null, title text not null, " + "publisher text not null);"; private final Context context; private DatabaseHelper DBHelper; private SQLiteDatabase db; public DBAdapter(Context ctx) { this.context = ctx; DBHelper = new DatabaseHelper(context); } private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(DATABASE_CREATE); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS titles"); onCreate(db); } } //---opens the database--- public DBAdapter open() throws SQLException { db = DBHelper.getWritableDatabase(); return this; } //---closes the database--- public void close() { DBHelper.close(); } //---insert a title into the database--- public long insertTitle(String isbn, String title, String publisher) { ContentValues initialValues = new ContentValues(); initialValues.put(KEY_ISBN, isbn); initialValues.put(KEY_TITLE, title); initialValues.put(KEY_PUBLISHER, publisher); return db.insert(DATABASE_TABLE, null, initialValues); } //---deletes a particular title--- public boolean deleteTitle(long rowId) { return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0; } //---retrieves all the titles--- public Cursor getAllTitles() { return db.query(DATABASE_TABLE, new String[] { KEY_ROWID, KEY_ISBN, KEY_TITLE, KEY_PUBLISHER}, null, null, null, null, null); } //---retrieves a particular title--- public Cursor getTitle(long rowId) throws SQLException { Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] { KEY_ROWID, KEY_ISBN, KEY_TITLE, KEY_PUBLISHER }, KEY_ROWID + "=" + rowId, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } //---updates a title--- public boolean updateTitle(long rowId, String isbn, String title, String publisher) { ContentValues args = new ContentValues(); args.put(KEY_ISBN, isbn); args.put(KEY_TITLE, title); args.put(KEY_PUBLISHER, publisher); return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0; } } DatabaseActivity.java package com.example.database1; import android.os.Bundle; import android.app.Activity; import android.database.Cursor; import android.view.Menu; import android.widget.Toast; public class DatabaseActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_database); DBAdapter db=new DBAdapter(this); db.open(); } } activity_database.xml: <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent"> <EditText android:id="@+id/edit1" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <EditText android:id="@+id/edit2" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <EditText android:id="@+id/edit3" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <Button android:id="@+id/submit" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </LinearLayout>

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  • How to filter Backbone.js Collection and Rerender App View?

    - by Jeremy H.
    Is is a total Backbone.js noob question. I am working off of the ToDo Backbone.js example trying to build out a fairly simple single app interface. While the todo project is more about user input, this app is more about filtering the data based on the user options (click events). I am completely new to Backbone.js and Mongoose and have been unable to find a good example of what I am trying to do. I have been able to get my api to pull the data from the MongoDB collection and drop it into the Backbone.js collection which renders it in the app. What I cannot for the life of me figure out how to do is filter that data and re-render the app view. I am trying to filter by the "type" field in the document. Here is my script: (I am totally aware of some major refactoring needed, I am just rapid prototyping a concept.) $(function() { window.Job = Backbone.Model.extend({ idAttribute: "_id", defaults: function() { return { attachments: false } } }); window.JobsList = Backbone.Collection.extend({ model: Job, url: '/api/jobs', leads: function() { return this.filter(function(job){ return job.get('type') == "Lead"; }); } }); window.Jobs = new JobsList; window.JobView = Backbone.View.extend({ tagName: "div", className: "item", template: _.template($('#item-template').html()), initialize: function() { this.model.bind('change', this.render, this); this.model.bind('destroy', this.remove, this); }, render: function() { $(this.el).html(this.template(this.model.toJSON())); this.setText(); return this; }, setText: function() { var month=new Array(); month[0]="Jan"; month[1]="Feb"; month[2]="Mar"; month[3]="Apr"; month[4]="May"; month[5]="Jun"; month[6]="Jul"; month[7]="Aug"; month[8]="Sep"; month[9]="Oct"; month[10]="Nov"; month[11]="Dec"; var title = this.model.get('title'); var description = this.model.get('description'); var datemonth = this.model.get('datem'); var dateday = this.model.get('dated'); var jobtype = this.model.get('type'); var jobstatus = this.model.get('status'); var amount = this.model.get('amount'); var paymentstatus = this.model.get('paymentstatus') var type = this.$('.status .jobtype'); var status = this.$('.status .jobstatus'); this.$('.title a').text(title); this.$('.description').text(description); this.$('.date .month').text(month[datemonth]); this.$('.date .day').text(dateday); type.text(jobtype); status.text(jobstatus); if(amount > 0) this.$('.paymentamount').text(amount) if(paymentstatus) this.$('.paymentstatus').text(paymentstatus) if(jobstatus === 'New') { status.addClass('new'); } else if (jobstatus === 'Past Due') { status.addClass('pastdue') }; if(jobtype === 'Lead') { type.addClass('lead'); } else if (jobtype === '') { type.addClass(''); }; }, remove: function() { $(this.el).remove(); }, clear: function() { this.model.destroy(); } }); window.AppView = Backbone.View.extend({ el: $("#main"), events: { "click #leads .highlight" : "filterLeads" }, initialize: function() { Jobs.bind('add', this.addOne, this); Jobs.bind('reset', this.addAll, this); Jobs.bind('all', this.render, this); Jobs.fetch(); }, addOne: function(job) { var view = new JobView({model: job}); this.$("#activitystream").append(view.render().el); }, addAll: function() { Jobs.each(this.addOne); }, filterLeads: function() { // left here, this event fires but i need to figure out how to filter the activity list. } }); window.App = new AppView; });

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  • I get java.lang.NullPointerException when trying to get the contents of the database in Android

    - by ncountr
    I am using 8 EditText boxes from the NewCard.xml from which i am taking the values and when the save button is pressed i am storing the values into a database, in the same process of saving i am trying to get the values and present them into 8 different TextView boxes on the main.xml file and when i press the button i get an FC from the emulator and the resulting error is java.lang.NullPointerException. If Some 1 could help me that would be great, since i have never used databases and this is my first application for android and this is the only thing keepeng me to complete the whole thing and publish it on the market like a free app. Here's the full code from NewCard.java. public class NewCard extends Activity { private static String[] FROM = { _ID, FIRST_NAME, LAST_NAME, POSITION, POSTAL_ADDRESS, PHONE_NUMBER, FAX_NUMBER, MAIL_ADDRESS, WEB_ADDRESS}; private static String ORDER_BY = FIRST_NAME; private CardsData cards; EditText First_Name; EditText Last_Name; EditText Position; EditText Postal_Address; EditText Phone_Number; EditText Fax_Number; EditText Mail_Address; EditText Web_Address; Button New_Cancel; Button New_Save; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.newcard); cards = new CardsData(this); //Define the Cancel Button in NewCard Activity New_Cancel = (Button) this.findViewById(R.id.new_cancel_button); //Define the Cancel Button Activity/s New_Cancel.setOnClickListener ( new OnClickListener() { public void onClick(View arg0) { NewCancelDialog(); } } );//End of the Cancel Button Activity/s //Define the Save Button in NewCard Activity New_Save = (Button) this.findViewById(R.id.new_save_button); //Define the EditText Fields to Get Their Values Into the Database First_Name = (EditText) this.findViewById(R.id.new_first_name); Last_Name = (EditText) this.findViewById(R.id.new_last_name); Position = (EditText) this.findViewById(R.id.new_position); Postal_Address = (EditText) this.findViewById(R.id.new_postal_address); Phone_Number = (EditText) this.findViewById(R.id.new_phone_number); Fax_Number = (EditText) this.findViewById(R.id.new_fax_number); Mail_Address = (EditText) this.findViewById(R.id.new_mail_address); Web_Address = (EditText) this.findViewById(R.id.new_web_address); //Define the Save Button Activity/s New_Save.setOnClickListener ( new OnClickListener() { public void onClick(View arg0) { //Add Code For Saving The Attributes Into The Database try { addCard(First_Name.getText().toString(), Last_Name.getText().toString(), Position.getText().toString(), Postal_Address.getText().toString(), Integer.parseInt(Phone_Number.getText().toString()), Integer.parseInt(Fax_Number.getText().toString()), Mail_Address.getText().toString(), Web_Address.getText().toString()); Cursor cursor = getCard(); showCard(cursor); } finally { cards.close(); NewCard.this.finish(); } } } );//End of the Save Button Activity/s } //======================================================================================// //DATABASE FUNCTIONS private void addCard(String firstname, String lastname, String position, String postaladdress, int phonenumber, int faxnumber, String mailaddress, String webaddress) { // Insert a new record into the Events data source. // You would do something similar for delete and update. SQLiteDatabase db = cards.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(FIRST_NAME, firstname); values.put(LAST_NAME, lastname); values.put(POSITION, position); values.put(POSTAL_ADDRESS, postaladdress); values.put(PHONE_NUMBER, phonenumber); values.put(FAX_NUMBER, phonenumber); values.put(MAIL_ADDRESS, mailaddress); values.put(WEB_ADDRESS, webaddress); db.insertOrThrow(TABLE_NAME, null, values); } private Cursor getCard() { // Perform a managed query. The Activity will handle closing // and re-querying the cursor when needed. SQLiteDatabase db = cards.getReadableDatabase(); Cursor cursor = db.query(TABLE_NAME, FROM, null, null, null, null, ORDER_BY); startManagingCursor(cursor); return cursor; } private void showCard(Cursor cursor) { // Stuff them all into a big string long id = 0; String firstname = null; String lastname = null; String position = null; String postaladdress = null; long phonenumber = 0; long faxnumber = 0; String mailaddress = null; String webaddress = null; while (cursor.moveToNext()) { // Could use getColumnIndexOrThrow() to get indexes id = cursor.getLong(0); firstname = cursor.getString(1); lastname = cursor.getString(2); position = cursor.getString(3); postaladdress = cursor.getString(4); phonenumber = cursor.getLong(5); faxnumber = cursor.getLong(6); mailaddress = cursor.getString(7); webaddress = cursor.getString(8); } // Display on the screen add for each textView TextView ids = (TextView) findViewById(R.id.id); TextView fn = (TextView) findViewById(R.id.firstname); TextView ln = (TextView) findViewById(R.id.lastname); TextView pos = (TextView) findViewById(R.id.position); TextView pa = (TextView) findViewById(R.id.postaladdress); TextView pn = (TextView) findViewById(R.id.phonenumber); TextView fxn = (TextView) findViewById(R.id.faxnumber); TextView ma = (TextView) findViewById(R.id.mailaddress); TextView wa = (TextView) findViewById(R.id.webaddress); ids.setText(String.valueOf(id)); fn.setText(String.valueOf(firstname)); ln.setText(String.valueOf(lastname)); pos.setText(String.valueOf(position)); pa.setText(String.valueOf(postaladdress)); pn.setText(String.valueOf(phonenumber)); fxn.setText(String.valueOf(faxnumber)); ma.setText(String.valueOf(mailaddress)); wa.setText(String.valueOf(webaddress)); } //======================================================================================// //Define the Dialog that alerts you when you press the Cancel button private void NewCancelDialog() { new AlertDialog.Builder(this) .setMessage("Are you sure you want to cancel?") .setTitle("Cancel") .setCancelable(false) .setPositiveButton("Yes", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { NewCard.this.finish(); } }) .setNegativeButton("No", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { dialog.cancel(); } }) .show(); }//End of the Cancel Dialog }

