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  • Correct use of setEmtpyView in AdapterView

    - by Sebi
    I'm really having trouble using the setEmptyView method. I tried it to implement it in GridView and ListView, but both of them didnt work. Here a sample codeblock: networkGames = (GridView) baseLayer.findViewById(R.id.all_game_grid_network); networkGames.setBackgroundResource(R.drawable.game_border); networkGames.setSelector(R.drawable.game_active_border); networkGames.setOnItemClickListener(new NetworkGameListener()); networkGames.setEmptyView(View.inflate(baseLayer, R.drawable.no_network_games, null)); networkGames.setAdapter(new NetworkAdapter()); The network adapter contains no items: private class NetworkAdapter extends BaseAdapter { /* (non-Javadoc) * @see android.widget.Adapter#getCount() */ @Override public int getCount() { return 0; } /* (non-Javadoc) * @see android.widget.Adapter#getItem(int) */ @Override public Object getItem(int position) { return null; } /* (non-Javadoc) * @see android.widget.Adapter#getItemId(int) */ @Override public long getItemId(int position) { return 0; } /* (non-Javadoc) * @see android.widget.Adapter#getView(int, android.view.View, android.view.ViewGroup) */ @Override public View getView(int position, View convertView, ViewGroup parent) { return null; } } I also tried to call networkGames.setAdapter(null), but this doesnt work either. My emtpyView looks like this: <LinearLayout android:id="@+id/LinearLayout01" android:layout_width="fill_parent" android:layout_height="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android"> <TextView android:text="There are currently no network games available. Start a new one." android:id="@+id/TextView01" android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center"> </TextView> </LinearLayout> I really don't know what I'm doing wrong. I also read various tutorials, but none of them metnioned any problems.

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  • Removing PDF attachments via itext

    - by r00fus
    I'm trying to remove attachments from a number of my pdf files (I can extract via pdftk, so preserving them is not an issue). I coded the following based on an example found from a google search: import java.io.FileOutputStream; import java.io.IOException; import com.lowagie.text.*; import com.lowagie.text.pdf.*; class pdfremoveattachment { public static void main(String[] args) throws IOException, DocumentException { if (args.length < 2) { System.out.println("Usage: java PDFremoveAttachments source.pdf target.pdf"); System.exit(1); } PdfReader sourcePDF = new PdfReader(args[0]); removeAttachments(sourcePDF); FileOutputStream targetFOS = new FileOutputStream(args[1]); PdfStamper targetPDF = new PdfStamper(sourcePDF,targetFOS); targetPDF.close(); } public static void removeAttachments(PdfReader reader) { PdfDictionary catalog = reader.getCatalog(); // System.out.println(catalog.getAsDict(PdfName.NAME)); // this would print "null" PdfDictionary names = (PdfDictionary)PdfReader.getPdfObject(catalog.get(PdfName.NAMES)); // System.out.println(names.toString()); //this returns NPE if( names != null) { PdfDictionary files = (PdfDictionary) PdfReader.getPdfObject(names.get(PdfName.FILEATTACHMENT)); if( files!= null ){ for( Object key : files.getKeys() ){ files.remove((PdfName)key); } files = (PdfDictionary) PdfReader.getPdfObject(names.get(PdfName.EMBEDDEDFILES)); } if( files!= null ){ for( Object key : files.getKeys() ){ files.remove((PdfName)key); } reader.removeUnusedObjects(); } } } } If anyone knows how I might be able to remove attachments, I'd greatly appreciate a reply.

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  • sending a selected value from a dropdownlist to a servlet with xhr

    - by kawtousse
    I am trying to send the clicked value of a dropdown list to my servlet to run a SQL query using the value received. To do it I am using Ajax like that: function showProject(prj) { xmlhttp = GetXmlHttpObject(); if (xmlhttp == null) { alert ("Browser does not support HTTP Request"); return; } var url = "ServletxmlGenerator.java"; idprj = prj.options[prj.selectedIndex].value; url = url + "?idprj=" + idprj; xmlhttp.onreadystatechange = stateChanged; xmlhttp.open("GET",url,true); xmlhttp.send(null); } The servlet when String projectcode=(String) request.getParameter("idprj"); returns null. When I select a value from the JSP that construct the dropdown list and from which the function showProject is handled the same thing is happned. It returns always null. So the parameter(idprj) is not passed anyway. How can I handle with this. I need to send the selected value to the servlet to run my SQL query.

