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  • Null Exception RelativeLayout

    - by theblixguy
    I am trying to remove objects from my relative layout and replace the background with another image but I get a java.lang.NullPointerException on this line: RelativeLayout ths = (RelativeLayout)findViewById(R.layout.activity_main); Below is my code: package com.ssrij.qrmag; import android.app.Activity; import android.content.Intent; import android.net.Uri; import android.os.Bundle; import android.view.View; import android.view.animation.Animation; import android.view.animation.TranslateAnimation; import android.view.animation.Animation.AnimationListener; import android.widget.Button; import android.widget.RelativeLayout; import android.widget.TextView; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // Initialize animations Animation a = new TranslateAnimation(1000,0,0,0); Animation a1 = new TranslateAnimation(1000,0,0,0); Animation a2 = new TranslateAnimation(1000,0,0,0); Animation a3 = new TranslateAnimation(1000,0,0,0); // Set animation durations (ms) a.setDuration(1200); a1.setDuration(1400); a2.setDuration(1600); a3.setDuration(1800); // Get a reference to the objects we want to apply the animation to final TextView v = (TextView)findViewById(R.id.textView1); final TextView v1 = (TextView)findViewById(R.id.textView2); final TextView v2 = (TextView)findViewById(R.id.TextView3); final Button v3 = (Button)findViewById(R.id.tap_scan); // Clear existing animations, just in case... v.clearAnimation(); v1.clearAnimation(); v2.clearAnimation(); v3.clearAnimation(); // Start animating v.startAnimation(a); v1.startAnimation(a1); v2.startAnimation(a2); v3.startAnimation(a3); a1.setAnimationListener(new AnimationListener() { @Override public void onAnimationStart(Animation animation) { // TODO Auto-generated method stub } @Override public void onAnimationRepeat(Animation animation) { // TODO Auto-generated method stub } @Override public void onAnimationEnd(Animation animation) { v.setVisibility(View.INVISIBLE); v1.setVisibility(View.INVISIBLE); v2.setVisibility(View.INVISIBLE); v3.setVisibility(View.INVISIBLE); RelativeLayout ths = (RelativeLayout)findViewById(R.layout.activity_main); ths.setBackgroundResource(R.drawable.blurbg); } }); } public void ScanQr(View v) { // Open the QR Scan page Intent a = new Intent(MainActivity.this, ScanActivity.class); startActivity(a); } } Is there anything that I am doing wrong?

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  • embedded Italic, bold fonts don't look the same in flex as in Windows...

    - by Mark
    ...unless they're something like "Times New Roman" or some other established font with a fully designed italic and bold, presumably in seperate files. Let me explain what I mean (though why no one has commented on this before I have no idea.) Numerous, numerous fonts do not have a seperate file for italic and bold, and in fact to the best of my knowledge don't even have italic and bold defined as such. But if you install them on windows (for example) and then use them in an app, You can still make use of italic and bold with those fonts. For italic, and oblique angle is just given to it, presumably by Windows, and it looks the same in all Windows apps, and the bold is just given a heavier weight. OK, well here's the problem: if you embed a font like that in a Flex app, as a "SystemFont" the italic and bold will not look the same as they do in Windows. Specifically, the oblique angle is invariably much less than in Windows (i.e the italic slant is much less) and the bold version is not bold enough. I vaguely recall thinking that there was some flex mechanism to assign custom oblique angles for italic (and weight for bold) but now can't recall what it is. Does anyone know the correct established way to do this. The following is actually a seperate (but related) font question (in case anyone is expert in all this.) Its rather a lengthy question and can be skipped, but its something that's plagued me for a long time. I mention above embedding as a "SystemFont", so iow something like this: package fonts { import flash.display.Sprite; public class FLW_Script_I extends Sprite { [Embed(systemFont='FLW Script', fontName='FLW Script', fontStyle='italic', fntWeight='normal', mimeType='application/x-font-truetype')] public var wrFont:Class; } } The other alternative to SystemFont for embedding, is "Source" followed by the name of an actual font file. If you try to embed one of the aformentioned single file fonts as a Source file (as opposed to SystemFont) and specify fontStyle='italic', then the mxmlc compiler will return an error and say there is no italic info in the font file. So up to now I have only been embedding these fonts as "SystemFont". The problem is, flex uses two different font compilers internally for Source embedding and SystemFont embedding. For source font embeds it uses the "Batik" compiler and for SystemFont, the JRE (Java Runtime) font compiler. Well actually the Batik is considered a superior compiler and generally produces better looking fonts. And also if you mix normal fonts compiled with Batik and italic compiled with JRE, sometimes the line spacing is different for the two, and it doesn't look right. So does anyone have an idea how to get mxmlc to do italic and bold for these single file fonts when embedding as "Source". Would there be a way using C++ or whatever to construct an "italic" font file from the SystemFont for such a font in windows.

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  • How to combine designable components with dependency injection

    - by Wim Coenen
    When creating a designable .NET component, you are required to provide a default constructor. From the IComponent documentation: To be a component, a class must implement the IComponent interface and provide a basic constructor that requires no parameters or a single parameter of type IContainer. This makes it impossible to do dependency injection via constructor arguments. (Extra constructors could be provided, but the designer would ignore them.) Some alternatives we're considering: Service Locator Don't use dependency injection, instead use the service locator pattern to acquire dependencies. This seems to be what IComponent.Site.GetService is for. I guess we could create a reusable ISite implementation (ConfigurableServiceLocator?) which can be configured with the necessary dependencies. But how does this work in a designer context? Dependency Injection via properties Inject dependencies via properties. Provide default instances if they are necessary to show the component in a designer. Document which properties need to be injected. Inject dependencies with an Initialize method This is much like injection via properties but it keeps the list of dependencies that need to be injected in one place. This way the list of required dependencies is documented implicitly, and the compiler will assists you with errors when the list changes. Any idea what the best practice is here? How do you do it? edit: I have removed "(e.g. a WinForms UserControl)" since I intended the question to be about components in general. Components are all about inversion of control (see section 8.3.1 of the UMLv2 specification) so I don't think that "you shouldn't inject any services" is a good answer. edit 2: It took some playing with WPF and the MVVM pattern to finally "get" Mark's answer. I see now that visual controls are indeed a special case. As for using non-visual components on designer surfaces, I think the .NET component model is fundamentally incompatible with dependency injection. It appears to be designed around the service locator pattern instead. Maybe this will start to change with the infrastructure that was added in .NET 4.0 in the System.ComponentModel.Composition namespace.