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  • How to simulate browser file upload with HttpWebRequest

    - by cucicov
    Hi, guys, first of all thanks for your contributions, I've found great responses here. Yet I've ran into a problem I can't figure out and if someone could provide any help, it would be greatly appreciated. I'm developing this application in C# that could upload an image from computer to user photoblog. For this I'm usig pixelpost platform for photoblogs that is written mainly in PHP. I've searched here and on other web pages, but the exmples provided there didn't work for me. Here is what I used in my example: (http://stackoverflow.com/questions/566462/upload-files-with-httpwebrequest-multipart-form-data) and (http://bytes.com/topic/c-sharp/answers/268661-how-upload-file-via-c-code) Once it is ready I will make it available for free on the internet and maybe also create a windows mobile version of it, since I'm a fan of pixelpost. here is the code I've used: string formUrl = "http://localhost/pixelpost/admin/index.php?x=login"; string formParams = string.Format("user={0}&password={1}", "user-String", "password-String"); string cookieHeader; HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(formUrl); req.ContentType = "application/x-www-form-urlencoded"; req.Method = "POST"; req.AllowAutoRedirect = false; byte[] bytes = Encoding.ASCII.GetBytes(formParams); req.ContentLength = bytes.Length; using (Stream os = req.GetRequestStream()) { os.Write(bytes, 0, bytes.Length); } HttpWebResponse resp = (HttpWebResponse)req.GetResponse(); cookieHeader = resp.Headers["Set-Cookie"]; string pageSource; using (StreamReader sr = new StreamReader(resp.GetResponseStream())) { pageSource = sr.ReadToEnd(); Console.WriteLine(); } string getUrl = "http://localhost/pixelpost/admin/index.php"; HttpWebRequest getRequest = (HttpWebRequest)HttpWebRequest.Create(getUrl); getRequest.Headers.Add("Cookie", cookieHeader); HttpWebResponse getResponse = (HttpWebResponse)getRequest.GetResponse(); using (StreamReader sr = new StreamReader(getResponse.GetResponseStream())) { pageSource = sr.ReadToEnd(); } // end first part: login to admin panel long length = 0; string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x"); HttpWebRequest httpWebRequest2 = (HttpWebRequest)WebRequest.Create("http://localhost/pixelpost/admin/index.php?x=save"); httpWebRequest2.ContentType = "multipart/form-data; boundary=" + boundary; httpWebRequest2.Method = "POST"; httpWebRequest2.AllowAutoRedirect = false; httpWebRequest2.KeepAlive = false; httpWebRequest2.Credentials = System.Net.CredentialCache.DefaultCredentials; httpWebRequest2.Headers.Add("Cookie", cookieHeader); Stream memStream = new System.IO.MemoryStream(); byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n"); string formdataTemplate = "\r\n--" + boundary + "\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}"; string formitem = string.Format(formdataTemplate, "headline", "image-name"); byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem); memStream.Write(formitembytes, 0, formitembytes.Length); memStream.Write(boundarybytes, 0, boundarybytes.Length); string headerTemplate = "\r\nContent-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: application/octet-stream\r\n\r\n"; string header = string.Format(headerTemplate, "userfile", "path-to-the-local-file"); byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header); memStream.Write(headerbytes, 0, headerbytes.Length); FileStream fileStream = new FileStream("path-to-the-local-file", FileMode.Open, FileAccess.Read); byte[] buffer = new byte[1024]; int bytesRead = 0; while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0) { memStream.Write(buffer, 0, bytesRead); } memStream.Write(boundarybytes, 0, boundarybytes.Length); fileStream.Close(); httpWebRequest2.ContentLength = memStream.Length; Stream requestStream = httpWebRequest2.GetRequestStream(); memStream.Position = 0; byte[] tempBuffer = new byte[memStream.Length]; memStream.Read(tempBuffer, 0, tempBuffer.Length); memStream.Close(); requestStream.Write(tempBuffer, 0, tempBuffer.Length); requestStream.Close(); WebResponse webResponse2 = httpWebRequest2.GetResponse(); Stream stream2 = webResponse2.GetResponseStream(); StreamReader reader2 = new StreamReader(stream2); Console.WriteLine(reader2.ReadToEnd()); webResponse2.Close(); httpWebRequest2 = null; webResponse2 = null; and also here is the PHP: (http://dl.dropbox.com/u/3149888/index.php) and (http://dl.dropbox.com/u/3149888/new_image.php) the mandatory fields are headline and userfile so I can't figure out where the mistake is, as the format sent in right. I'm guessing there is something wrong with the octet-stream sent to the form. Maybe it's a stupid mistake I wasn't able to trace, in any case, if you could help me that would mean a lot. thanks,

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  • Customized listfield with image displaying from a url

    - by arunabha
    I am displaying a customized list field with text on the right side and image on the left side.The image comes from a URL dynamically.Initially i am placing a blank image on the left of the list field,then call URLBitmapField class's setURL method,which actually does the processing and places the processed image on top of the blank image.The image gets displayed on the list field,but to see that processed image i need to press any key or click on the list field items.I want the processed image to be displayed automatically in the list field after the processing.Can anyone tell me where i am getting wrong? import java.util.Vector; import net.rim.device.api.system.Bitmap; import net.rim.device.api.system.Display; import net.rim.device.api.ui.ContextMenu; import net.rim.device.api.ui.DrawStyle; import net.rim.device.api.ui.Field; import net.rim.device.api.ui.Font; import net.rim.device.api.ui.Graphics; import net.rim.device.api.ui.Manager; import net.rim.device.api.ui.MenuItem; import net.rim.device.api.ui.UiApplication; import net.rim.device.api.ui.component.BitmapField; import net.rim.device.api.ui.component.Dialog; import net.rim.device.api.ui.component.LabelField; import net.rim.device.api.ui.component.ListField; import net.rim.device.api.ui.component.ListFieldCallback; import net.rim.device.api.ui.component.NullField; import net.rim.device.api.ui.container.FullScreen; import net.rim.device.api.ui.container.MainScreen; import net.rim.device.api.ui.container.VerticalFieldManager; import net.rim.device.api.util.Arrays; import net.rim.device.api.ui.component.ListField; public class TaskListField extends UiApplication { // statics // ------------------------------------------------------------------ public static void main(String[] args) { TaskListField theApp = new TaskListField(); theApp.enterEventDispatcher(); } public TaskListField() { pushScreen(new TaskList()); } } class TaskList extends MainScreen implements ListFieldCallback { private Vector rows; private Bitmap p1; private Bitmap p2; private Bitmap p3; String Task; ListField listnew = new ListField(); private VerticalFieldManager metadataVFM; TableRowManager row; public TaskList() { super(); URLBitmapField artistImgField; listnew.setRowHeight(80); listnew.setCallback(this); rows = new Vector(); for (int x = 0; x <3; x++) { row = new TableRowManager(); artistImgField = new URLBitmapField(Bitmap .getBitmapResource("res/images/bg.jpg")); row.add(artistImgField); String photoURL = "someimagefrmurl.jpg"; Log.info(photoURL); // strip white spaces in the url, which is causing the // images to not display properly for (int i = 0; i < photoURL.length(); i++) { if (photoURL.charAt(i) == ' ') { photoURL = photoURL.substring(0, i) + "%20" + photoURL.substring(i + 1, photoURL.length()); } } Log.info("Processed URL: " + photoURL); artistImgField.setURL(photoURL); LabelField task = new LabelField("Display"); row.add(task); LabelField task1 = new LabelField( "Now Playing" + String.valueOf(x)); Font myFont = Font.getDefault().derive(Font.PLAIN, 12); task1.setFont(myFont); row.add(task1); rows.addElement(row); } listnew.setSize(rows.size()); this.add(listnew); //listnew.invalidate(); } // ListFieldCallback Implementation public void drawListRow(ListField listField, Graphics g, int index, int y, int width) { TableRowManager rowManager = (TableRowManager) rows.elementAt(index); rowManager.drawRow(g, 0, y, width, listnew.getRowHeight()); } protected void drawFocus(Graphics graphics, boolean on) { } private class TableRowManager extends Manager { public TableRowManager() { super(0); } // Causes the fields within this row manager to be layed out then // painted. public void drawRow(Graphics g, int x, int y, int width, int height) { // Arrange the cell fields within this row manager. layout(width, height); // Place this row manager within its enclosing list. setPosition(x, y); // Apply a translating/clipping transformation to the graphics // context so that this row paints in the right area. g.pushRegion(getExtent()); // Paint this manager's controlled fields. subpaint(g); g.setColor(0x00CACACA); g.drawLine(0, 0, getPreferredWidth(), 0); // Restore the graphics context. g.popContext(); } // Arrages this manager's controlled fields from left to right within // the enclosing table's columns. protected void sublayout(int width, int height) { // set the size and position of each field. int fontHeight = Font.getDefault().getHeight(); int preferredWidth = getPreferredWidth(); // start with the Bitmap Field of the priority icon Field field = getField(0); layoutChild(field, 146,80); setPositionChild(field, 0, 0); // set the task name label field field = getField(1); layoutChild(field, preferredWidth - 16, fontHeight + 1); setPositionChild(field, 149, 3); // set the list name label field field = getField(2); layoutChild(field, 150, fontHeight + 1); setPositionChild(field, 149, fontHeight + 6); setExtent(360, 480); } // The preferred width of a row is defined by the list renderer. public int getPreferredWidth() { return listnew.getWidth(); } // The preferred height of a row is the "row height" as defined in the // enclosing list. public int getPreferredHeight() { return listnew.getRowHeight(); } } public Object get(ListField listField, int index) { // TODO Auto-generated method stub return null; } public int getPreferredWidth(ListField listField) { return 0; } public int indexOfList(ListField listField, String prefix, int start) { // TODO Auto-generated method stub return 0; } }

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  • How do I get .NET to garbage collect aggressively?