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  • Refining data stored in SQLite - how to join several contacts?

    - by Krab
    Problem background Imagine this problem. You have a water molecule which is in contact with other molecules (if the contact is a hydrogen bond, there can be 4 other molecules around my water). Like in the following picture (A, B, C, D are some other atoms and dots mean the contact). A B . . O / \ H H . . C D I have the information about all the dots and I need to eliminate the water in the center and create records describing contacts of A-C, A-D, A-B, B-C, B-D, and C-D. Database structure Currently, I have the following structure in the database: Table atoms: "id" integer PRIMARY KEY, "amino" char(3) NOT NULL, (HOH for water or other value) other columns identifying the atom Table contacts: "acceptor_id" integer NOT NULL, (the atom near to my hydrogen, here C or D) "donor_id" integer NOT NULL, (here A or B) "directness" char(1) NOT NULL, (this should be D for direct and W for water-mediated) other columns about the contact, such as the distance Current solution (insufficient) Now, I'm going through all the contacts which have donor.amino = "HOH". In this sample case, this would select contacts from C and D. For each of these selected contacts, I look up contacts having the same acceptor_id as is the donor_id in the currently selected contact. From this information, I create the new contact. At the end, I delete all contacts to or from HOH. This way, I am obviously unable to create C-D and A-B contacts (the other 4 are OK). If I try a similar approach - trying to find two contacts having the same donor_id, I end up with duplicate contacts (C-D and D-C). Is there a simple way to retrieve all six contacts without duplicates? I'm dreaming about some one page long SQL query which retrievs just these six wanted rows. :-) It is preferable to conserve information about who is donor where possible, but not strictly necessary. Big thanks to all of you who read this question to this point.

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  • Masspay and MySql

    - by Mike
    Hi, I am testing Paypal's masspay using their 'MassPay NVP example' and I having difficulty trying to amend the code so inputs data from my MySql database. Basically I have user table in MySql which contains email address, status of payment (paid,unpaid) and balance. CREATE TABLE `users` ( `user_id` int(10) unsigned NOT NULL auto_increment, `email` varchar(100) collate latin1_general_ci NOT NULL, `status` enum('unpaid','paid') collate latin1_general_ci NOT NULL default 'unpaid', `balance` int(10) NOT NULL default '0', PRIMARY KEY (`user_id`) ) ENGINE=MyISAM AUTO_INCREMENT=6 DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci Data : 1 [email protected] paid 100 2 [email protected] unpaid 11 3 [email protected] unpaid 20 4 [email protected] unpaid 1 5 [email protected] unpaid 20 6 [email protected] unpaid 15 I then have created a query which selects users with an unpaid balance of $10 and above : $conn = db_connect(); $query=$conn->query("SELECT * from users WHERE balance >='10' AND status = ('unpaid')"); What I would like to is for each record returned from the query for it to populate the code below: Now the code which I believe I need to amend is as follows: for($i = 0; $i < 3; $i++) { $receiverData = array( 'receiverEmail' => "[email protected]", 'amount' => "example_amount",); $receiversArray[$i] = $receiverData; } However I just can't get it to work, I have tried using mysqli_fetch_array and then replaced "[email protected]" with $row['email'] and "example_amount" with row['balance'] in various methods of coding but it doesn't work. Also I need it to loop to however many rows that were retrieved from the query as <3 in the for loop above. So the end result I am looking for is for the $nvpStr string to pass with something like this: $nvpStr = "&EMAILSUBJECT=test&RECEIVERTYPE=EmailAddress&CURRENCYCODE=USD&[email protected]&L_Amt=11&[email protected]&L_Amt=11&[email protected]&L_Amt=20&[email protected]&L_Amt=20&[email protected]&L_Amt=15"; Thanks

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  • Implementing Java Priority Queue