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  • Understanding SingleTableEntityPersister n QueryLoader

    - by Iapilgrim
    Hi, I have the Hibernate model @Cache(usage = CacheConcurrencyStrategy.NONE, region = SitesConstants.CACHE_REGION) public class Node extends StatefulEntity implements Inheritable, Cloneable { private Node _parent; private List<Node> _childNodes; .. } @Cache(usage = CacheConcurrencyStrategy.NONE, region = SitesConstants.CACHE_REGION) public class Page extends Node implements Defaultable, Securable { private RootZone _rootZone; ...... @OneToOne(fetch = FetchType.LAZY) @JoinColumn(name = "root_zone_id", insertable = false, updatable = false) public RootZone getRootZone() { return _rootZone; } public void setRootZone(RootZone rootZone) { if (rootZone != null) { rootZone.setPageId(this.getId()); _rootZone = rootZone; } } I want to get all pages ( call getSiteTree), so I using this query String hpql = "SELECT n FROM Node n "; See the trace I find Page.setRootZone(RootZone) line: 155 NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not available [native method] NativeMethodAccessorImpl.invoke(Object, Object[]) line: 39 DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 25 Method.invoke(Object, Object...) line: 597 BasicPropertyAccessor$BasicSetter.set(Object, Object, SessionFactoryImplementor) line: 66 PojoEntityTuplizer(AbstractEntityTuplizer).setPropertyValues(Object, Object[]) line: 352 PojoEntityTuplizer.setPropertyValues(Object, Object[]) line: 232 SingleTableEntityPersister(AbstractEntityPersister).setPropertyValues(Object, Object[], EntityMode) line: 3580 TwoPhaseLoad.initializeEntity(Object, boolean, SessionImplementor, PreLoadEvent, PostLoadEvent) line: 152 QueryLoader(Loader).initializeEntitiesAndCollections(List, Object, SessionImplementor, boolean) line: 877 QueryLoader(Loader).doQuery(SessionImplementor, QueryParameters, boolean) line: 752 QueryLoader(Loader).doQueryAndInitializeNonLazyCollections(SessionImplementor, QueryParameters, boolean) line: 259 QueryLoader(Loader).doList(SessionImplementor, QueryParameters) line: 2232 QueryLoader(Loader).listIgnoreQueryCache(SessionImplementor, QueryParameters) line: 2129 QueryLoader(Loader).list(SessionImplementor, QueryParameters, Set, Type[]) line: 2124 QueryLoader.list(SessionImplementor, QueryParameters) line: 401 QueryTranslatorImpl.list(SessionImplementor, QueryParameters) line: 363 HQLQueryPlan.performList(QueryParameters, SessionImplementor) line: 196 SessionImpl.list(String, QueryParameters) line: 1149 QueryImpl.list() line: 102 QueryImpl.getResultList() line: 67 NodeDaoImpl.getSiteTree(long) line: 358 PageNodeServiceImpl.getSiteTree(long) line: 797 NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not available [native method] NativeMethodAccessorImpl.invoke(Object, Object[]) line: 39 DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 25 Method.invoke(Object, Object...) line: 597 AopUtils.invokeJoinpointUsingReflection(Object, Method, Object[]) line: 307 JdkDynamicAopProxy.invoke(Object, Method, Object[]) line: 198 $Proxy100.getSiteTree(long) line: not available the calling setRootZone in Page makes Hibernate issue a hit to database. I don't want this. So my question is + Why query String hpql = "SELECT n FROM Node n "; issues un-expected trace logs like above. Why the query String hpql = "SELECT n.nodename FROM Node n " not? What is the mechanism behind? Note: Im using hibernate caching level 2. In case I don't want to see that trace logs. I mean I just get Node data only. How to do ? Thanks for your help. Sorry for my bad english :( Van

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  • Grouping geographical shapes

    - by grenade
    I am using Dundas Maps and attempting to draw a map of the world where countries are grouped into regions that are specific to a business implementation. I have shape data (points and segments) for each country in the world. I can combine countries into regions by adding all points and segments for countries within a region to a new region shape. foreach(var region in GetAllRegions()){ var regionShape = new Shape { Name = region.Name }; foreach(var country in GetCountriesInRegion(region.Id)){ var countryShape = GetCountryShape(country.Id); regionShape.AddSegments(countryShape.ShapeData.Points, countryShape.ShapeData.Segments); } map.Shapes.Add(regionShape); } The problem is that the country border lines still show up within a region and I want to remove them so that only regional borders show up. Dundas polygons must start and end at the same point. This is the case for all the country shapes. Now I need an algorithm that can: Determine where country borders intersect at a regional border, so that I can join the regional border segments. Determine which country borders are not regional borders so that I can discard them. Sort the resulting regional points so that they sequentialy describe the shape boundaries. Below is where I have gotten to so far with the map. You can see that the country borders still need to be removed. For example, the border between Mongolia and China should be discarded whereas the border between Mongolia and Russia should be retained. The reason I need to retain a regional border is that the region colors will be significant in conveying information but adjacent regions may be the same color. The regions can change to include or exclude countries and this is why the regional shaping must be dynamic. EDIT: I now know that I what I am looking for is a UNION of polygons. David Lean explains how to do it using the spatial functions in SQL Server 2008 which might be an option but my efforts have come to a halt because the resulting polygon union is so complex that SQL truncates it at 43,680 characters. I'm now trying to either find a workaround for that or find a way of doing the union in code.

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  • Writing Device Drivers for Microcontrollers, where to define IO Port pins?