    - by mmr
    I have an application that is used in image processing, and I find myself typically allocating arrays in the 4000x4000 ushort size, as well as the occasional float and the like. Currently, the .NET framework tends to crash in this app apparently randomly, almost always with an out of memory error. 32mb is not a huge declaration, but if .NET is fragmenting memory, then it's very possible that such large continuous allocations aren't behaving as expected. Is there a way to tell the garbage collector to be more aggressive, or to defrag memory (if that's the problem)? I realize that there's the GC.Collect and GC.WaitForPendingFinalizers calls, and I've sprinkled them pretty liberally through my code, but I'm still getting the errors. It may be because I'm calling dll routines that use native code a lot, but I'm not sure. I've gone over that C++ code, and make sure that any memory I declare I delete, but still I get these C# crashes, so I'm pretty sure it's not there. I wonder if the C++ calls could be interfering with the GC, making it leave behind memory because it once interacted with a native call-- is that possible? If so, can I turn that functionality off? EDIT: Here is some very specific code that will cause the crash. According to this SO question, I do not need to be disposing of the BitmapSource objects here. Here is the naive version, no GC.Collects in it. It generally crashes on iteration 4 to 10 of the undo procedure. This code replaces the constructor in a blank WPF project, since I'm using WPF. I do the wackiness with the bitmapsource because of the limitations I explained in my answer to @dthorpe below as well as the requirements listed in this SO question. public partial class Window1 : Window { public Window1() { InitializeComponent(); //Attempts to create an OOM crash //to do so, mimic minute croppings of an 'image' (ushort array), and then undoing the crops int theRows = 4000, currRows; int theColumns = 4000, currCols; int theMaxChange = 30; int i; List<ushort[]> theList = new List<ushort[]>();//the list of images in the undo/redo stack byte[] displayBuffer = null;//the buffer used as a bitmap source BitmapSource theSource = null; for (i = 0; i < theMaxChange; i++) { currRows = theRows - i; currCols = theColumns - i; theList.Add(new ushort[(theRows - i) * (theColumns - i)]); displayBuffer = new byte[theList[i].Length]; theSource = BitmapSource.Create(currCols, currRows, 96, 96, PixelFormats.Gray8, null, displayBuffer, (currCols * PixelFormats.Gray8.BitsPerPixel + 7) / 8); System.Console.WriteLine("Got to change " + i.ToString()); System.Threading.Thread.Sleep(100); } //should get here. If not, then theMaxChange is too large. //Now, go back up the undo stack. for (i = theMaxChange - 1; i >= 0; i--) { displayBuffer = new byte[theList[i].Length]; theSource = BitmapSource.Create((theColumns - i), (theRows - i), 96, 96, PixelFormats.Gray8, null, displayBuffer, ((theColumns - i) * PixelFormats.Gray8.BitsPerPixel + 7) / 8); System.Console.WriteLine("Got to undo change " + i.ToString()); System.Threading.Thread.Sleep(100); } } } Now, if I'm explicit in calling the garbage collector, I have to wrap the entire code in an outer loop to cause the OOM crash. For me, this tends to happen around x = 50 or so: public partial class Window1 : Window { public Window1() { InitializeComponent(); //Attempts to create an OOM crash //to do so, mimic minute croppings of an 'image' (ushort array), and then undoing the crops for (int x = 0; x < 1000; x++){ int theRows = 4000, currRows; int theColumns = 4000, currCols; int theMaxChange = 30; int i; List<ushort[]> theList = new List<ushort[]>();//the list of images in the undo/redo stack byte[] displayBuffer = null;//the buffer used as a bitmap source BitmapSource theSource = null; for (i = 0; i < theMaxChange; i++) { currRows = theRows - i; currCols = theColumns - i; theList.Add(new ushort[(theRows - i) * (theColumns - i)]); displayBuffer = new byte[theList[i].Length]; theSource = BitmapSource.Create(currCols, currRows, 96, 96, PixelFormats.Gray8, null, displayBuffer, (currCols * PixelFormats.Gray8.BitsPerPixel + 7) / 8); } //should get here. If not, then theMaxChange is too large. //Now, go back up the undo stack. for (i = theMaxChange - 1; i >= 0; i--) { displayBuffer = new byte[theList[i].Length]; theSource = BitmapSource.Create((theColumns - i), (theRows - i), 96, 96, PixelFormats.Gray8, null, displayBuffer, ((theColumns - i) * PixelFormats.Gray8.BitsPerPixel + 7) / 8); GC.WaitForPendingFinalizers();//force gc to collect, because we're in scenario 2, lots of large random changes GC.Collect(); } System.Console.WriteLine("Got to changelist " + x.ToString()); System.Threading.Thread.Sleep(100); } } } If I'm mishandling memory in either scenario, if there's something I should spot with a profiler, let me know. That's a pretty simple routine there. Unfortunately, it looks like @Kevin's answer is right-- this is a bug in .NET and how .NET handles objects larger than 85k. This situation strikes me as exceedingly strange; could Powerpoint be rewritten in .NET with this kind of limitation, or any of the other Office suite applications? 85k does not seem to me to be a whole lot of space, and I'd also think that any program that uses so-called 'large' allocations frequently would become unstable within a matter of days to weeks when using .NET. EDIT: It looks like Kevin is right, this is a limitation of .NET's GC. For those who don't want to follow the entire thread, .NET has four GC heaps: gen0, gen1, gen2, and LOH (Large Object Heap). Everything that's 85k or smaller goes on one of the first three heaps, depending on creation time (moved from gen0 to gen1 to gen2, etc). Objects larger than 85k get placed on the LOH. The LOH is never compacted, so eventually, allocations of the type I'm doing will eventually cause an OOM error as objects get scattered about that memory space. We've found that moving to .NET 4.0 does help the problem somewhat, delaying the exception, but not preventing it. To be honest, this feels a bit like the 640k barrier-- 85k ought to be enough for any user application (to paraphrase this video of a discussion of the GC in .NET). For the record, Java does not exhibit this behavior with its GC.

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  • Click edit button twice in gridview asp.net c# issue

    - by Supriyo Banerjee
    I have a gridview created on a page where I want to provide an edit button for the user to click in. However the issue is the grid view row becomes editable only while clicking the edit button second time. Not sure what is going wrong here, any help would be appreciated. One additional point is my grid view is displayed on the page only on a click of a button and is not there on page_load event hence. Posting the code snippets: //MY Aspx code <Columns> <asp:TemplateField HeaderText="Slice" SortExpression="name"> <ItemTemplate> <asp:Label ID="lblslice" Text='<%# Eval("slice") %>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lblslice" Text='<%# Eval("slice") %>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Metric" SortExpression="Description"> <ItemTemplate> <asp:Label ID="lblmetric" Text='<%# Eval("metric")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lblmetric" Text='<%# Eval("metric")%>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Original" SortExpression="Type"> <ItemTemplate> <asp:Label ID="lbloriginal" Text='<%# Eval("Original")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lbloriginal" Text='<%# Eval("Original")%>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="WOW" SortExpression="Market"> <ItemTemplate> <asp:Label ID="lblwow" Text='<%# Eval("WOW")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lblwow" Text='<%# Eval("WOW")%>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Change" SortExpression="Market" > <ItemTemplate> <asp:Label ID="lblChange" Text='<%# Eval("Change")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="TxtCustomerID" Text='<%# Eval("Change") %> ' runat="server"></asp:TextBox> </EditItemTemplate> </asp:TemplateField> <asp:CommandField HeaderText="Edit" ShowEditButton="True" /> </Columns> </asp:GridView> //My code behind: protected void Page_Load(object sender, EventArgs e) { } public void populagridview1(string slice,string fromdate,string todate,string year) { SqlCommand cmd; SqlDataAdapter da; DataSet ds; cmd = new SqlCommand(); cmd.CommandType = CommandType.StoredProcedure; cmd.CommandText = "usp_geteventchanges"; cmd.Connection = conn; conn.Open(); SqlParameter param1 = new SqlParameter("@slice", slice); cmd.Parameters.Add(param1); SqlParameter param2 = new SqlParameter("@fromdate", fromdate); cmd.Parameters.Add(param2); SqlParameter param3 = new SqlParameter("@todate", todate); cmd.Parameters.Add(param3); SqlParameter param4 = new SqlParameter("@year", year); cmd.Parameters.Add(param4); da = new SqlDataAdapter(cmd); ds = new DataSet(); da.Fill(ds, "Table"); GridView1.DataSource = ds; GridView1.DataBind(); conn.Close(); } protected void ImpactCalc(object sender, EventArgs e) { populagridview1(ddl_slice.SelectedValue, dt_to_integer(Picker1.Text), dt_to_integer(Picker2.Text), Txt_Year.Text); } protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e) { gvEditIndex = e.NewEditIndex; Gridview1.DataBind(); } My page layout This edit screen appears after clicking edit twice.. the grid view gets displayed on hitting the Calculate impact button. The data is from a backend stored procedure which is fired on clicking the Calculate impact button

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  • What is stopping data flow with .NET 3.5 asynchronous System.Net.Sockets.Socket?

    - by TonyG
    I have a .NET 3.5 client/server socket interface using the asynchronous methods. The client connects to the server and the connection should remain open until the app terminates. The protocol consists of the following pattern: send stx receive ack send data1 receive ack send data2 (repeat 5-6 while more data) receive ack send etx So a single transaction with two datablocks as above would consist of 4 sends from the client. After sending etx the client simply waits for more data to send out, then begins the next transmission with stx. I do not want to break the connection between individual exchanges or after each stx/data/etx payload. Right now, after connection, the client can send the first stx, and get a single ack, but I can't put more data onto the wire after that. Neither side disconnects, the socket is still intact. The client code is seriously abbreviated as follows - I'm following the pattern commonly available in online code samples. private void SendReceive(string data) { // ... SocketAsyncEventArgs completeArgs; completeArgs.Completed += new EventHandler<SocketAsyncEventArgs>(OnSend); clientSocket.SendAsync(completeArgs); // two AutoResetEvents, one for send, one for receive if ( !AutoResetEvent.WaitAll(autoSendReceiveEvents , -1) ) Log("failed"); else Log("success"); // ... } private void OnSend( object sender , SocketAsyncEventArgs e ) { // ... Socket s = e.UserToken as Socket; byte[] receiveBuffer = new byte[ 4096 ]; e.SetBuffer(receiveBuffer , 0 , receiveBuffer.Length); e.Completed += new EventHandler<SocketAsyncEventArgs>(OnReceive); s.ReceiveAsync(e); // ... } private void OnReceive( object sender , SocketAsyncEventArgs e ) {} // ... if ( e.BytesTransferred > 0 ) { Int32 bytesTransferred = e.BytesTransferred; String received = Encoding.ASCII.GetString(e.Buffer , e.Offset , bytesTransferred); dataReceived += received; } autoSendReceiveEvents[ SendOperation ].Set(); // could be moved elsewhere autoSendReceiveEvents[ ReceiveOperation ].Set(); // releases mutexes } The code on the server is very similar except that it receives first and then sends a response - the server is not doing anything (that I can tell) to modify the connection after it sends a response. The problem is that the second time I hit SendReceive in the client, the connection is already in a weird state. Do I need to do something in the client to preserve the SocketAsyncEventArgs, and re-use the same object for the lifetime of the socket/connection? I'm not sure which eventargs object should hang around during the life of the connection or a given exchange. Do I need to do something, or Not do something in the server to ensure it continues to Receive data? The server setup and response processing looks like this: void Start() { // ... listenSocket.Bind(...); listenSocket.Listen(0); StartAccept(null); // note accept as soon as we start. OK? mutex.WaitOne(); } void StartAccept(SocketAsyncEventArgs acceptEventArg) { if ( acceptEventArg == null ) { acceptEventArg = new SocketAsyncEventArgs(); acceptEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(OnAcceptCompleted); } Boolean willRaiseEvent = this.listenSocket.AcceptAsync(acceptEventArg); if ( !willRaiseEvent ) ProcessAccept(acceptEventArg); // ... } private void OnAcceptCompleted( object sender , SocketAsyncEventArgs e ) { ProcessAccept(e); } private void ProcessAccept( SocketAsyncEventArgs e ) { // ... SocketAsyncEventArgs readEventArgs = new SocketAsyncEventArgs(); readEventArgs.SetBuffer(dataBuffer , 0 , Int16.MaxValue); readEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(OnIOCompleted); readEventArgs.UserToken = e.AcceptSocket; dataReceived = ""; // note server is degraded for single client/thread use // As soon as the client is connected, post a receive to the connection. Boolean willRaiseEvent = e.AcceptSocket.ReceiveAsync(readEventArgs); if ( !willRaiseEvent ) this.ProcessReceive(readEventArgs); // Accept the next connection request. this.StartAccept(e); } private void OnIOCompleted( object sender , SocketAsyncEventArgs e ) { // switch ( e.LastOperation ) case SocketAsyncOperation.Receive: ProcessReceive(e); // similar to client code // operate on dataReceived here case SocketAsyncOperation.Send: ProcessSend(e); // similar to client code } // execute this when a data has been processed into a response (ack, etc) private SendResponseToClient(string response) { // create buffer with response // currentEventArgs has class scope and is re-used currentEventArgs.SetBuffer(sendBuffer , 0 , sendBuffer.Length); Boolean willRaiseEvent = currentClient.SendAsync(currentEventArgs); if ( !willRaiseEvent ) ProcessSend(currentEventArgs); } A .NET trace shows the following when sending ABC\r\n: Socket#7588182::SendAsync() Socket#7588182::SendAsync(True#1) Data from Socket#7588182::FinishOperation(SendAsync) 00000000 : 41 42 43 0D 0A Socket#7588182::ReceiveAsync() Exiting Socket#7588182::ReceiveAsync() - True#1 And it stops there. It looks just like the first send from the client but the server shows no activity. I think that could be info overload for now but I'll be happy to provide more details as required. Thanks!