    - by Kay
    public class PriorityQueue<T> { private PriorityNode<T> head, tail; private int numItems; public PriorityQueue(){ numItems = 0; head=null; tail=null; } public void add(int priority, T value){ PriorityNode<T> newNode = new PriorityNode<T>(priority,value); if(numItems == 0){ head = newNode; tail = newNode; } else{ head.setNext(newNode); head = newNode; } } } Where PriorityNode is defined as: public class PriorityNode<T> implements Comparable<T> { private T value; private PriorityNode<T> next; private int priority; public PriorityNode(int priority,T newValue){ value = newValue; next = null; priority = 0; } public PriorityNode(T newValue){ value = newValue; next = null; priority = 0; } public void setPriority(int priority){ this.priority = priority; } public int getPriority(){ return this.priority; } public T getValue(){ return value; } public PriorityNode<T> getNext(){ return next; } public void setNext(PriorityNode<T> nextNode){ this.next = nextNode; } public void setValue(T newValue){ value = newValue; } public int compareTo(int pri) { // TODO Auto-generated method stub if(this.priority<pri){ return -1; } else if(this.priority == pri){ return 0; } else{ return 1; } } } I'm having a lot of difficulty using the Comparator here and implementing a priority queue - please point me in the right direction.

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  • MySQL: Request to select the last 10 send/received messages to/by different users

    - by Yako malin
    I want to select the 10 last messages you received OR you sent TO different users. For example the results must be shown like that: 1. John1 - last message received 04/17/10 3:12 2. Thomy - last message sent 04/16/10 1:26 3. Pamela - last message received 04/12/10 3:51 4. Freddy - last message received 03/28/10 9:00 5. Jack - last message sent 03/20/10 4:53 6. Tom - last message received 02/01/10 7:41 ..... Table looks like: CREATE TABLE `messages` ( `id` int(11) NOT NULL AUTO_INCREMENT, `time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, `sender` int(11) DEFAULT NULL, `receiver` int(11) DEFAULT NULL, `content` text ) I think Facebook (and the iPhone) use this solution. When you go to your mail box, you have the last messages received/sent grouped by Users (friends). So I will take an example. If I have theses messages (THEY ARE ORDERED YET): **Mike** **Tom** **Pam** Mike Mike **John** John Pam **Steve** **Bobby** Steve Steve Bobby Only Message with ** should be returned because they are the LAST messages I sent/received By User. In fact I want the last message of EACH discussion. What is the solution?

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  • Stringing multiple ShellExecute calls

    - by IVlad
    Consider the following code and its executable - runner.exe: #include <iostream> #include <string> #include <windows.h> using namespace std; int main(int argc, char *argv[]) { SHELLEXECUTEINFO shExecInfo; shExecInfo.cbSize = sizeof(SHELLEXECUTEINFO); shExecInfo.fMask = NULL; shExecInfo.hwnd = NULL; shExecInfo.lpVerb = "open"; shExecInfo.lpFile = argv[1]; string Params = ""; for ( int i = 2; i < argc; ++i ) Params += argv[i] + ' '; shExecInfo.lpParameters = Params.c_str(); shExecInfo.lpDirectory = NULL; shExecInfo.nShow = SW_SHOWNORMAL; shExecInfo.hInstApp = NULL; ShellExecuteEx(&shExecInfo); return 0; } These two batch files both do what they're supposed to, which is run notepad.exe and run notepad.exe and tell it to try to open test.txt: 1. runner.exe notepad.exe 2. runner.exe notepad.exe test.txt Now, consider this batch file: 3. runner.exe runner.exe notepad.exe This one should run runner.exe and send notepad.exe as one of its command line arguments, shouldn't it? Then, that second instance of runner.exe should run notepad.exe - which doesn't happen. If I print the argc argument, it's 14 for the second instance of runner.exe, and they are all weird stuff like Files\Microsoft, SQL, Files\Common and so on. I can't figure out why this happens. I want to be able to string as many runner.exe calls using command line arguments as possible, or at least 2. How can I do that? I am using Windows 7 if that makes a difference.

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  • How can I control the width of JTextFields in Java Swing?