    - by volting
    I always seem to encounter this dilemma when writing low level code for MCU's. I never know where to declare pin definitions so as to make the code as reusable as possible. In this case Im writing a driver to interface an 8051 to a MCP4922 12bit serial DAC. Im unsure how/where I should declare the pin definitions for The CS(chip select) and LDAC(data latch) for the DAC. At the moment there declared in the header file for the driver. Iv done a lot of research trying to figure out the best approach but havent really found anything. Im basically want to know what the best practices... if there are some books worth reading or online information, examples etc, any recommendations would be welcome. Just a snippet of the driver so you get the idea /** @brief This function is used to write a 16bit data word to DAC B -12 data bit plus 4 configuration bits @param dac_data A 12bit word @param ip_buf_unbuf_select Input Buffered/unbuffered select bit. Buffered = 1; Unbuffered = 0 @param gain_select Output Gain Selection bit. 1 = 1x (VOUT = VREF * D/4096). 0 =2x (VOUT = 2 * VREF * D/4096) */ void MCP4922_DAC_B_TX_word(unsigned short int dac_data, bit ip_buf_unbuf_select, bit gain_select) { unsigned char low_byte=0, high_byte=0; CS = 0; /**Select the chip*/ high_byte |= ((0x01 << 7) | (0x01 << 4)); /**Set bit to select DAC A and Set SHDN bit high for DAC A active operation*/ if(ip_buf_unbuf_select) high_byte |= (0x01 << 6); if(gain_select) high_byte |= (0x01 << 5); high_byte |= ((dac_data >> 8) & 0x0F); low_byte |= dac_data; SPI_master_byte(high_byte); SPI_master_byte(low_byte); CS = 1; LDAC = 0; /**Latch the Data*/ LDAC = 1; }

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  • git filter-branch chmod

    - by Evan Purkhiser
    I accidental had my umask set incorrectly for the past few months and somehow didn't notice. One of my git repositories has many files marked as executable that should be just 644. This repo has one main master branch, and about 4 private feature branches (that I keep rebased on top of the master). I've corrected the files in my master branch by running find -type f -exec chmod 644 {} \; and committing the changes. I then rebased my feature branches onto master. The problem is there are newly created files in the feature branches that are only in that branch, so they weren't corrected by my massive chmod commit. I didn't want to create a new commit for each feature branch that does the same thing as the commit I made on master. So I decided it would be best to go back through to each commit where a file was made and set the permissions. This is what I tried: git filter-branch -f --tree-filter 'chmod 644 `git show --diff-filter=ACR --pretty="format:" --name-only $GIT_COMMIT`; git add .' master.. It looked like this worked, but upon further inspection I noticed that the every commit after a commit containing a new file with the proper permissions of 644 would actually revert the change with something like: diff --git a b old mode 100644 new mode 100755 I can't for the life of me figure out why this is happening. I think I must be mis-understanding how git filter-branch works. My Solution I've managed to fix my problem using this command: git filter-branch -f --tree-filter 'FILES="$FILES "`git show --diff-filter=ACMR --pretty="format:" --name-only $GIT_COMMIT`; chmod 644 $FILES; true' development.. I keep adding onto the FILES variable to ensure that in each commit any file created at some point has the proper mode. However, I'm still not sure I really understand why git tracks the file mode for each commit. I had though that since I had fixed the mode of the file when it was first created that it would stay that mode unless one of my other commits explicit changed it to something else. That did not appear to the be the case. The reason I thought that this would work is from my understanding of rebase. If I go back to HEAD~5 and change a line of code, that change is propagated through, it doesn't just get changed back in HEAD~4.

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  • XSL transformation and special XML entities escaping

    - by Tomas R
    I have an XML file which is transformed with XSL. Some elements have to be changed, some have to be left as is - specifically, text with entities &quot;, &amp;, &apos;, &lt;, &gt; should be left as is, and in my case &quot; and &apos; are changed to " and ' accordingly. Test XML: <?xml version="1.0" encoding="UTF-8" ?> <root> <element> &quot; &amp; &apos; &lt; &gt; </element> </root> transformation file: <?xml version="1.0" encoding="UTF-8"?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"> <xsl:output method="xml" encoding="UTF-8" omit-xml-declaration="no" indent="no" /> <xsl:template match="element"> <xsl:copy> <xsl:value-of disable-output-escaping="no" select="." /> </xsl:copy> </xsl:template> </xsl:stylesheet> result: <?xml version="1.0" encoding="UTF-8"?> <element> " &amp; ' &lt; &gt; </element> desired result: <?xml version="1.0" encoding="UTF-8"?> <element> &quot; &amp; &apos; &lt; &gt; </element> I have 2 questions: why does some of those entities are transformed and other not? how can I get a desired result?

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  • EJB failure to update datamodel

    - by Ignacio
    Here my EJB @Entity @Table(name = "modelos") @NamedQueries({ @NamedQuery(name = "Modelos.findAll", query = "SELECT m FROM Modelos m"), @NamedQuery(name = "Modelos.findById", query = "SELECT m FROM Modelos m WHERE m.id = :id"), @NamedQuery(name = "Modelos.findByDescripcion", query = "SELECT m FROM Modelos m WHERE m.descripcion = :descripcion")}) public class Modelos implements Serializable { private static final long serialVersionUID = 1L; @Id @GeneratedValue(strategy = GenerationType.IDENTITY) @Basic(optional = false) @Column(name = "id") private Integer id; @Basic(optional = false) @Column(name = "descripcion") private String descripcion; @OneToMany(cascade = CascadeType.ALL, mappedBy = "idModelo") private Collection produtosCollection; @JoinColumn(name = "id_marca", referencedColumnName = "id") @ManyToOne(optional = false) private Marcas idMarca; public Modelos() { } public Modelos(Integer id) { this.id = id; } public Modelos(Integer id, String descripcion) { this.id = id; this.descripcion = descripcion; } public Modelos(Integer id, Marcas idMarca) { this.id = id; this.idMarca = idMarca; } public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getDescripcion() { return descripcion; } public void setDescripcion(String descripcion) { this.descripcion = descripcion; } public Collection<Produtos> getProdutosCollection() { return produtosCollection; } public void setProdutosCollection(Collection<Produtos> produtosCollection) { this.produtosCollection = produtosCollection; } public Marcas getIdMarca() { return idMarca; } public void setIdMarca(Marcas idMarca) { this.idMarca = idMarca; } @Override public int hashCode() { int hash = 0; hash += (id != null ? id.hashCode() : 0); return hash; } @Override public boolean equals(Object object) { // TODO: Warning - this method won't work in the case the id fields are not set if (!(object instanceof Modelos)) { return false; } Modelos other = (Modelos) object; if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) { return false; } return true; } @Override public String toString() { return "" + descripcion + ""; } } And the method accesing from the Modelosfacade public List findByMarcas(Marcas idMarca){ return em.createQuery("SELECT id, descripcion FROM Modelos WHERE idMarca = "+idMarca.getId()+"").getResultList(); } And the calling method from the controller public String createByMarcas() { //recreateModel(); items = new ListDataModel(ejbFacade.findByMarcas(current.getIdMarca())); updateCurrentItem(); System.out.println(current.getIdMarca()); return "List"; } I do not understand why I keep falling in an EJB exception.