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  • problem processing xml in flex3

    - by john
    Hi All, First time here asking a question and still learning on how to format things better... so sorry about the format as it does not look too well. I have started learning flex and picked up a book and tried to follow the examples in it. However, I got stuck with a problem. I have a jsp page which returns xml which basically have a list of products. I am trying to parse this xml, in other words go through products, and create Objects for each product node and store them in an ArrayCollection. The problem I believe I am having is I am not using the right way of navigating through xml. The xml that is being returned from the server looks like this: <?xml version="1.0" encoding="ISO-8859-1"?><result type="success"> <products> <product> <id>6</id> <cat>electronics</cat> <name>Plasma Television</name> <desc>65 inch screen with 1080p</desc> <price>$3000.0</price> </product> <product> <id>7</id> <cat>electronics</cat> <name>Surround Sound Stereo</name> <desc>7.1 surround sound receiver with wireless speakers</desc> <price>$1000.0</price> </product> <product> <id>8</id> <cat>appliances</cat> <name>Refrigerator</name> <desc>Bottom drawer freezer with water and ice on the door</desc> <price>$1200.0</price> </product> <product> <id>9</id> <cat>appliances</cat> <name>Dishwasher</name> <desc>Large capacity with water saver setting</desc> <price>$500.0</price> </product> <product> <id>10</id> <cat>furniture</cat> <name>Leather Sectional</name> <desc>Plush leather with room for 6 people</desc> <price>$1500.0</price> </product> </products></result> And I have flex code that tries to iterate over products like following: private function productListHandler(e:JavaFlexStoreEvent):void { productData = new ArrayCollection(); trace(JavaServiceHandler(e.currentTarget).response); for each (var item:XML in JavaServiceHandler(e.currentTarget).response..product ) { productData.addItem( { id:item.id, item:item.name, price:item.price, description:item.desc }); } } with trace, I can see the xml being returned from the server. However, I cannot get inside the loop as if the xml was empty. In other words, JavaServiceHandler(e.currentTarget).response..product must be returning nothing. Can someone please help/point out what I could be doing wrong. My JavaServiceHandler class looks like this: package com.wiley.jfib.store.data { import com.wiley.jfib.store.events.JavaFlexStoreEvent; import flash.events.Event; import flash.events.EventDispatcher; import flash.net.URLLoader; import flash.net.URLRequest; public class JavaServiceHandler extends EventDispatcher { public var serviceURL:String = ""; public var response:XML; public function JavaServiceHandler() { } public function callServer():void { if(serviceURL == "") { throw new Error("serviceURL is a required parameter"); return; } var loader:URLLoader = new URLLoader(); loader.addEventListener(Event.COMPLETE, handleResponse); loader.load(new URLRequest(serviceURL)); // var httpService:HTTPService = new HTTPService(); // httpService.url = serviceURL; // httpService.resultFormat = "e4x"; // httpService.addEventListener(Event.COMPLETE, handleResponse); // httpService.send(); } private function handleResponse(e:Event):void { var loader:URLLoader = URLLoader(e.currentTarget); response = XML(loader.data); dispatchEvent(new JavaFlexStoreEvent(JavaFlexStoreEvent.DATA_LOADED) ); // var httpService:HTTPService = HTTPService(e.currentTarget); // response = httpService.lastResult.product; // dispatchEvent(new JavaFlexStoreEvent(JavaFlexStoreEvent.DATA_LOADED) ); } } } Even though I refer to this as mine and it is not in reality. This is from a Flex book as a code sample which does not work, go figure. Any help is appreciated. Thanks john

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  • Why can i read dirty rows in MySql

    - by acidzombie24
    I cant believe this, i always throught the below would be concurrency safe. I write to a row in one transaction and i am able to read the dirty value from another transaction/command/connection! Why is this possible (not my main question) isnt this not desired and cause more troubles!?! Anyways, i expected that once i write to a row nothing else will be able to read to the row until the transaction is finished. And at least if the row can be still read that the clean (original) value will be read. (but maybe that would cause problems as well if the transaction doesnt use the newly commited data from the other transaction when it is ran) I would like count to == 11. I thought this would be safe in all variants of sql. What can i do to either 1) Not read the dirty value but clean 2) Have that row be locked until the transaction is finished? static MySqlConnection MakeConn() { string connStr = "server=192.168.126.128;user=root;database=TestDB;port=3306;password=a;"; MySqlConnection conn = new MySqlConnection(connStr); conn.Open(); return conn; } static Semaphore sem1 = new Semaphore(1, 1); static Semaphore sem2 = new Semaphore(1, 1); static void Main2() { Console.WriteLine("Starting Test"); // sem1.WaitOne(); Console.WriteLine("1W"); sem2.WaitOne(); Console.WriteLine("2W"); Thread oThread = new Thread(new ThreadStart(fn2)); oThread.Start(); var conn = MakeConn(); var cmd = new MySqlCommand(@" CREATE TABLE IF NOT EXISTS Persons ( P_Id int NOT NULL, name varchar(255), count int, PRIMARY KEY (P_Id) )", conn); cmd.ExecuteNonQuery(); cmd.CommandText = "delete from Persons; insert into Persons(name, count) VALUES('E', '4');"; cmd.ExecuteNonQuery(); cmd.CommandText = "select count from Persons;"; var count = (int)cmd.ExecuteScalar(); Console.WriteLine("Finish inserting. v={0}", count); sem2.Release(); Console.WriteLine("2R"); sem1.WaitOne(); Console.WriteLine("1W"); Console.WriteLine("Starting transaction"); using (var tns = conn.BeginTransaction()) { cmd.CommandText = "update Persons set count=count+1"; cmd.ExecuteNonQuery(); cmd.CommandText = "select count from Persons;"; count = (int)cmd.ExecuteScalar(); Console.WriteLine("count is {0}", count); sem2.Release(); Console.WriteLine("2R"); sem1.WaitOne(); Console.WriteLine("1W"); count += 5; //10 cmd.CommandText = "update Persons set count=" + count.ToString(); cmd.ExecuteNonQuery(); cmd.CommandText = "select count from Persons;"; count = (int)cmd.ExecuteScalar(); Console.WriteLine("count is {0}", count); tns.Commit(); } Console.WriteLine("finished transaction 1"); sem2.Release(); Console.WriteLine("2R"); sem1.WaitOne(); Console.WriteLine("1W"); cmd.CommandText = "select count from Persons;"; count = (int)cmd.ExecuteScalar(); Console.WriteLine("count is {0}", count); sem2.Release(); Console.WriteLine("2R"); //sem1.WaitOne(); Console.WriteLine("1W"); } static void fn2() { int count; Console.WriteLine("Starting thread 2"); sem2.WaitOne(); Console.WriteLine("1W"); var conn = MakeConn(); var cmd = new MySqlCommand("", conn); sem1.Release(); Console.WriteLine("1R"); sem2.WaitOne(); Console.WriteLine("2W"); using (var tns = conn.BeginTransaction()) { cmd.CommandText = "update Persons set count=count+1"; cmd.ExecuteNonQuery(); cmd.CommandText = "select count from Persons;"; count = (int)cmd.ExecuteScalar(); Console.WriteLine("count is {0}", count); sem1.Release(); Console.WriteLine("1R"); sem2.WaitOne(); Console.WriteLine("2W"); tns.Commit(); } Console.WriteLine("finished transaction 2"); sem1.Release(); Console.WriteLine("1R"); sem2.WaitOne(); Console.WriteLine("2W"); cmd.CommandText = "select count from Persons;"; count = (int)cmd.ExecuteScalar(); Console.WriteLine("count is {0}", count); //should be 11. 4 + 1x2(one each thread) += 5 from first thread == 11 sem1.Release(); Console.WriteLine("1R"); } console Starting Test 1W 2W Starting thread 2 Finish inserting. v=4 2R 1W 1R 1W Starting transaction count is 5 2R 2W count is 6 1R 1W count is 10 finished transaction 1 2R 2W finished transaction 2 1R 1W count is 10 2R 2W count is 10 1R

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  • Animation issue caused by C# parameters passed by reference rather than value, but where?

    - by Jordan Roher
    I'm having trouble with sprite animation in XNA that appears to be caused by a struct passed as a reference value. But I'm not using the ref keyword anywhere. I am, admittedly, a C# noob, so there may be some shallow bonehead error in here, but I can't see it. I'm creating 10 ants or bees and animating them as they move across the screen. I have an array of animation structs, and each time I create an ant or bee, I send it the animation array value it requires (just [0] or [1] at this time). Deep inside the animation struct is a timer that is used to change frames. The ant/bee class stores the animation struct as a private variable. What I'm seeing is that each ant or bee uses the same animation struct, the one I thought I was passing in and copying by value. So during Update(), when I advance the animation timer for each ant/bee, the next ant/bee has its animation timer advanced by that small amount. If there's 1 ant on screen, it animates properly. 2 ants, it runs twice as fast, and so on. Obviously, not what I want. Here's an abridged version of the code. How is BerryPicking's ActorAnimationGroupData[] getting shared between the BerryCreatures? class BerryPicking { private ActorAnimationGroupData[] animations; private BerryCreature[] creatures; private Dictionary<string, Texture2D> creatureTextures; private const int maxCreatures = 5; public BerryPickingExample() { this.creatures = new BerryCreature[maxCreatures]; this.creatureTextures = new Dictionary<string, Texture2D>(); } public void LoadContent() { // Returns data from an XML file Reader reader = new Reader(); animations = reader.LoadAnimations(); CreateCreatures(); } // This is called from another function I'm not including because it's not relevant to the problem. // In it, I remove any creature that passes outside the viewport by setting its creatures[] spot to null. // Hence the if(creatures[i] == null) test is used to recreate "dead" creatures. Inelegant, I know. private void CreateCreatures() { for (int i = 0; i < creatures.Length; i++) { if (creatures[i] == null) { // In reality, the name selection is randomized creatures[i] = new BerryCreature("ant"); // Load content and texture (which I create elsewhere) creatures[i].LoadContent( FindAnimation(creatures[i].Name), creatureTextures[creatures[i].Name]); } } } private ActorAnimationGroupData FindAnimation(string animationName) { int yourAnimation = -1; for (int i = 0; i < animations.Length; i++) { if (animations[i].name == animationName) { yourAnimation = i; break; } } return animations[yourAnimation]; } public void Update(GameTime gameTime) { for (int i = 0; i < creatures.Length; i++) { creatures[i].Update(gameTime); } } } class Reader { public ActorAnimationGroupData[] LoadAnimations() { ActorAnimationGroupData[] animationGroup; XmlReader file = new XmlTextReader(filename); // Do loading... // Then later file.Close(); return animationGroup; } } class BerryCreature { private ActorAnimation animation; private string name; public BerryCreature(string name) { this.name = name; } public void LoadContent(ActorAnimationGroupData animationData, Texture2D sprite) { animation = new ActorAnimation(animationData); animation.LoadContent(sprite); } public void Update(GameTime gameTime) { animation.Update(gameTime); } } class ActorAnimation { private ActorAnimationGroupData animation; public ActorAnimation(ActorAnimationGroupData animation) { this.animation = animation; } public void LoadContent(Texture2D sprite) { this.sprite = sprite; } public void Update(GameTime gameTime) { animation.Update(gameTime); } } struct ActorAnimationGroupData { // There are lots of other members of this struct, but the timer is the only one I'm worried about. // TimerData is another struct private TimerData timer; public ActorAnimationGroupData() { timer = new TimerData(2); } public void Update(GameTime gameTime) { timer.Update(gameTime); } } struct TimerData { public float currentTime; public float maxTime; public TimerData(float maxTime) { this.currentTime = 0; this.maxTime = maxTime; } public void Update(GameTime gameTime) { currentTime += (float)gameTime.ElapsedGameTime.TotalSeconds; if (currentTime >= maxTime) { currentTime = maxTime; } } }