    - by Jonas
    I am trying to have several JTextFields on a single row, but I don't want them to have the same width. How can I control the width and make some of them wider than others? I want that they together take up 100% of the total width, so it would be good if I could use some kind of weigthing. I have tried with .setColumns() but it doesn't make sense. Here is my code: class Row extends JComponent { public Row() { this.setLayout(new BoxLayout(this, BoxLayout.X_AXIS)); JTextField fld1 = new JTextField("First field"); JTextField fld2 = new JTextField("Second field, should be longer"); JTextField fld3 = new JTextField("Short field"); JTextField fld4 = new JTextField("Another field"); fld1.setBorder(null); fld2.setBorder(null); fld3.setBorder(null); fld4.setBorder(null); fld1.setFocusable(false); fld2.setFocusable(false); fld3.setFocusable(false); fld4.setFocusable(false); fld1.setColumns(5); // makes no sense this.add(fld1); this.add(fld2); this.add(fld3); this.add(fld4); } } this.setLayout(new GridLayout(20,0)); this.add(new Row()); this.add(new Row()); this.add(new Row());

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  • How to efficiently SELECT rows from database table based on selected set of values

    - by Chau Chee Yang
    I have a transaction table of 1 million rows. The table has a field name "Code" to keep customer's ID. There are about 10,000 different customer code. I have an GUI interface allow user to render a report from transaction table. User may select arbitrary number of customers for rendering. I use IN operator first and it works for few customers: SELECT * FROM TRANS_TABLE WHERE CODE IN ('...', '...', '...') I quickly run into problem if I select few thousand customers. There is limitation using IN operator. An alternate way is create a temporary table with only one field of CODE, and inject selected customer codes into the temporary table using INSERT statement. I may then using SELECT A.* FROM TRANS_TABLE A INNER JOIN TEMP B ON (A.CODE=B.CODE) This works nice for huge selection. However, there is performance overhead for temporary table creation, INSERT injection and dropping of temporary table. Do you aware of better solution to handle this situation?

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  • Cocoa-Created PDF Not Rendering Correctly

    - by Matthew Roberts
    I've created a PDF on the iPad, but the problem is when you have a line of text greater than 1 line, the content just goes off the page. This is my code: void CreatePDFFile (CGRect pageRect, const char *filename) { CGContextRef pdfContext; CFStringRef path; CFURLRef url; CFMutableDictionaryRef myDictionary = NULL; path = CFStringCreateWithCString (NULL, filename, kCFStringEncodingUTF8); url = CFURLCreateWithFileSystemPath (NULL, path, kCFURLPOSIXPathStyle, 0); CFRelease (path); myDictionary = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks); NSString *foos = @"Title"; const char *text = [foos UTF8String]; CFDictionarySetValue(myDictionary, kCGPDFContextTitle, CFSTR(text)); CFDictionarySetValue(myDictionary, kCGPDFContextCreator, CFSTR("Author")); pdfContext = CGPDFContextCreateWithURL (url, &pageRect, myDictionary); CFRelease(myDictionary); CFRelease(url); CGContextBeginPage (pdfContext, &pageRect); CGContextSelectFont (pdfContext, "Helvetica", 12, kCGEncodingMacRoman); CGContextSetTextDrawingMode (pdfContext, kCGTextFill); CGContextSetRGBFillColor (pdfContext, 0, 0, 0, 1); NSString *body = @"text goes here"; const char *text = [body UTF8String]; CGContextShowTextAtPoint (pdfContext, 30, 750, text, strlen(text)); CGContextEndPage (pdfContext); CGContextRelease (pdfContext);} Now the issue lies within me writing the text to the page, but the problem is that I can't seem to specify a multi-line "text view".

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  • What are the common programming mistakes in Python?

    - by Paul McGuire
    I was about to tag the recent question in which the OP accidentally shadowed the builtin operator module with his own local operator.py with the "common-mistakes" tag, and I saw that there are a number of interesting questions posted asking for common mistakes to avoid in Java, Ruby, Scala, Clojure, .Net, jQuery, Haskell, SQL, ColdFusion, and so on, but I didn't see any for Python. For the benefit of Python beginners, can we enumerate the common mistakes that we have all committed at one time or another, in the hopes of maybe steering a newbie or two clear of them? (In homage to "The Princess Bride", I call these the Classic Blunders.) If possible, a little supporting explanation on what the problem is, and the generally accepted resolution/workaround, so that the beginning Pythoner doesn't read your answer and say "ok, that's a mistake, how do I fix it?"