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  • Problem on jboss lookup entitymanager

    - by Stefano
    I have my ear-project deployed in jboss 5.1GA. From webapp i don't have problem, the lookup of my ejb3 work fine! es: ShoppingCart sc= (ShoppingCart) (new InitialContext()).lookup("idelivery-ear-1.0/ShoppingCartBean/remote"); also the iniection of my EntityManager work fine! @PersistenceContext private EntityManager manager; From test enviroment (I use Eclipse) the lookup of the same ejb3 work fine! but the lookup of entitymanager or PersistenceContext don't work!!! my good test case: public void testClient() { Properties properties = new Properties(); properties.put("java.naming.factory.initial","org.jnp.interfaces.NamingContextFactory"); properties.put("java.naming.factory.url.pkgs","org.jboss.naming:org.jnp.interfaces"); properties.put("java.naming.provider.url","localhost"); Context context; try{ context = new InitialContext(properties); ShoppingCart cart = (ShoppingCart) context.lookup("idelivery-ear-1.0/ShoppingCartBean/remote"); // WORK FINE } catch (Exception e) { e.printStackTrace(); } } my bad test : EntityManagerFactory emf = Persistence.createEntityManagerFactory("idelivery"); EntityManager em = emf.createEntityManager(); //test1 EntityManager em6 = (EntityManager) new InitialContext().lookup("java:comp/env/persistence/idelivery"); //test2 PersistenceContext em3 = (PersistenceContext)(new InitialContext()).lookup("idelivery/remote"); //test3 my persistence.xml <persistence-unit name="idelivery" transaction-type="JTA"> <jta-data-source>java:ideliveryDS</jta-data-source> <properties> <property name="hibernate.hbm2ddl.auto" value="create-drop" /><!--validate | update | create | create-drop--> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect" /> <property name="hibernate.show_sql" value="true" /> <property name="hibernate.format_sql" value="true" /> </properties> </persistence-unit> my datasource: <datasources> <local-tx-datasource> <jndi-name>ideliveryDS</jndi-name> ... </local-tx-datasource> </datasources> I need EntityManager and PersistenceContext to test my query before build ejb... Where is my mistake?

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  • Workflow for statistical analysis and report writing

    - by ws
    Does anyone have any wisdom on workflows for data analysis related to custom report writing? The use-case is basically this: Client commissions a report that uses data analysis, e.g. a population estimate and related maps for a water district. The analyst downloads some data, munges the data and saves the result (e.g. adding a column for population per unit, or subsetting the data based on district boundaries). The analyst analyzes the data created in (2), gets close to her goal, but sees that needs more data and so goes back to (1). Rinse repeat until the tables and graphics meet QA/QC and satisfy the client. Write report incorporating tables and graphics. Next year, the happy client comes back and wants an update. This should be as simple as updating the upstream data by a new download (e.g. get the building permits from the last year), and pressing a "RECALCULATE" button, unless specifications change. At the moment, I just start a directory and ad-hoc it the best I can. I would like a more systematic approach, so I am hoping someone has figured this out... I use a mix of spreadsheets, SQL, ARCGIS, R, and Unix tools. Thanks! PS: Below is a basic Makefile that checks for dependencies on various intermediate datasets (w/ ".RData" suffix) and scripts (".R" suffix). Make uses timestamps to check dependencies, so if you 'touch ss07por.csv', it will see that this file is newer than all the files / targets that depend on it, and execute the given scripts in order to update them accordingly. This is still a work in progress, including a step for putting into SQL database, and a step for a templating language like sweave. Note that Make relies on tabs in its syntax, so read the manual before cutting and pasting. Enjoy and give feedback! http://www.gnu.org/software/make/manual/html%5Fnode/index.html#Top R=/home/wsprague/R-2.9.2/bin/R persondata.RData : ImportData.R ../../DATA/ss07por.csv Functions.R $R --slave -f ImportData.R persondata.Munged.RData : MungeData.R persondata.RData Functions.R $R --slave -f MungeData.R report.txt: TabulateAndGraph.R persondata.Munged.RData Functions.R $R --slave -f TabulateAndGraph.R report.txt

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  • Comparing Nested object properties using C#

    - by Kumar
    I have a method which compares two objects and returns a list of all the property names which are different. public static IList<string> GetDifferingProperties(object source, object) { var sourceType = source.GetType(); var sourceProperties = sourceType.GetProperties(); var targetType = target.GetType(); var targetProperties = targetType.GetProperties(); var properties = (from s in sourceProperties from t in targetProperties where s.Name == t.Name && s.PropertyType == t.PropertyType && s.GetValue(source,null) != t.GetValue(target,null) select s.Name).ToList(); return properties; } For example if I have two classes as follows: public class Address { public string AddressLine1 { get; set; } public string AddressLine2 { get; set; } public string City { get; set; } public string State { get; set; } public string Zip { get; set; } } public class Employee { public string FirstName { get; set; } public string MiddleName { get; set; } public string LastName { get; set; } public Address EmployeeAddress { get; set; } } I am trying to compare the following two employee instances: var emp1Address = new Address(); emp1Address.AddressLine1 = "Microsoft Corporation"; emp1Address.AddressLine2 = "One Microsoft Way"; emp1Address.City = "Redmond"; emp1Address.State = "WA"; emp1Address.Zip = "98052-6399"; var emp1 = new Employee(); emp1.FirstName = "Bill"; emp1.LastName = "Gates"; emp1.EmployeeAddress = emp1Address; var emp2Address = new Address(); emp2Address.AddressLine1 = "Gates Foundation"; emp2Address.AddressLine2 = "One Microsoft Way"; emp2Address.City = "Redmond"; emp2Address.State = "WA"; emp2Address.Zip = "98052-6399"; var emp2 = new Employee(); emp2.FirstName = "Melinda"; emp2.LastName = "Gates"; emp2.EmployeeAddress = emp2Address; So when I pass these two employee objects to my GetDifferingProperties method currently it returns FirstName and EmployeeAddress, but it does not tell me which exact property (which in this case is Address1) in the EmployeeAddress has changed. How can I tweak this method to get something like EmployeeAddress.Address1?