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  • Can this Query be corrected or different table structure needed? (database dumps provided)

    - by sandeepan
    This is a bit lengthy but I have provided sufficient details and kept things very clear. Please see if you can help. (I will surely accept answer if it solves my problem) I am sure a person experienced with this can surely help or suggest me to decide the tables structure. About the system:- There are tutors who create classes A tags based search approach is being followed Tag relations are created/edited when new tutors registers/edits profile data and when tutors create classes (this makes tutors and classes searcheable).For simplicity, let us consider only tutor name and class name are the fields which are matched against search keywords. In this example, I am considering - tutor "Sandeepan Nath" has created a class called "first class" tutor "Bob Cratchit" has created a class called "new class" Desired search results- AND logic to be appied on the search keywords and match against class and tutor data(class name + tutor name), in other words, All those classes be shown such that all the search terms are present in the class name or its tutor name. Example to be clear - Searching "first class" returns class with id_wc = 1. Working Searching "Sandeepan class" should also return class with id_wc = 1. Not working in System 2. Problem with profile editing and searching To tell in one sentence, I am facing a conflict between the ease of profile edition (edition of tag relations when tutor profiles are edited) and the ease of search logic. In the beginning, we had one table structure and search was easy but tag edition logic was very clumsy and unmaintainable(Check System 1 in the section below) . So we created separate tag relations tables to make profile edition simpler but search has become difficult. Please dump the tables so that you can run the search query I have given below and see the results. System 1 (previous system - search easy - profile edition difficult):- Only one table called All_Tag_Relations table had the all the tag relations. The tags table below is common to both systems 1 and 2. CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `all_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 1, 1, NULL), (2, 2, 1, NULL), (3, 1, 1, 1), (4, 2, 1, 1), (5, 3, 1, 1), (6, 4, 1, 1), (7, 6, 2, NULL), (8, 7, 2, NULL), (9, 6, 2, 2), (10, 7, 2, 2), (11, 5, 2, 2), (12, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); Please note that for every class, the tag rels of its tutor have to be duplicated. Example, for class with id_wc=1, the tag rel records with id_tag_rel = 3 and 4 are actually extras if you compare with the tag rel records with id_tag_rel = 1 and 2. System 2 (present system - profile edition easy, search difficult) Two separate tables Tutors_Tag_Relations and Webclasses_Tag_Relations have the corresponding tag relations data (Please dump into a separate database)- CREATE TABLE IF NOT EXISTS `tutors_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `tutors_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`) VALUES (1, 1, 1), (2, 2, 1), (3, 6, 2), (4, 7, 2); CREATE TABLE IF NOT EXISTS `webclasses_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `webclasses_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `webclasses_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 3, 1, 1), (2, 4, 1, 1), (3, 5, 2, 2), (4, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; insert into All_Tag_Relations select NULL,id_tag,id_tutor,NULL from Tutors_Tag_Relations; insert into All_Tag_Relations select NULL,id_tag,id_tutor,id_wc from Webclasses_Tag_Relations; Here you can see how easily tutor first name can be edited only in one place. But search has become really difficult, so on being advised to use a Temporary table, I am creating one at every search request, then dumping all the necessary data and then searching from it, I am creating this All_Tag_Relations table at search run time. Here I am just dumping all the data from the two tables Tutors_Tag_Relations and Webclasses_Tag_Relations. But, I am still not able to get classes if I search with tutor name This is the query which searches "first class". Running them on both the systems shows correct results (returns the class with id_wc = 1). SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =3 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 But, searching for "Sandeepan class" works only with the 1st system Here is the query which searches "Sandeepan class" SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =1)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =1 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 Can anybody alter this query and somehow do a proper join or something to get correct results. That solves my problem in a nice way. As you can figure out, the reason why it does not work in system 2 is that in system 1, for every class, one additional tag relation linking class and tutor name is present. e.g. for class first class, (records with id_tag_rel 3 and 4) which returns the class on searching with tutor name. So, you see the trade-off between the search and profile edition difficulty with the two systems. How do I overcome both. I have to reach a conclusion soon. So far my reasoning is it is definitely not good from a code maintainability point of view to follow the single tag rel table structure of system one, because in a real system while editing a field like "tutor qualifications", there can be as many records in tag rels table as there are words in qualification of a tutor (one word in a field = one tag relation). Now suppose a tutor has 100 classes. When he edits his qualification, all the tag rel rows corresponding to him are deleted and then as many copies are to be created (as per the new qualification data) as there are classes. This becomes particularly difficult if later more searcheable fields are added. The code cannot be robust. Is the best solution to follow system 2 (edition has to be in one table - no extra work for each and every class) and somehow re-create the all_tag_relations table like system 1 (from the tables tutor_tag_relations and webclasses_tag_relations), creating the extra tutor tag rels for each and every class by a tutor (which is currently missing in system 2's temporary all_tag_relations table). That would be a time consuming logic script. I doubt that table can be recreated without resorting to PHP sript (mysql alone cannot do that). But the problem is that running all this at search time will make search definitely slow. So, how do such systems work? How are such situations handled? I thought about we can run a cron which initiates that PHP script, say every 1 minute and replaces the existing all_tag_relations table as per new tag rels from tutor_tag_relations and webclasses_tag_relations (replaces means creates a new table, deletes the original and renames the new one as all_tag_relations, otherwise search won't work during that period- or is there any better way to that?). Anyway, the result would be that any changes by tutors will reflect in search in the next 1 minute and not immediately. An alternateve would be to initate that PHP script every time a tutor edits his profile. But here again, since many users may edit their profiles concurrently, will the creation of so many tables be a burden and can mysql make the server slow? Any help would be appreciated and working solution will be accepted as answer. Thanks, Sandeepan

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  • C# Memoization of functions with arbitrary number of arguments

    - by Lirik
    I'm trying to create a memoization interface for functions with arbitrary number of arguments, but I'm failing miserably. The first thing I tried is to define an interface for a function which gets memoized automatically upon execution: class EMAFunction:IFunction { Dictionary<List<object>, List<object>> map; class EMAComparer : IEqualityComparer<List<object>> { private int _multiplier = 97; public bool Equals(List<object> a, List<object> b) { List<object> aVals = (List<object>)a[0]; int aPeriod = (int)a[1]; List<object> bVals = (List<object>)b[0]; int bPeriod = (int)b[1]; return (aVals.Count == bVals.Count) && (aPeriod == bPeriod); } public int GetHashCode(List<object> obj) { // Don't compute hash code on null object. if (obj == null) { return 0; } // Get length. int length = obj.Count; List<object> vals = (List<object>) obj[0]; int period = (int) obj[1]; return (_multiplier * vals.GetHashCode() * period.GetHashCode()) + length;; } } public EMAFunction() { NumParams = 2; Name = "EMA"; map = new Dictionary<List<object>, List<object>>(new EMAComparer()); } #region IFunction Members public int NumParams { get; set; } public string Name { get; set; } public object Execute(List<object> parameters) { if (parameters.Count != NumParams) throw new ArgumentException("The num params doesn't match!"); if (!map.ContainsKey(parameters)) { //map.Add(parameters, List<double> values = new List<double>(); List<object> asObj = (List<object>)parameters[0]; foreach (object val in asObj) { values.Add((double)val); } int period = (int)parameters[1]; asObj.Clear(); List<double> ema = TechFunctions.ExponentialMovingAverage(values, period); foreach (double val in ema) { asObj.Add(val); } map.Add(parameters, asObj); } return map[parameters]; } public void ClearMap() { map.Clear(); } #endregion } Here are my tests of the function: private void MemoizeTest() { DataSet dataSet = DataLoader.LoadData(DataLoader.DataSource.FROM_WEB, 1024); List<String> labels = dataSet.DataLabels; Stopwatch sw = new Stopwatch(); IFunction emaFunc = new EMAFunction(); List<object> parameters = new List<object>(); int numRuns = 1000; long sumTicks = 0; parameters.Add(dataSet.GetValues("open")); parameters.Add(12); // First call for(int i = 0; i < numRuns; ++i) { emaFunc.ClearMap();// remove any memoization mappings sw.Start(); emaFunc.Execute(parameters); sw.Stop(); sumTicks += sw.ElapsedTicks; } Console.WriteLine("Average ticks not-memoized " + (sumTicks/numRuns)); sumTicks = 0; // Repeat call for (int i = 0; i < numRuns; ++i) { sw.Start(); emaFunc.Execute(parameters); sw.Stop(); sumTicks += sw.ElapsedTicks; } Console.WriteLine("Average ticks memoized " + (sumTicks/numRuns)); } The performance is confusing me... I expected the memoized function to be faster, but it didn't work out that way: Average ticks not-memoized 106,182 Average ticks memoized 198,854 I tried doubling the data instances to 2048, but the results were about the same: Average ticks not-memoized 232,579 Average ticks memoized 446,280 I did notice that it was correctly finding the parameters in the map and it going directly to the map, but the performance was still slow... I'm either open for troubleshooting help with this example, or if you have a better solution to the problem then please let me know what it is.