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  • Using recursion to to trim a binary tree based on a given min and max value

    - by Justin
    As the title says, I have to trim a binary tree based on a given min and max value. Each node stores a value, and a left/right node. I may define private helper methods to solve this problem, but otherwise I may not call any other methods of the class nor create any data structures such as arrays, lists, etc. An example would look like this: overallRoot _____[50]____________________ / \ __________[38] _______________[90] / \ / _[14] [42] [54]_____ / \ \ [8] [20] [72] \ / \ [26] [61] [83] trim(52, 65); should return: overallRoot [54] \ [61] My attempted solution has three methods: public void trim(int min, int max) { rootFinder(overallRoot, min, max); } First recursive method finds the new root perfectly. private void rootFinder(IntTreeNode node, int min, int max) { if (node == null) return; if (overallRoot.data < min) { node = overallRoot = node.right; rootFinder(node, min, max); } else if (overallRoot.data > max) { node = overallRoot = node.left; rootFinder(node, min, max); } else cutter(overallRoot, min, max); } This second method should eliminate any further nodes not within the min/max, but it doesn't work as I would hope. private void cutter(IntTreeNode node, int min, int max) { if (node == null) return; if (node.data <= min) { node.left = null; } if (node.data >= max) { node.right = null; } if (node.data < min) { node = node.right; } if (node.data > max) { node = node.left; } cutter(node.left, min, max); cutter(node.right, min, max); } This returns: overallRoot [54]_____ \ [72] / [61] Any help is appreciated. Feel free to ask for further explanation as needed.

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  • MVC: model of type Nullable<T>

    - by Fyodor Soikin
    I have a partial view that inherits from ViewUserControl<Guid?> - i.e. it's model is of type Nullable<Guid>. Very simple view, nothing special, but that's not the point. Somewhere else, I do Html.RenderPartial( "MyView", someGuid ), where someGuid is of type Nullable<Guid>. Everything's perfectly legal, should work OK, right? But here's the gotcha: the second argument of Html.RenderPartial is of type object, and therefore, Nullable<Guid> being a value type, it must be boxed. But nullable types are somehow special in the CLR, so that when you box one of those, you actually get either a boxed value of type T (Nullable's argument), or a null if the nullable didn't have a value to begin with. And that last case is actually interesting. Turns out, sometimes, I do have a situation when someGuid.HasValue == false. And in those cases, I effectively get a call Html.RenderPartial( "MyView", null ). And what does the HtmlHelper do when the model is null? Believe it or not, it just goes ahead and takes the parent view's model. Regardless of it's type. So, naturally, in those cases, I get an exception saying: "The model item passed into the dictionary is of type 'Parent.View.Model.Type', but this dictionary requires a model item of type 'System.Guid?'" So the question is: how do I make MVC correctly pass new Nullable<Guid> { HasValue = false } instead of trying to grab the parent's model? Note: I did consider wrapping my Guid? in an object of another type, specifically created for this occasion, but this seems completely ridiculous. Don't want to do that as long as there's another way. Note 2: now that I've wrote all this, I've realized that the question may be reduced to how to pass a null for model without ending up with parent's model?

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  • vb.net documentation and exception question

    - by dcp
    Let's say I have this sub in vb.net: ''' <summary> ''' Validates that <paramref name="value"/> is not <c>null</c>. ''' </summary> ''' ''' <param name="value">The object to validate.</param> ''' ''' <param name="name">The variable name of the object.</param> ''' ''' <exception cref="ArgumentNullException">If <paramref name="value"/> is <c>null</c>.</exception> Sub ValidateNotNull(ByVal value As Object, ByVal name As String) If value Is Nothing Then Throw New ArgumentNullException(name, String.Format("{0} cannot be null.", name)) End If End Sub My question is, is it proper to call this ValidateNotNull (which is what I would call it in C#) or should I stick with VB terminology and call it ValidateNotNothing instead? Also, in my exception, is it proper to say "cannot be null", or would it be better to say "cannot be Nothing"? I sort of like the way I have it, but since this is VB, maybe I should use Nothing. But since the exception itself is called ArgumentNullException, it feels weird to make the message say "cannot be Nothing". Anyway, I guess it's pretty nitkpicky, just wondered what you folks thought.