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  • Retrieving/Updating Entity Framework POCO objects that already exist in the ObjectContext

    - by jslatts
    I have a project using Entity Framework 4.0 with POCOs (data is stored in SQL DB, lazyloading is enabled) as follows: public class ParentObject { public int ID {get; set;} public virtual List<ChildObject> children {get; set;} } public class ChildObject { public int ID {get; set;} public int ChildRoleID {get; set;} public int ParentID {get; set;} public virtual ParentObject Parent {get; set;} public virtual ChildRoleObject ChildRole {get; set;} } public class ChildRoleObject { public int ID {get; set;} public string Name {get; set;} public virtual List<ChildObject> children {get; set;} } I want to create a new ChildObject, assign it a role, then add it to an existing ParentObject. Afterwards, I want to send the new ChildObject to the caller. The code below works fine until it tries to get the object back from the database. The newChildObjectInstance only has the ChildRoleID set and does not contain a reference to the actual ChildRole object. I try and pull the new instance back out of the database in order to populate the ChildRole property. Unfortunately, in this case, instead of creating a new instance of ChildObject and assigning it to retreivedChildObject, EF finds the existing ChildObject in the context and returns the in-memory instance, with a null ChildRole property. public ChildObject CreateNewChild(int id, int roleID) { SomeObjectContext myRepository = new SomeObjectContext(); ParentObject parentObjectInstance = myRepository.GetParentObject(id); ChildObject newChildObjectInstance = new ChildObject() { ParentObject = parentObjectInstance, ParentID = parentObjectInstance.ID, ChildRoleID = roleID }; parentObjectInstance.children.Add(newChildObjectInstance); myRepository.Save(); ChildObject retreivedChildObject = myRepository.GetChildObject(newChildObjectInstance.ID); string assignedRoleName = retreivedChildObject.ChildRole.Name; //Throws exception, ChildRole is null return retreivedChildObject; } I have tried setting MergeOptions to Overwrite, calling ObjectContext.Refresh() and ObjectContext.DetectChanges() to no avail... I suspect this is related to the proxy objects that EF injects when working with POCOs. Has anyone run into this issue before? If so, what was the solution?

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  • string categorization strategies

    - by Andrew Heath
    I'm the one-man dev team on a fledgling military history website. One aspect of the site is a catalog of ~1,200 individual battles, including the nations & formations (regiments, divisions, etc) which took part. The formation information (as well as the other battle info) was manually imported from a series of books by a 10-man volunteer team. The formations were listed in groups with varying formatting and abbreviation patterns. At the time I set up the data collection forms I couldn't think of a good way to process that data... and elected to store it all as strings in the MySQL database and sort it out later. Well, "later" - as it tends to happen - has arrived. :-) Each battle has 2+ records in the database - one for each nation that participated. Each record has a formations text string listing the formations present as the volunteer chose to add them. Some real examples: 39th Grenadier Rgmt, 26th Volksgrenadier Division 2nd Luftwaffe Field Division, 246th Infantry Division 247th Rifle Division, 255th Tank Brigade 2nd Luftwaffe Field Division, SS Cavalry Division 28th Tank Brigade, 158th Rifle Division, 135th Rifle Division, 81st Tank Brigade, 242nd Tank Brigade 78th Infantry Division 3rd Kure Special Naval Landing Force, Tulagi Seaplane Base personnel 1st Battalion 505th Infantry Regiment The ultimate goal is for each individual force to have an ID, so that its participation can be traced throughout the battle database. Formation hierarchy, such as the final item above 1st Battalion (of the) 505th Infantry Regiment also needs to be preserved. In that case, 1st Battalion and 505th Infantry Regiment would be split, but 1st Battalion would be flagged as belonging to the 505th. In database terms, I think I want to pull the formation field out of the current battle info table and create three new tables: FORMATION [id] [name] FORMATION_HIERARCHY [id] [parent] [child] FORMATION_BATTLE [f_id] [battle_id] It's simple to explain, but complicated to enact. What I'm looking for from the SO community is just some tips on how best to tackle this problem. Ideally there's some sort of method to solving this that I'm not aware of. However, as a last resort, I could always code a classification framework and call my volunteers back to sort through 2,500+ records...

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  • How to apply or chain multiple matching templates in XSLT?

    - by Ignatius
    I am working on a stylesheet employing many templates with match attributes: <xsl:template match="//one" priority="0.7"> <xsl:param name="input" select="."/> <xsl:value-of select="util:uppercase($input)"/> <xsl:next-match /> </xsl:template> <xsl:template match="/stuff/one"> <xsl:param name="input" select="."/> <xsl:value-of select="util:add-period($input)"/> </xsl:template> <xsl:function name="util:uppercase"> <xsl:param name="input"/> <xsl:value-of select="upper-case($input)"/> </xsl:function> <xsl:function name="util:add-period"> <xsl:param name="input"/> <xsl:value-of select="concat($input,'.')"/> </xsl:function> What I would like to do is be able to 'chain' the two functions above, so that an input of 'string' would be rendered in the output as 'STRING.' (with the period.) I would like to do this in such a way that doesn't require knowledge of other templates in any other template. So, for instance, I would like to be able to add a "util:add-colon" method without having to open up the hood and monkey with the existing templates. I was playing around with the <xsl:next-match/> instruction to accomplish this. Adding it to the first template above does of course invoke both util:uppercase and util:add-period, but the output is an aggregation of each template output (i.e. 'STRINGstring.') It seems like there should be an elegant way to chain any number of templates together using something like <xsl:next-match/>, but have the output of each template feed the input of the next one in the chain. Am I overlooking something obvious?

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  • Recursion with an Array; can't get the right value to return

    - by Matt
    Recursive Solution: Not working! Explanation: An integer, time, is passed into the function. It's then used to provide an end to the FOR statement (counter<time). The IF section (time == 0) provides a base case where the recursion should terminate, returning 0. The ELSE section is where the recursive call occurs: total is a private variable defined in the header file, elsewhere. It's initialized to 0 in a constructor, elsewhere. The function calls itself, recursively, adding productsAndSales[time-1][0] to total, again, and again, until the base call. Then the total is returned, and printed out later. Well, that's what I hoped for anyway. What I imagined would happen is that I would add up all the values in this one column of the array and the value would get returned, and printed out. Instead if returns 0. If I set the IF section to "return 1", I noticed that it returns powers of 2, for whatever value time is. EG: Time = 3, it returns 2*2 + 1. If time = 5, it returns 2*2*2*2 + 1. I don't understand why it's not returning the value I'm expecting. int CompanySales::calcTotals( int time ) { cout << setw( 4 ); if ( time == 0 ) { return 0; } else { return total += calcTotals( productsAndSales[ time-1 ][ 0 ]); } } Iterative Solution: Working! Explanation: An integer, time, is passed into the function. It's then used to provide an end to the FOR statement (counter<time). The FOR statement cycles through an array, adding all of the values in one column together. The value is then returned (and elsewhere in the program, printed out). Works perfectly. int CompanySales::calcTotals( int time ) { int total = 0; cout << setw( 4 ); for ( int counter = 0; counter < time; counter++ ) { total += productsAndSales[counter][0]; } return total0; }

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  • Is there anyway to exclude artifacts inherited from a parent POM?