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  • Trouble with copying dictionaries and using deepcopy on an SQLAlchemy ORM object

    - by Az
    Hi there, I'm doing a Simulated Annealing algorithm to optimise a given allocation of students and projects. This is language-agnostic pseudocode from Wikipedia: s ? s0; e ? E(s) // Initial state, energy. sbest ? s; ebest ? e // Initial "best" solution k ? 0 // Energy evaluation count. while k < kmax and e > emax // While time left & not good enough: snew ? neighbour(s) // Pick some neighbour. enew ? E(snew) // Compute its energy. if enew < ebest then // Is this a new best? sbest ? snew; ebest ? enew // Save 'new neighbour' to 'best found'. if P(e, enew, temp(k/kmax)) > random() then // Should we move to it? s ? snew; e ? enew // Yes, change state. k ? k + 1 // One more evaluation done return sbest // Return the best solution found. The following is an adaptation of the technique. My supervisor said the idea is fine in theory. First I pick up some allocation (i.e. an entire dictionary of students and their allocated projects, including the ranks for the projects) from entire set of randomised allocations, copy it and pass it to my function. Let's call this allocation aOld (it is a dictionary). aOld has a weight related to it called wOld. The weighting is described below. The function does the following: Let this allocation, aOld be the best_node From all the students, pick a random number of students and stick in a list Strip (DEALLOCATE) them of their projects ++ reflect the changes for projects (allocated parameter is now False) and lecturers (free up slots if one or more of their projects are no longer allocated) Randomise that list Try assigning (REALLOCATE) everyone in that list projects again Calculate the weight (add up ranks, rank 1 = 1, rank 2 = 2... and no project rank = 101) For this new allocation aNew, if the weight wNew is smaller than the allocation weight wOld I picked up at the beginning, then this is the best_node (as defined by the Simulated Annealing algorithm above). Apply the algorithm to aNew and continue. If wOld < wNew, then apply the algorithm to aOld again and continue. The allocations/data-points are expressed as "nodes" such that a node = (weight, allocation_dict, projects_dict, lecturers_dict) Right now, I can only perform this algorithm once, but I'll need to try for a number N (denoted by kmax in the Wikipedia snippet) and make sure I always have with me, the previous node and the best_node. So that I don't modify my original dictionaries (which I might want to reset to), I've done a shallow copy of the dictionaries. From what I've read in the docs, it seems that it only copies the references and since my dictionaries contain objects, changing the copied dictionary ends up changing the objects anyway. So I tried to use copy.deepcopy().These dictionaries refer to objects that have been mapped with SQLA. Questions: I've been given some solutions to the problems faced but due to my über green-ness with using Python, they all sound rather cryptic to me. Deepcopy isn't playing nicely with SQLA. I've been told thatdeepcopy on ORM objects probably has issues that prevent it from working as you'd expect. Apparently I'd be better off "building copy constructors, i.e. def copy(self): return FooBar(....)." Can someone please explain what that means? I checked and found out that deepcopy has issues because SQLAlchemy places extra information on your objects, i.e. an _sa_instance_state attribute, that I wouldn't want in the copy but is necessary for the object to have. I've been told: "There are ways to manually blow away the old _sa_instance_state and put a new one on the object, but the most straightforward is to make a new object with __init__() and set up the attributes that are significant, instead of doing a full deep copy." What exactly does that mean? Do I create a new, unmapped class similar to the old, mapped one? An alternate solution is that I'd have to "implement __deepcopy__() on your objects and ensure that a new _sa_instance_state is set up, there are functions in sqlalchemy.orm.attributes which can help with that." Once again this is beyond me so could someone kindly explain what it means? A more general question: given the above information are there any suggestions on how I can maintain the information/state for the best_node (which must always persist through my while loop) and the previous_node, if my actual objects (referenced by the dictionaries, therefore the nodes) are changing due to the deallocation/reallocation taking place? That is, without using copy?

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  • Adding an overlay to Google maps with path taken

    - by user341652
    Hi, I am trying to write a class to track a person's location(s), and to draw the path they've taken on a MapView. This feature of the program is for the user to track their speed, distance, path, etc. while running/cycling (or whatever else) using their Android phone. This is my first Android application, and I am not sure how to do the Overlay object for the MapView. I also wanted to see if anyone had opinions on the GPS-Tracking part I have written (if it would work, if there is a better way of doing it, code examples would be helpful). I currently have this for my GPSTrackerService: package org.drexel.itrain.logic; import java.util.Vector; import org.drexel.itrain.Constants; import android.app.Notification; import android.app.NotificationManager; import android.app.Service; import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.location.GpsSatellite; import android.location.GpsStatus; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.location.GpsStatus.Listener; import android.os.Binder; import android.os.Bundle; import android.os.IBinder; import android.preference.PreferenceManager; public class GPSTrackingService extends Service { private static final int MAX_REASONABLE_SPEED = 60; private static final String TAG = "OGT.TrackingService"; private Context mContext; private LocationManager mLocationManager; private NotificationManager mNotificationManager; private Notification mNotification; private int mSatellites = 0; private int mTrackingState = Constants.GPS_TRACKING_UNKNOWN; private float mCurrentSpeed = 0; private float mTotalDistance = 0; private Location mPreviousLocation; private Vector<Location> mTrackedLocations; private LocationListener mLocationListener = null; private Listener mStatusListener = null; private IBinder binder = null; @Override public void onCreate() { super.onCreate(); this.mContext = getApplicationContext(); this.mLocationManager = (LocationManager) this.mContext.getSystemService( Context.LOCATION_SERVICE ); this.mNotificationManager = (NotificationManager) this.mContext.getSystemService( Context.NOTIFICATION_SERVICE ); this.mTrackedLocations = new Vector<Location>(); this.binder = new Binder(); SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this.mContext); binder = new Binder(); if(mTrackingState != Constants.GPS_TRACKING_UNKNOWN) { createListeners(); } } @Override public void onDestroy() { destroyListeneres(); } @Override public IBinder onBind(Intent intent) { return binder; } @Override public boolean onUnbind(Intent intent) { return true; } public boolean acceptLocation(Location proposedLocation) { if(!(proposedLocation.hasSpeed() || proposedLocation.hasAccuracy())) { return false; } else if(proposedLocation.getSpeed() >= MAX_REASONABLE_SPEED) { return false; } return true; } public void updateNotification() { //TODO Alert that no GPS sattelites are available (or are available) } public void startTracking() { this.mTrackingState = Constants.GPS_TRACKING_STARTED; this.mTotalDistance = 0; this.mCurrentSpeed = 0; this.mTrackedLocations = new Vector<Location>(); this.mPreviousLocation = null; createListeners(); } public void pauseTracking() { this.mTrackingState = Constants.GPS_TRACKING_PAUSED; this.mPreviousLocation = null; this.mCurrentSpeed = 0; } public void resumeTracking() { if(this.mTrackingState == Constants.GPS_TRACKING_STOPPED){ this.startTracking(); } this.mTrackingState = Constants.GPS_TRACKING_STARTED; } public void stopTracking() { this.mTrackingState = Constants.GPS_TRACKING_STOPPED; destroyListeneres(); } private void createListeners() { /** * LocationListener receives locations from */ this.mLocationListener = new LocationListener() { @Override public void onStatusChanged(String provider, int status, Bundle extras) { // TODO Auto-generated method stub } @Override public void onProviderEnabled(String provider) { // TODO Auto-generated method stub } @Override public void onProviderDisabled(String provider) { // TODO Auto-generated method stub } @Override public void onLocationChanged(Location location) { if(mTrackingState == Constants.GPS_TRACKING_STARTED && acceptLocation(location)) { if(mPreviousLocation != null) { //Add the distance between the new location and the previous location mTotalDistance += mPreviousLocation.distanceTo(location); } if(location.hasSpeed()) { mCurrentSpeed = location.getSpeed(); } else { mCurrentSpeed = -1; //-1 means speed N/A } mPreviousLocation = location; mTrackedLocations.add(location); } } }; /** * Receives updates reguarding the GPS Status */ this.mStatusListener = new GpsStatus.Listener() { @Override public synchronized void onGpsStatusChanged(int event) { switch( event ) { case GpsStatus.GPS_EVENT_SATELLITE_STATUS: { GpsStatus status = mLocationManager.getGpsStatus( null ); mSatellites = 0; Iterable<GpsSatellite> list = status.getSatellites(); for( GpsSatellite satellite : list ) { if( satellite.usedInFix() ) { mSatellites++; } } updateNotification(); break; } default: break; } } }; } /** * Destroys the LocationListenere and the GPSStatusListener */ private void destroyListeneres() { this.mLocationListener = null; this.mStatusListener = null; } /** * Gets the total distance traveled by the * * @return the total distance traveled (in meters) */ public float getDistance() { return mTotalDistance; } /** * Gets the current speed of the last good location * * @return the current speed (in meters/second) */ public float getSpeed() { return mCurrentSpeed; } } Any assistance would be much appreciated. This is my group's first Android app, and we are a little pressed for time at the moment. The project is for a class, and is available from SourceForge (currently called iTrain, soon to be renamed). Thanks in Advance, Steve

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  • How do you get XML::Pastor to set xsi:type for programmatically generated elements?

    - by Derrick
    I'm learning how to use Perl as an automation test framework tool for a Java web service and running into trouble generating xml requests from the Pastor generated modules. The problem is that when including a type that extends from the required type for an element, the xsi:type is not included in the generated xml string. Say, for example, I want to generate the following xml request from the modules that XML::Pastor generated from my xsd: <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <PromptAnswersRequest xmlns="http://mycompany.com/api"> <Uri>/some/url</Uri> <User ref="1"/> <PromptAnswers> <PromptAnswer xsi:type="textPromptAnswer" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <Prompt ref="2"/> <Children> <PromptAnswer xsi:type="choicePromptAnswer"> <Prompt ref="1"/> <Choice ref="2"/> </PromptAnswer> </Children> <Value>totally</Value> </PromptAnswer> </PromptAnswers> </PromptAnswersRequest> What I'm getting currently is this: <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <PromptAnswersRequest xmlns="http://mycompany.com/api"> <Uri>/some/url</Uri> <User ref="1"/> <PromptAnswers> <PromptAnswer> <Prompt ref="2"/> <Children> <PromptAnswer> <Prompt ref="1"/> <Choice ref="2"/> </PromptAnswer> </Children> <Value>totally</Value> </PromptAnswer> </PromptAnswers> </PromptAnswersRequest> Here are some relavent snippets from the xsd: <xs:complexType name="request"> <xs:sequence> <xs:element name="Uri" type="xs:anyURI"/> </xs:sequence> </xs:complexType> <xs:complexType name="promptAnswersRequest"> <xs:complexContent> <xs:extension base="api:request"> <xs:sequence> <xs:element name="User" type="api:ref"/> <xs:element name="PromptAnswers" type="api:promptAnswerList"/> </xs:sequence> </xs:extension> </xs:complexContent> </xs:complexType> <xs:complexType name="promptAnswerList"> <xs:sequence> <xs:element name="PromptAnswer" type="api:promptAnswer" minOccurs="0" maxOccurs="unbounded"/> </xs:sequence> </xs:complexType> <xs:complexType name="promptAnswer" abstract="true"> <xs:sequence> <xs:element name="Prompt" type="api:ref"/> <xs:element name="Children" type="api:promptAnswerList" minOccurs="0"/> </xs:sequence> </xs:complexType> <xs:complexType name="textPromptAnswer"> <xs:complexContent> <xs:extension base="promptAnswer"> <xs:sequence> <xs:element name="Value" type="api:nonEmptyString" minOccurs="0"/> </xs:sequence> </xs:extension> </xs:complexContent> </xs:complexType> And here are relavent parts of the script: my $promptAnswerList = new My::API::Type::promptAnswerList; my @promptAnswers; my $promptAnswerList2 = new My::API::Type::promptAnswerList; my @textPromptAnswerChildren; my $textPromptAnswer = new My::API::Type::textPromptAnswer; my $textPromptAnswerRef = new My::API::Type::ref; $textPromptAnswerRef->ref('2'); $textPromptAnswer->Prompt($textPromptAnswerRef); my $choicePromptAnswer = new My::API::Type::choicePromptAnswer; my $choicePromptAnswerPromptRef = new My::API::Type::ref; my $choicePromptAnswerChoiceRef = new My::API::Type::ref; $choicePromptAnswerPromptRef->ref('1'); $choicePromptAnswerChoiceRef->ref('2'); $choicePromptAnswer->Prompt($choicePromptAnswerPromptRef); $choicePromptAnswer->Choice($choicePromptAnswerChoiceRef); push(@textPromptAnswerChildren, $choicePromptAnswer); $promptAnswerList2->PromptAnswer(@textPromptAnswerChildren); $textPromptAnswer->Children($promptAnswerList2); $textPromptAnswer->Value('totally'); push(@promptAnswers, $pulseTextPromptAnswer); push(@promptAnswers, $textPromptAnswer); I haven't seen this addressed anywhere in the documentation for the XML::Pastor modules, so if anyone can point me at a good reference for its use it would be greatly appreciated. Also, I'm only using XML::Pastor because I don't know of any other modules that can do this, so if any of you know of something either easier to use, or more well maintained, please let me know about that too!