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  • FluentValidation + s#arp

    - by csetzkorn
    Hi, Did someone implement something like this: http://www.jeremyskinner.co.uk/2010/02/22/using-fluentvalidation-with-an-ioc-container/ in s#arp? Thanks. Christian PS: Hi, I have made a start in using FluentValidation in S#arp. I have implemented a Validator factory: public class ResolveType { private static IWindsorContainer _windsorContainer; public static void Initialize(IWindsorContainer windsorContainer) { _windsorContainer = windsorContainer; } public static object Of(Type type) { return _windsorContainer.Resolve(type); } } public class CastleWindsorValidatorFactory : ValidatorFactoryBase { public override IValidator CreateInstance(Type validatorType) { return ResolveType.Of(validatorType) as IValidator; } } I think I will use services which can be used by the controllers etc.: public class UserValidator : AbstractValidator { private readonly IUserRepository UserRepository; public UserValidator(IUserRepository UserRepository) { Check.Require(UserRepository != null, "UserRepository may not be null"); this.UserRepository = UserRepository; RuleFor(user => user.Email).NotEmpty(); RuleFor(user => user.FirstName).NotEmpty(); RuleFor(user => user.LastName).NotEmpty(); } } public interface IUserService { User CreateUser(User User); } public class UserService : IUserService { private readonly IUserRepository UserRepository; private readonly UserValidator UserValidator; public UserService ( IUserRepository UserRepository ) { Check.Require(UserRepository != null, "UserRepository may not be null"); this.UserRepository = UserRepository; this.UserValidator = new UserValidator(UserRepository); } public User CreateUser(User User) { UserValidator.Validate(User); ... } } Instead of putting concrete validators in the service, I would like to use the above factory somehow. Where do I register it and how in s#arp (Global.asax)? I believe s#arp is geared towards the nhibernator validator. How do I deregister it? Thanks. Best wishes, Christian

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  • Returning searched results in an array in Java without ArrayList

    - by Crystal
    I started down this path of implementing a simple search in an array for a hw assignment without knowing we could use ArrayList. I realized it had some bugs in it and figured I'd still try to know what my bug is before using ArrayList. I basically have a class where I can add, remove, or search from an array. public class AcmeLoanManager { public void addLoan(Loan h) { int loanId = h.getLoanId(); loanArray[loanId - 1] = h; } public Loan[] getAllLoans() { return loanArray; } public Loan[] findLoans(Person p) { //Loan[] searchedLoanArray = new Loan[10]; // create new array to hold searched values searchedLoanArray = this.getAllLoans(); // fill new array with all values // Looks through only valid array values, and if Person p does not match using Person.equals() // sets that value to null. for (int i = 0; i < searchedLoanArray.length; i++) { if (searchedLoanArray[i] != null) { if (!(searchedLoanArray[i].getClient().equals(p))) { searchedLoanArray[i] = null; } } } return searchedLoanArray; } public void removeLoan(int loanId) { loanArray[loanId - 1] = null; } private Loan[] loanArray = new Loan[10]; private Loan[] searchedLoanArray = new Loan[10]; // separate array to hold values returned from search } When testing this, I thought it worked, but I think I am overwriting my member variable after I do a search. I initially thought that I could create a new Loan[] in the method and return that, but that didn't seem to work. Then I thought I could have two arrays. One that would not change, and the other just for the searched values. But I think I am not understanding something, like shallow vs deep copying???....

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  • Why does SFINAE not apply to this?

    - by Simon Buchan
    I'm writing some simple point code while trying out Visual Studio 10 (Beta 2), and I've hit this code where I would expect SFINAE to kick in, but it seems not to: template<typename T> struct point { T x, y; point(T x, T y) : x(x), y(y) {} }; template<typename T, typename U> struct op_div { typedef decltype(T() / U()) type; }; template<typename T, typename U> point<typename op_div<T, U>::type> operator/(point<T> const& l, point<U> const& r) { return point<typename op_div<T, U>::type>(l.x / r.x, l.y / r.y); } template<typename T, typename U> point<typename op_div<T, U>::type> operator/(point<T> const& l, U const& r) { return point<typename op_div<T, U>::type>(l.x / r, l.y / r); } int main() { point<int>(0, 1) / point<float>(2, 3); } This gives error C2512: 'point<T>::point' : no appropriate default constructor available Given that it is a beta, I did a quick sanity check with the online comeau compiler, and it agrees with an identical error, so it seems this behavior is correct, but I can't see why. In this case some workarounds are to simply inline the decltype(T() / U()), to give the point class a default constructor, or to use decltype on the full result expression, but I got this error while trying to simplify an error I was getting with a version of op_div that did not require a default constructor*, so I would rather fix my understanding of C++ rather than to just do what works. Thanks! *: the original: template<typename T, typename U> struct op_div { static T t(); static U u(); typedef decltype(t() / u()) type; }; Which gives error C2784: 'point<op_div<T,U>::type> operator /(const point<T> &,const U &)' : could not deduce template argument for 'const point<T> &' from 'int', and also for the point<T> / point<U> overload.