    - by Miguel
    Artifacts from dependencies can be excluded by declaring an <exclusions> element inside a <dependency> But in this case it's needed to exclude an artifact inherited from a parent project. An excerpt of the POM under discussion follows: <project> <modelVersion>4.0.0</modelVersion> <groupId>test</groupId> <artifactId>jruby</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <artifactId>base</artifactId> <groupId>es.uniovi.innova</groupId> <version>1.0.0</version> </parent> <dependencies> <dependency> <groupId>com.liferay.portal</groupId> <artifactId>ALL-DEPS</artifactId> <version>1.0</version> <scope>provided</scope> <type>pom</type> </dependency> </dependencies> </project> base artifact, depends on javax.mail:mail-1.4.jar, and ALL-DEPS depends on another version of the same library. Due to the fact that mail.jar from ALL-DEPS exist on the execution environment, although not exported, collides with the mail.jar that exists on the parent, which is scoped as compile. A solution could be to rid off mail.jar from the parent POM, but most of the projects that inherit base, need it (as is a transtive dependency for log4j). So What I would like to do is to simply exclude parent's library from the child project, as it could be done if base was a dependency and not the parent pom: ... <dependency> <artifactId>base</artifactId> <groupId>es.uniovi.innova</groupId> <version>1.0.0</version> <type>pom<type> <exclusions> <exclusion> <groupId>javax.mail</groupId> <artifactId>mail</artifactId> </exclusion> </exclusions> </dependency> ...

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  • NSLinguisticTagger on the contents of an NSTextStorage- crashing bug

    - by Remy Porter
    I'm trying to use an NSLinguisticTagger to monitor the contents of an NSTextStorage and provide some contextual information based on what the user types. To that end, I have an OverlayManager object, which wires up this relationship: -(void) setView:(NSTextView*) view { _view = view; _layout = view.layoutManager; _storage = view.layoutManager.textStorage; //get the TextStorage from the view [_tagger setString:_storage.string]; //pull the string out, this grabs the mutable version [self registerForNotificationsOn:self->_storage]; //subscribe to the willProcessEditing notification } When an edit occurs, I make sure to trap it and notify the tagger (and yes, I know I'm being annoyingly inconsistent with member access, I'm rusty on Obj-C, I'll fix it later): - (void) textStorageWillProcessEditing:(NSNotification*) notification{ if ([self->_storage editedMask] & NSTextStorageEditedCharacters) { NSRange editedRange = [self->_storage editedRange]; NSUInteger delta = [self->_storage changeInLength]; [_tagger stringEditedInRange:editedRange changeInLength:delta]; //should notify the tagger of the changes [self highlightEdits:self]; } } The highlightEdits message delegates the job out to a pool of "Overlay" objects. Each contains a block of code similar to this: [tagger enumerateTagsInRange:range scheme:NSLinguisticTagSchemeLexicalClass options:0 usingBlock:^(NSString *tag, NSRange tokenRange, NSRange sentenceRange, BOOL *stop) { if (tag == PartOfSpeech) { [self applyHighlightToRange:tokenRange onStorage:storage]; } }]; And that's where the problem is- the enumerateTagsInRange method crashes out with a message: 2014-06-04 10:07:19.692 WritersEditor[40191:303] NSMutableRLEArray replaceObjectsInRange:withObject:length:: Out of bounds This problem doesn't occur if I don't link to the mutable copy of the underlying string and instead do a [[_storage string] copy], but obviously I don't want to copy the entire backing store every time I want to do tagging. This all should be happening in the main run loop, so I don't think this is a threading issue. The NSRange I'm enumerating tags on exists both in the NSTextStorage and in the NSLinguisticTagger's view of the string. It's not even the fact that the applyHighlightToRange call adds attributes to the string, because it crashes before even reaching that line. I attempted to build a test case around the problem, but can't replicate it in those situations: - (void) testEdit { NSAttributedString* str = [[NSMutableAttributedString alloc] initWithString:@"Quickly, this is a test."]; text = [[NSTextStorage alloc] initWithAttributedString:str]; NSArray* schemes = [NSLinguisticTagger availableTagSchemesForLanguage:@"en"]; tagger = [[NSLinguisticTagger alloc] initWithTagSchemes:schemes options:0]; [tagger setString:[text string]]; [text beginEditing]; [[text mutableString] appendString:@"T"]; NSRange edited = [text editedRange]; NSUInteger length = [text changeInLength]; [text endEditing]; [tagger stringEditedInRange:edited changeInLength:length]; [tagger enumerateTagsInRange:edited scheme:NSLinguisticTagSchemeLexicalClass options:0 usingBlock:^(NSString *tag, NSRange tokenRange, NSRange sentenceRange, BOOL *stop) { //doesn't matter, this should crash }]; } That code doesn't crash.

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  • ASP.NET- forcing child/container events to fire before parent onload?

    - by Hans Gruber
    I'm working on a questionnaire type application in which questions are stored in a database. Therefore, I create my controls dynamically on every Page.OnLoad. This works like a charm and ViewState is persisted between postbacks because I ensure that my dynamic controls always have the same generated Control.ID. In addition to the user control that dynamically populates the questions, my questionnaire page also contains a 'Status' section (also encapsulated by a user control) which represents the status of the questionnaire (choices are 'Complete', 'Started' or 'In Progress'). If the user changes the status of questionnaire (i.e. from 'In Progress' to 'Complete'), I need to postback to the server because the contents of the dynamic portion of the questionnaire depend on the selected status. Some questions are always present regardless of status, and yet others may not be present at all for the selected status. The point is, when the status changes, I have to postback to the page and render the right set of questions. Additionally, I need to preserve any user entered values for those questions which are 'always available'. However, due to the page life cycle in ASP.NET, the 'Status' user control's OnLoad, which contains the correct status needed to load the right questions from the DB, doesn't get executed until after the 'dynamic questions' user control has already been populated (with the wrong/stale values). To get around this, I raise an event from my 'Status' user control to the main page to indicate that the Status has changed. The main page then raises an event on the 'dynamic questions' user control. Since by the time this event bubbles up, the 'dynamic questions' user control has already loaded the 'wrong' questions from the DB, it first calls Controls.Clear. It then happily uses the new status to query the database for the 'correct' questions and does a Control.Add() on each. FYI, Control.IDs are consistent across postbacks. This solution works...sorta. The correct set of questions for the selected status do get rendered; however ViewState is getting lost for those 'always available' questions. I'm guessing this is because the 'dynamic questions' user control calls Controls.Clear when responding to the status changed event. This must somehow kill the association between ViewState and my dynamic controls, even though the Control.ID are consistent. This seems like such a common requirement, I'm virtually certain there is a better, cleaner and less error prone approach to accomplish this. In case its not plain obvious, I haven't been able to grok the ASP.NET page life-cycle despite working with it for the last year. Any help is much appreciated!