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  • How do implement a breadth first traversal?

    - by not looking for answer
    //This is what I have. I thought pre-order was the same and mixed it up with depth first! import java.util.LinkedList; import java.util.Queue; public class Exercise25_1 { public static void main(String[] args) { BinaryTree tree = new BinaryTree(new Integer[] {10, 5, 15, 12, 4, 8 }); System.out.print("\nInorder: "); tree.inorder(); System.out.print("\nPreorder: "); tree.preorder(); System.out.print("\nPostorder: "); tree.postorder(); //call the breadth method to test it System.out.print("\nBreadthFirst:"); tree.breadth(); } } class BinaryTree { private TreeNode root; /** Create a default binary tree */ public BinaryTree() { } /** Create a binary tree from an array of objects */ public BinaryTree(Object[] objects) { for (int i = 0; i < objects.length; i++) { insert(objects[i]); } } /** Search element o in this binary tree */ public boolean search(Object o) { return search(o, root); } public boolean search(Object o, TreeNode root) { if (root == null) { return false; } if (root.element.equals(o)) { return true; } else { return search(o, root.left) || search(o, root.right); } } /** Return the number of nodes in this binary tree */ public int size() { return size(root); } public int size(TreeNode root) { if (root == null) { return 0; } else { return 1 + size(root.left) + size(root.right); } } /** Return the depth of this binary tree. Depth is the * number of the nodes in the longest path of the tree */ public int depth() { return depth(root); } public int depth(TreeNode root) { if (root == null) { return 0; } else { return 1 + Math.max(depth(root.left), depth(root.right)); } } /** Insert element o into the binary tree * Return true if the element is inserted successfully */ public boolean insert(Object o) { if (root == null) { root = new TreeNode(o); // Create a new root } else { // Locate the parent node TreeNode parent = null; TreeNode current = root; while (current != null) { if (((Comparable)o).compareTo(current.element) < 0) { parent = current; current = current.left; } else if (((Comparable)o).compareTo(current.element) > 0) { parent = current; current = current.right; } else { return false; // Duplicate node not inserted } } // Create the new node and attach it to the parent node if (((Comparable)o).compareTo(parent.element) < 0) { parent.left = new TreeNode(o); } else { parent.right = new TreeNode(o); } } return true; // Element inserted } public void breadth() { breadth(root); } // Implement this method to produce a breadth first // search traversal public void breadth(TreeNode root){ if (root == null) return; System.out.print(root.element + " "); breadth(root.left); breadth(root.right); } /** Inorder traversal */ public void inorder() { inorder(root); } /** Inorder traversal from a subtree */ private void inorder(TreeNode root) { if (root == null) { return; } inorder(root.left); System.out.print(root.element + " "); inorder(root.right); } /** Postorder traversal */ public void postorder() { postorder(root); } /** Postorder traversal from a subtree */ private void postorder(TreeNode root) { if (root == null) { return; } postorder(root.left); postorder(root.right); System.out.print(root.element + " "); } /** Preorder traversal */ public void preorder() { preorder(root); } /** Preorder traversal from a subtree */ private void preorder(TreeNode root) { if (root == null) { return; } System.out.print(root.element + " "); preorder(root.left); preorder(root.right); } /** Inner class tree node */ private class TreeNode { Object element; TreeNode left; TreeNode right; public TreeNode(Object o) { element = o; } } }

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  • Getting parameter sent via html form and saving in my db

    - by Wesley
    I have error in my code i don't know to solve it please help me: My Servlet: package br.com.cad.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.Date; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import br.com.cad.dao.Cadastro; import br.com.cad.basica.Contato; public class AddDados extends HttpServlet{ protected void service(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { PrintWriter out = response.getWriter(); String nome = request.getParameter("nome"); String sobrenome = request.getParameter("sobrenome"); String rg = request.getParameter("rg"); String cpf = request.getParameter("cpf"); String sexo = request.getParameter("sexo"); StringBuilder finalDate = new StringBuilder("DataNascimento1") .append("/"+request.getParameter("DataNascimento??2")) .append("/"+request.getParameter("DataNascimento3")); try { SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy"); finalDate.toString(); } catch(ParseException e) { out.println("Erro de conversão da data"); return; } Contato contato = new Contato(); contato.setNome(nome); contato.setSobrenome(sobrenome); contato.setRg(rg); contato.setCpf(cpf); contato.setSexo(sexo); if ("Masculino".equals(contato.getSexo())) { contato.setSexo("M"); } else { contato.setSexo("F"); } contato.setDataNascimento1(dataNascimento1); //error here ????? contato.setDataNascimento2(dataNascimento2); //error here ????? contato.setDataNascimento3(dataNascimento3); //error here ????? Cadastro dao = new Cadastro(); dao.adiciona(contato); out.println("<html>"); out.println("<body>"); out.println("Contato " + contato.getNome() + " adicionado com sucesso"); out.println("</body>"); out.println("</html>"); } } My object dao package br.com.cad.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.SQLException; import java.sql.Date; import br.com.cad.dao.ConnectDb; import br.com.cad.basica.Contato; public class Cadastro { private Connection connection; public Cadastro() { this.connection = new ConnectDb().getConnection(); } public void adiciona(Contato contato) { String sql = "INSERT INTO dados_cadastro(pf_nome, pf_ultimonome, pf_rg, pf_cpf, pf_sexo,pf_dt_nasc) VALUES(?,?,?,?,?,?,?,?)"; try { PreparedStatement stmt = connection.prepareStatement(sql); stmt.setString(1, contato.getNome()); stmt.setString(2, contato.getSobrenome()); stmt.setString(3, contato.getRg()); stmt.setString(4, contato.getCpf()); stmt.setString(5, contato.getSexo()); stmt.setDate(6, new Date( contato.getDataNascimento1().getTimeInMillis()) ); // i think there are error here i don't know to solve it ????? stmt.execute(); stmt.close(); System.out.println("Cadastro realizado com sucesso!."); } catch(SQLException sqlException) { throw new RuntimeException(sqlException); } } } My class cadastro package br.com.cad.basica; import java.util.Calendar; public class Contato { private Long id; private String nome; private String sobrenome; private String email; private String endereco; private Calendar dataNascimento1; private Calendar dataNascimento2; private Calendar dataNascimento3; private String rg; private String cpf; private String sexo; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getNome() { return nome; } public void setNome(String nome) { this.nome = nome; } ...getters and setters I need to saving data in my mysql db, but i have some doubt about this code main how to get parameter send form html combobox( 1 for day, 2 for month, 3 for year of birth) i concatened with StringBuilder finalDate ... so i have some problem in my code please help me!!!

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  • How to match ColdFusion encryption with Java 1.4.2?

    - by JohnTheBarber
    * sweet - thanks to Edward Smith for the CF Technote that indicated the key from ColdFusion was Base64 encoded. See generateKey() for the 'fix' My task is to use Java 1.4.2 to match the results a given ColdFusion code sample for encryption. Known/given values: A 24-byte key A 16-byte salt (IVorSalt) Encoding is Hex Encryption algorithm is AES/CBC/PKCS5Padding A sample clear-text value The encrypted value of the sample clear-text after going through the ColdFusion code Assumptions: Number of iterations not specified in the ColdFusion code so I assume only one iteration 24-byte key so I assume 192-bit encryption Given/working ColdFusion encryption code sample: <cfset ThisSalt = "16byte-salt-here"> <cfset ThisAlgorithm = "AES/CBC/PKCS5Padding"> <cfset ThisKey = "a-24byte-key-string-here"> <cfset thisAdjustedNow = now()> <cfset ThisDateTimeVar = DateFormat( thisAdjustedNow , "yyyymmdd" )> <cfset ThisDateTimeVar = ThisDateTimeVar & TimeFormat( thisAdjustedNow , "HHmmss" )> <cfset ThisTAID = ThisDateTimeVar & "|" & someOtherData> <cfset ThisTAIDEnc = Encrypt( ThisTAID , ThisKey , ThisAlgorithm , "Hex" , ThisSalt)> My Java 1.4.2 encryption/decryption code swag: package so.example; import java.security.*; import javax.crypto.Cipher; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec; import org.apache.commons.codec.binary.*; public class SO_AES192 { private static final String _AES = "AES"; private static final String _AES_CBC_PKCS5Padding = "AES/CBC/PKCS5Padding"; private static final String KEY_VALUE = "a-24byte-key-string-here"; private static final String SALT_VALUE = "16byte-salt-here"; private static final int ITERATIONS = 1; private static IvParameterSpec ivParameterSpec; public static String encryptHex(String value) throws Exception { Key key = generateKey(); Cipher c = Cipher.getInstance(_AES_CBC_PKCS5Padding); ivParameterSpec = new IvParameterSpec(SALT_VALUE.getBytes()); c.init(Cipher.ENCRYPT_MODE, key, ivParameterSpec); String valueToEncrypt = null; String eValue = value; for (int i = 0; i < ITERATIONS; i++) { // valueToEncrypt = SALT_VALUE + eValue; // pre-pend salt - Length > sample length valueToEncrypt = eValue; // don't pre-pend salt Length = sample length byte[] encValue = c.doFinal(valueToEncrypt.getBytes()); eValue = Hex.encodeHexString(encValue); } return eValue; } public static String decryptHex(String value) throws Exception { Key key = generateKey(); Cipher c = Cipher.getInstance(_AES_CBC_PKCS5Padding); ivParameterSpec = new IvParameterSpec(SALT_VALUE.getBytes()); c.init(Cipher.DECRYPT_MODE, key, ivParameterSpec); String dValue = null; char[] valueToDecrypt = value.toCharArray(); for (int i = 0; i < ITERATIONS; i++) { byte[] decordedValue = Hex.decodeHex(valueToDecrypt); byte[] decValue = c.doFinal(decordedValue); // dValue = new String(decValue).substring(SALT_VALUE.length()); // when salt is pre-pended dValue = new String(decValue); // when salt is not pre-pended valueToDecrypt = dValue.toCharArray(); } return dValue; } private static Key generateKey() throws Exception { // Key key = new SecretKeySpec(KEY_VALUE.getBytes(), _AES); // this was wrong Key key = new SecretKeySpec(new BASE64Decoder().decodeBuffer(keyValueString), _AES); // had to un-Base64 the 'known' 24-byte key. return key; } } I cannot create a matching encrypted value nor decrypt a given encrypted value. My guess is it's something to do with how I'm handling the initial vector/salt. I'm not very crypto-savvy but I'm thinking I should be able to take the sample clear-text and produce the same encrypted value in Java as ColdFusion produced. I am able to encrypt/decrypt my own data with my Java code (so I'm consistent) but I cannot match nor decrypt the ColdFusion sample encrypted value. I have access to a local webservice that can test the encrypted output. The given ColdFusion output sample passes/decrypts fine (of course). If I try to decrypt the same sample with my Java code (using the actual key and salt) I get a "Given final block not properly padded" error. I get the same net result when I pass my attempt at encryption (using the actual key and salt) to the test webservice. Any Ideas?