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  • Help Modifying Generic REST Helper PHP Example Code to Support XML DOM

    - by Jennifer Baker
    Hi! I found this example PHP source code at HTTP POST from PHP, without cURL I need some help modifying the example PHP source to support XML DOM for manipulating a REST API. I thought that if I update the CASE statement for the XML section below from $r = simplexml_load_string($res); to $r = new DOMDocument(); $r->load($res); that it would work but it doesn't. :( Any help would be appreciated. function rest_helper($url, $params = null, $verb = 'GET', $format = 'xml') { $cparams = array( 'http' => array( 'method' => $verb, 'ignore_errors' => true ) ); if ($params !== null) { $params = http_build_query($params); if ($verb == 'POST') { $cparams['http']['content'] = $params; } else { $url .= '?' . $params; } } $context = stream_context_create($cparams); $fp = fopen($url, 'rb', false, $context); if (!$fp) { $res = false; } else { // If you're trying to troubleshoot problems, try uncommenting the // next two lines; it will show you the HTTP response headers across // all the redirects: // $meta = stream_get_meta_data($fp); // var_dump($meta['wrapper_data']); $res = stream_get_contents($fp); } if ($res === false) { throw new Exception("$verb $url failed: $php_errormsg"); } switch ($format) { case 'json': $r = json_decode($res); if ($r === null) { throw new Exception("failed to decode $res as json"); } return $r; case 'xml': $r = simplexml_load_string($res); if ($r === null) { throw new Exception("failed to decode $res as xml"); } return $r; } return $res; }

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  • Rails: link_to_remote prototype helper with :with option

    - by Syed Aslam
    I am trying to grab the current value of a drop down list with Prototype and passing it along using :with like this <%= link_to_remote "today", :update => "choices", :url => { :action => "check_availability" } , :with => "'practitioner='+$F('practitioner')&'clinic='+$F('clinic')&'when=today'", :loading => "spinner.show(); $('submit').disable();", :complete => "spinner.hide(); $('submit').enable();" %> However, this is not working as expected. I am unable to access parameters in the controller as the link_to_remote helper is sending parameters like this: Parameters: {"succ"=>"function () {\n return this + 1;\n}", "action"=>"check_availability", "round"=>"function () {\n return __method.apply(null, [this].concat($A(arguments)));\n}", "ceil"=>"function () {\n return __method.apply(null, [this].concat($A(arguments)));\n}", "floor"=>"function () {\n return __method.apply(null, [this].concat($A(arguments)));\n}", "times"=>"function (iterator, context) {\n $R(0, this, true).each(iterator, context);\n return this;\n}", "toPaddedString"=>"function (length, radix) {\n var string = this.toString(radix || 10);\n return \"0\".times(length - string.length) + string;\n}", "toColorPart"=>"function () {\n return this.toPaddedString(2, 16);\n}", "abs"=>"function () {\n return __method.apply(null, [this].concat($A(arguments)));\n}", "controller"=>"main"} Where am I going wrong? Is there a better way to do this?

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  • NullPointerException with static variables