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  • Failed to obtain JDBC Driver for MySQL under Tomcat environment

    - by Michael Mao
    Hi all: I've been trying to obtain the Driver class for JDBC connection to MySQL. The workstation is running on Linux, Fedora 10. I have manually set up the classpath variable for Java by CLI like this: bash-3.2$ echo $CLASSPATH /home/cmao/public_html/jsp/mysql-connector-java-5.1.12-bin.jar This shows that I've added the lastest mysql connection jar archive to my CLASSPATH variable. I've created a test JSP page which can be found here And source code for this page is: <%@page language="java"%> <%@page import="java.sql.*"%> <%@page import="java.util.*"%> <html> <head> <title>UTS JDBC MySQL connection test page</title> </head> <body> <% Connection con = null; out.print("Java version is : " + System.getProperty("java.version") + "<br />"); out.print("Tomcat version is : " + application.getServerInfo() + "<br />"); out.print("Servlet version is: " + application.getMajorVersion() + "<br />"); out.print("JSP version is : " + JspFactory.getDefaultFactory().getEngineInfo().getSpecificationVersion() +"<br />"); //out.print("Java classpath is : " + System.getProperty("java.class.path")+ "<br />"); //out.print("JSP classpath is : " + appliaction.getAttribute("org.apache.catalina.jsp_classpath") + "<br />"); //out.print("Tomcat classpath is : " + System.getProperty("org.apache.tomcat.common.classpath") + "<br />"); try { Class c = Class.forName("com.mysql.jdbc.Driver"); } catch(Exception e) { out.println("Error! Failed to obtain JDBC driver for MySQL... Missing class \"com.mysql.jdbc.Driver\"<br />"); } %> </body> </html> None of those commented out line would work, various Jsper Expetions would be thrown. You can check those Error pages from the following links: classpath Error page catalina Error page tomcat Error page It seems, from my limited knowledge of JSP and Servlet, the Tomcat environment "ignores" my Java CLASSPATH? In which case I cannot configure the MySQL JDBC package to let my Servlets(a JSP is but a Servlet anyway) work. I am not sure how to fix this issue. would it be better if I use an IDE like Eclipse or NetBeans and create a real Java "web app" so that everything can be "self-configured" by the usage of a web.config XML configuration file? So that I can certainly bypass this Tomcat environment restriction? Many thanks for the suggestions in advance.

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  • Killing Mysql prcoesses staying in sleep command.

    - by Shino88
    Hey I am connecting a MYSQL database through hibernate and i seem to have processes that are not being killed after they are finished in the session. I have called flush and close on each session but when i check the server the last processes are still there with a sleep command. This is a new problem which i am having and was not the case yesterday. Is there any way i can ensure the killng of theses processes when i am done with a session. Below is an example of one of my classes. public JSONObject check() { //creates a new session needed to add elements to a database Session session = null; //holds the result of the check in the database JSONObject check = new JSONObject(); try{ //creates a new session needed to add elements to a database SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory(); session = sessionFactory.openSession(); if (justusername){ //query created to select a username from user table String hquery = "Select username from User user Where username = ? "; //query created Query query = session.createQuery(hquery); //sets the username of the query the values JSONObject contents query.setString(0, username); // executes query and adds username string variable String user = (String) query.uniqueResult(); //checks to see if result is found (null if not found) if (user == null) { //adds false to Jobject if not found check.put("indatabase", "false"); } else { check.put("indatabase", "true"); } //adds check to Jobject to say just to check username check.put("justusername", true); } else { //query created to select a username and password from user table String hquery = "Select username from User user Where username = :user and password = :pass "; Query query = session.createQuery(hquery); query.setString("user", username); query.setString("pass", password); String user = (String) query.uniqueResult(); if(user ==null) { check.put("indatabase", false); } else { check.put("indatabase", true); } check.put("justusername", false); } }catch(Exception e){ System.out.println(e.getMessage()); //logg.log(Level.WARNING, " Exception", e.getMessage()); }finally{ // Actual contact insertion will happen at this step session.flush(); session.close(); } //returns Jobject return check; }

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  • dynamiclly schedule a lead sales agent

    - by Josh
    I have a website that I'm trying to migrate from classic asp to asp.net. It had a lead schedule, where each sales agent would be featured for the current day, or part of the day.The next day a new agent would be scheduled. It was driven off a database table that had a row for each day in it. So to figure out if a sales agent would show on a day, it was easy, just find today's date in the table. Problem was it ran out rows, and you had to run a script to update the lead days 6 months at a time. Plus if there was ever any change to the schedule, you had to delete all the rows and re-run the script. So I'm trying to code it where sql server figures that out for me, and no script has to be ran. I have a table like so CREATE TABLE [dbo].[LeadSchedule]( [leadid] [int] IDENTITY(1,1) NOT NULL, [userid] [int] NOT NULL, [sunday] [bit] NOT NULL, [monday] [bit] NOT NULL, [tuesday] [bit] NOT NULL, [wednesday] [bit] NOT NULL, [thursday] [bit] NOT NULL, [friday] [bit] NOT NULL, [saturday] [bit] NOT NULL, [StartDate] [smalldatetime] NULL, [EndDate] [smalldatetime] NULL, [StartTime] [time](0) NULL, [EndTime] [time](0) NULL, [order] [int] NULL, So the user can schedule a sales agent depending on their work schedule. Also if they wanted to they could split certain days, or sales agents by time, So from Midnight to 4 it was one agent, from 4-midnight it was another. So far I've tried using a numbers table, row numbers, goofy date math, and I'm at a loss. Any suggestions on how to handle this purely from sql code? If it helps, the table should always be small, like less than 20 never over 100. update After a few hours all I've managed to come up with is the below. It doesn't handle filling in days not available or times, just rotates through all the sales agents with leadTable as ( select leadid,userid,[order],StartDate, case DATEPART(dw,getdate()) when 1 then sunday when 2 then monday when 3 then tuesday when 4 then wednesday when 5 then thursday when 6 then friday when 7 then saturday end as DayAvailable , ROW_NUMBER() OVER (ORDER BY [order] ASC) AS ROWID from LeadSchedule where GETDATE()>=StartDate and (CONVERT(time(0),GETDATE())>= StartTime or StartTime is null) and (CONVERT(time(0),GETDATE())<= EndTime or EndTime is null) ) select userid, DATEADD(d,(number+ROWID-2)*totalUsers,startdate ) leadday from (select *, (select COUNT(1) from leadTable) totalUsers from leadTable inner join Numbers on 1=1 where DayAvailable =1 ) tb1 order by leadday asc