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  • Dynamic object property populator (without reflection)

    - by grenade
    I want to populate an object's properties without using reflection in a manner similar to the DynamicBuilder on CodeProject. The CodeProject example is tailored for populating entities using a DataReader or DataRecord. I use this in several DALs to good effect. Now I want to modify it to use a dictionary or other data agnostic object so that I can use it in non DAL code --places I currently use reflection. I know almost nothing about OpCodes and IL. I just know that it works well and is faster than reflection. I have tried to modify the CodeProject example and because of my ignorance with IL, I have gotten stuck on two lines. One of them deals with dbnulls and I'm pretty sure I can just lose it, but I don't know if the lines preceding and following it are related and which of them will also need to go. The other, I think, is the one that pulled the value out of the datarecord before and now needs to pull it out of the dictionary. I think I can replace the "getValueMethod" with my "property.Value" but I'm not sure. I'm open to alternative/better ways of skinning this cat too. Here's the code so far (the commented out lines are the ones I'm stuck on): using System; using System.Collections.Generic; using System.Reflection; using System.Reflection.Emit; public class Populator<T> { private delegate T Load(Dictionary<string, object> properties); private Load _handler; private Populator() { } public T Build(Dictionary<string, object> properties) { return _handler(properties); } public static Populator<T> CreateBuilder(Dictionary<string, object> properties) { //private static readonly MethodInfo getValueMethod = typeof(IDataRecord).GetMethod("get_Item", new [] { typeof(int) }); //private static readonly MethodInfo isDBNullMethod = typeof(IDataRecord).GetMethod("IsDBNull", new [] { typeof(int) }); Populator<T> dynamicBuilder = new Populator<T>(); DynamicMethod method = new DynamicMethod("Create", typeof(T), new[] { typeof(Dictionary<string, object>) }, typeof(T), true); ILGenerator generator = method.GetILGenerator(); LocalBuilder result = generator.DeclareLocal(typeof(T)); generator.Emit(OpCodes.Newobj, typeof(T).GetConstructor(Type.EmptyTypes)); generator.Emit(OpCodes.Stloc, result); int i = 0; foreach (var property in properties) { PropertyInfo propertyInfo = typeof(T).GetProperty(property.Key, BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase | BindingFlags.FlattenHierarchy | BindingFlags.Default); Label endIfLabel = generator.DefineLabel(); if (propertyInfo != null && propertyInfo.GetSetMethod() != null) { generator.Emit(OpCodes.Ldarg_0); generator.Emit(OpCodes.Ldc_I4, i); //generator.Emit(OpCodes.Callvirt, isDBNullMethod); generator.Emit(OpCodes.Brtrue, endIfLabel); generator.Emit(OpCodes.Ldloc, result); generator.Emit(OpCodes.Ldarg_0); generator.Emit(OpCodes.Ldc_I4, i); //generator.Emit(OpCodes.Callvirt, getValueMethod); generator.Emit(OpCodes.Unbox_Any, property.Value.GetType()); generator.Emit(OpCodes.Callvirt, propertyInfo.GetSetMethod()); generator.MarkLabel(endIfLabel); } i++; } generator.Emit(OpCodes.Ldloc, result); generator.Emit(OpCodes.Ret); dynamicBuilder._handler = (Load)method.CreateDelegate(typeof(Load)); return dynamicBuilder; } } EDIT: Using Marc Gravell's PropertyDescriptor implementation (with HyperDescriptor) the code is simplified a hundred-fold. I now have the following test: using System; using System.Collections.Generic; using System.ComponentModel; using Hyper.ComponentModel; namespace Test { class Person { public int Id { get; set; } public string Name { get; set; } } class Program { static void Main() { HyperTypeDescriptionProvider.Add(typeof(Person)); var properties = new Dictionary<string, object> { { "Id", 10 }, { "Name", "Fred Flintstone" } }; Person person = new Person(); DynamicUpdate(person, properties); Console.WriteLine("Id: {0}; Name: {1}", person.Id, person.Name); Console.ReadKey(); } public static void DynamicUpdate<T>(T entity, Dictionary<string, object> properties) { foreach (PropertyDescriptor propertyDescriptor in TypeDescriptor.GetProperties(typeof(T))) if (properties.ContainsKey(propertyDescriptor.Name)) propertyDescriptor.SetValue(entity, properties[propertyDescriptor.Name]); } } } Any comments on performance considerations for both TypeDescriptor.GetProperties() & PropertyDescriptor.SetValue() are welcome...

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  • Can this Query can be corrected or different table structure needed? (question is clear, detailed, d

    - by sandeepan
    This is a bit lengthy but I have provided sufficient details and kept things very clear. Please see if you can help. (I will surely accept answer if it solves my problem) I am sure a person experienced with this can surely help or suggest me to decide the tables structure. About the system:- There are tutors who create classes A tags based search approach is being followed Tag relations are created/edited when new tutors registers/edits profile data and when tutors create classes (this makes tutors and classes searcheable).For simplicity, let us consider only tutor name and class name are the fields which are matched against search keywords. In this example, I am considering - tutor "Sandeepan Nath" has created a class called "first class" tutor "Bob Cratchit" has created a class called "new class" Desired search results- AND logic to be appied on the search keywords and match against class and tutor data(class name + tutor name), in other words, All those classes be shown such that all the search terms are present in the class name or its tutor name. Example to be clear - Searching "first class" returns class with id_wc = 1. Working Searching "Sandeepan class" should also return class with id_wc = 1. Not working in System 2. Problem with profile editing and searching To tell in one sentence, I am facing a conflict between the ease of profile edition (edition of tag relations when tutor profiles are edited) and the ease of search logic. In the beginning, we had one table structure and search was easy but tag edition logic was very clumsy and unmaintainable(Check System 1 in the section below) . So we created separate tag relations tables to make profile edition simpler but search has become difficult. Please dump the tables so that you can run the search query I have given below and see the results. System 1 (previous system - search easy - profile edition difficult):- Only one table called All_Tag_Relations table had the all the tag relations. The tags table below is common to both systems 1 and 2. CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `all_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 1, 1, NULL), (2, 2, 1, NULL), (3, 1, 1, 1), (4, 2, 1, 1), (5, 3, 1, 1), (6, 4, 1, 1), (7, 6, 2, NULL), (8, 7, 2, NULL), (9, 6, 2, 2), (10, 7, 2, 2), (11, 5, 2, 2), (12, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); Please note that for every class, the tag rels of its tutor have to be duplicated. Example, for class with id_wc=1, the tag rel records with id_tag_rel = 3 and 4 are actually extras if you compare with the tag rel records with id_tag_rel = 1 and 2. System 2 (present system - profile edition easy, search difficult) Two separate tables Tutors_Tag_Relations and Webclasses_Tag_Relations have the corresponding tag relations data (Please dump into a separate database)- CREATE TABLE IF NOT EXISTS `tutors_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `tutors_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`) VALUES (1, 1, 1), (2, 2, 1), (3, 6, 2), (4, 7, 2); CREATE TABLE IF NOT EXISTS `webclasses_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `webclasses_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `webclasses_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 3, 1, 1), (2, 4, 1, 1), (3, 5, 2, 2), (4, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; insert into All_Tag_Relations select NULL,id_tag,id_tutor,NULL from Tutors_Tag_Relations; insert into All_Tag_Relations select NULL,id_tag,id_tutor,id_wc from Webclasses_Tag_Relations; Here you can see how easily tutor first name can be edited only in one place. But search has become really difficult, so on being advised to use a Temporary table, I am creating one at every search request, then dumping all the necessary data and then searching from it, I am creating this All_Tag_Relations table at search run time. Here I am just dumping all the data from the two tables Tutors_Tag_Relations and Webclasses_Tag_Relations. But, I am still not able to get classes if I search with tutor name This is the query which searches "first class". Running them on both the systems shows correct results (returns the class with id_wc = 1). SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =3 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 But, searching for "Sandeepan class" works only with the 1st system Here is the query which searches "Sandeepan class" SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =1)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =1 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 Can anybody alter this query and somehow do a proper join or something to get correct results. That solves my problem in a nice way. As you can figure out, the reason why it does not work in system 2 is that in system 1, for every class, one additional tag relation linking class and tutor name is present. e.g. for class first class, (records with id_tag_rel 3 and 4) which returns the class on searching with tutor name. So, you see the trade-off between the search and profile edition difficulty with the two systems. How do I overcome both. I have to reach a conclusion soon. So far my reasoning is it is definitely not good from a code maintainability point of view to follow the single tag rel table structure of system one, because in a real system while editing a field like "tutor qualifications", there can be as many records in tag rels table as there are words in qualification of a tutor (one word in a field = one tag relation). Now suppose a tutor has 100 classes. When he edits his qualification, all the tag rel rows corresponding to him are deleted and then as many copies are to be created (as per the new qualification data) as there are classes. This becomes particularly difficult if later more searcheable fields are added. The code cannot be robust. Is the best solution to follow system 2 (edition has to be in one table - no extra work for each and every class) and somehow re-create the all_tag_relations table like system 1 (from the tables tutor_tag_relations and webclasses_tag_relations), creating the extra tutor tag rels for each and every class by a tutor (which is currently missing in system 2's temporary all_tag_relations table). That would be a time consuming logic script. I doubt that table can be recreated without resorting to PHP sript (mysql alone cannot do that). But the problem is that running all this at search time will make search definitely slow. So, how do such systems work? How are such situations handled? I thought about we can run a cron which initiates that PHP script, say every 1 minute and replaces the existing all_tag_relations table as per new tag rels from tutor_tag_relations and webclasses_tag_relations (replaces means creates a new table, deletes the original and renames the new one as all_tag_relations, otherwise search won't work during that period- or is there any better way to that?). Anyway, the result would be that any changes by tutors will reflect in search in the next 1 minute and not immediately. An alternateve would be to initate that PHP script every time a tutor edits his profile. But here again, since many users may edit their profiles concurrently, will the creation of so many tables be a burden and can mysql make the server slow? Any help would be appreciated and working solution will be accepted as answer. Thanks, Sandeepan

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