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  • Using a function with reference as a function with pointers?

    - by epatel
    Today I stumbled over a piece of code that looked horrifying to me. The pieces was chattered in different files, I have tried write the gist of it in a simple test case below. The code base is routinely scanned with FlexeLint on a daily basis, but this construct has been laying in the code since 2004. The thing is that a function implemented with a parameter passing using references is called as a function with a parameter passing using pointers...due to a function cast. The construct has worked since 2004 on Irix and now when porting it actually do work on Linux/gcc too. My question now. Is this a construct one can trust? I can understand if compiler constructors implement the reference passing as it was a pointer, but is it reliable? Are there hidden risks? Should I change the fref(..) to use pointers and risk braking anything in the process? What to you think? #include <iostream> using namespace std; // ---------------------------------------- // This will be passed as a reference in fref(..) struct string_struct { char str[256]; }; // ---------------------------------------- // Using pointer here! void fptr(const char *str) { cout << "fptr: " << str << endl; } // ---------------------------------------- // Using reference here! void fref(string_struct &str) { cout << "fref: " << str.str << endl; } // ---------------------------------------- // Cast to f(const char*) and call with pointer void ftest(void (*fin)()) { void (*fcall)(const char*) = (void(*)(const char*))fin; fcall("Hello!"); } // ---------------------------------------- // Let's go for a test int main() { ftest((void (*)())fptr); // test with fptr that's using pointer ftest((void (*)())fref); // test with fref that's using reference return 0; }

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  • Java: omitting a data member from the equals method.

    - by cchampion
    public class GamePiece { public GamePiece(char cLetter, int nPointValue) { m_cLetter=cLetter; m_nPointValue=nPointValue; m_nTurnPlaced=0; //has not been placed on game board yet. } public char GetLetter() {return m_cLetter;} public int GetPointValue() {return m_nPointValue;} public int GetTurnPlaced() {return m_nTurnPlaced;} public void SetTurnPlaced(int nTurnPlaced) { m_nTurnPlaced=nTurnPlaced; } @Override public boolean equals(Object obj) { /*NOTE to keep this shorter I omitted some of the null checking and instanceof stuff. */ GamePiece other = (GamePiece) obj; //not case sensitive, and I don`t think we want it to be here. if(m_cLetter != other.m_cLetter) { return false; } if(m_nPointValue != other.m_nPointValue) { return false; } /* NOTICE! m_nPointValue purposely omitted. It does not affect hashcode or equals */ return true; } @Override public int hashCode() { /* NOTICE! m_nPointValue purposely omitted. It should not affect hashcode or equals */ final int prime = 41; return prime * (prime + m_nPointValue + m_cLetter); } private char m_cLetter; private int m_nPointValue; private int m_nTurnPlaced;//turn which the game piece was placed on the game board. Does not affect equals or has code! } Consider the given piece of code. This object has been immutable until the introduction of the m_nTurnPlaced member (which can be modified by the SetTurnPlaced method, so now GamePiece becomes mutable). GamePiece is used in an ArrayList, I call contains and remove methods which both rely on the equals method to be implemented. My question is this, is it ok or common practice in Java for some members to not affect equals and hashcode? How will this affect its use in my ArrayList? What type of java Collections would it NOT be safe to use this object now that it is mutable? I've been told that you're not supposed to override equals on mutable objects because it causes some collections to behave "strangely" (I read that somewhere in the java documentation).

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  • Hibernate Communications Link Failure in Hibernate Based Java Servlet application powered by MySQL

    - by Vatsala
    Let me describe my question - I have a Java application - Hibernate as the DB interfacing layer over MySQL. I get the communications link failure error in my application. The occurence of this error is a very specific case. I get this error , When I leave mysql server unattended for more than approximately 6 hours (i.e. when there are no queries issued to MySQL for more than approximately 6 hours). I am pasting a top 'exception' level description below, and adding a pastebin link for a detailed stacktrace description. javax.persistence.PersistenceException: org.hibernate.exception.JDBCConnectionException: Cannot open connection - Caused by: org.hibernate.exception.JDBCConnectionException: Cannot open connection - Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure - The last packet successfully received from the server was 1,274,868,181,212 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago. - Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure - The last packet successfully received from the server was 1,274,868,181,212 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago. - Caused by: java.net.ConnectException: Connection refused: connect the link to the pastebin for further investigation - http://pastebin.com/4KujAmgD What I understand from these exception statements is that MySQL is refusing to take in any connections after a period of idle/nil activity. I have been reading up a bit about this via google search, and came to know that one of the possible ways to overcome this is to set values for c3p0 properties as c3p0 comes bundled with Hibernate. Specifically, I read from here http://www.mchange.com/projects/c3p0/index.html that setting two properties idleConnectionTestPeriod and preferredTestQuery will solve this for me. But these values dont seem to have had an effect. Is this the correct approach to fixing this? If not, what is the right way to get over this? The following are related Communications Link Failure questions at stackoverflow.com, but I've not found a satisfactory answer in their answers. http://stackoverflow.com/questions/2121829/java-db-communications-link-failure http://stackoverflow.com/questions/298988/how-to-handle-communication-link-failure Note 1 - i dont get this error when I am using my application continuosly. Note 2 - I use JPA with Hibernate and hence my hibernate.dialect,etc hibernate properties reside within the persistence.xml in the META-INF folder (does that prevent the c3p0 properties from working?) edit - Here are the c3p0 parameters I tried out - select 1; 2

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