    - by tomekK
    I just hit very strange (to me) behaviour of java. I have following classes: public abstract class Unit { public static final Unit KM = KMUnit.INSTANCE; public static final Unit METERS = MeterUnit.INSTANCE; protected Unit() { } public abstract double getValueInUnit(double value, Unit unit); protected abstract double getValueInMeters(double value); } And: public class KMUnit extends Unit { public static final Unit INSTANCE = new KMUnit(); private KMUnit() { } //here are abstract methods overriden } public class MeterUnit extends Unit { public static final Unit INSTANCE = new MeterUnit(); private MeterUnit() { } ///abstract methods overriden } And my test case: public class TestMetricUnits extends TestCase { @Test public void testConversion() { System.out.println("Unit.METERS: " + Unit.METERS); System.out.println("Unit.KM: " + Unit.KM); double meters = Unit.KM.getValueInUnit(102.11, Unit.METERS); assertEquals(0.10211, meters, 0.00001); } } 1) MKUnit and MeterUnit are both singletons initialized statically, so during class loading. Constructors are private, so they can't be initialized anywhere else. 2) Unit class contains static final references to MKUnit.INSTANCE and MeterUnit.INSTANCE I would expect that: KMUnit class is loaded and instance is created. MeterUnit class is loaded and instance is created. Unit class is loaded and both KM and METERS variable are initialized, they are final so they cant be changed. But when I run my test case in console with maven my result is: T E S T S Running de.audi.echargingstations.tests.TestMetricUnits Unit.METERS: m Unit.KM: null Tests run: 3, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.089 sec <<< FAILURE! - in de.audi.echargingstations.tests.TestMetricUnits testConversion(de.audi.echargingstations.tests.TestMetricUnits) Time elapsed: 0.011 sec <<< ERROR! java.lang.NullPointerException: null at de.audi.echargingstations.tests.TestMetricUnits.testConversion(TestMetricUnits.java:29) Results : Tests in error: TestMetricUnits.testConversion:29 NullPointer And the funny part is that, when I run this test from eclipse via JUnit runner everything is fine, I have no NullPointerException and in console I have: Unit.METERS: m Unit.KM: km So the question is: what can be the reason that KM variable in Unit is null (and in the same time METERS is not null)

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  • How to provide js-ctypes in a spidermonkey embedding?

    - by Triston J. Taylor
    Summary I have looked over the code the SpiderMonkey 'shell' application uses to create the ctypes JavaScript object, but I'm a less-than novice C programmer. Due to the varying levels of insanity emitted by modern build systems, I can't seem to track down the code or command that actually links a program with the desired functionality. method.madness This js-ctypes implementation by The Mozilla Devs is an awesome addition. Since its conception, scripting has been primarily used to exert control over more rigorous and robust applications. The advent of js-ctypes to the SpiderMonkey project, enables JavaScript to stand up and be counted as a full fledged object oriented rapid application development language flying high above 'the bar' set by various venerable application development languages such as Microsoft's VB6. Shall we begin? I built SpiderMonkey with this config: ./configure --enable-ctypes --with-system-nspr followed by successful execution of: make && make install The js shell works fine and a global ctypes javascript object was verified operational in that shell. Working with code taken from the first source listing at How to embed the JavaScript Engine -MDN, I made an attempt to instantiate the JavaScript ctypes object by inserting the following code at line 66: /* Populate the global object with the ctypes object. */ if (!JS_InitCTypesClass(cx, global)) return NULL; /* I compiled with: g++ $(./js-config --cflags --libs) hello.cpp -o hello It compiles with a few warnings: hello.cpp: In function ‘int main(int, const char**)’: hello.cpp:69:16: warning: converting to non-pointer type ‘int’ from NULL [-Wconversion-null] hello.cpp:80:20: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings] hello.cpp:89:17: warning: NULL used in arithmetic [-Wpointer-arith] But when you run the application: ./hello: symbol lookup error: ./hello: undefined symbol: JS_InitCTypesClass Moreover JS_InitCTypesClass is declared extern in 'dist/include/jsapi.h', but the function resides in 'ctypes/CTypes.cpp' which includes its own header 'CTypes.h' and is compiled at some point by some command during 'make' to yeild './CTypes.o'. As I stated earlier, I am less than a novice with the C code, and I really have no idea what to do here. Please give or give direction to a generic example of making the js-ctypes object functional in an embedding.

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  • REST/ROA Architecture - Send database search/querying/filter/sorting parameters in URL? (>, <, IN, e

    - by DutrowLLC
    I'm building a REST interface to my application using ROA (Resource Oriented Architecture) . I'd like to give the client the ability to specify search parameters in URL. So a client could say "Give me all people who's: "first_name" is equal to "BOB" "age" is greater than "30" sort by "last_name" I was thinking something like: GET /PEOPLE/{query_parameters}/{sort_parameters} ...or perhaps GET /PEOPLE?query=<query_string>&sort=<sort_string> ...but I'm unsure what syntax would be good for specifying in the COLUMN_NAME-OPERATOR-VALUE triplicates. I was thinking perhaps something like: column_name.operator.value So the client could say: GET /PEOPLE?query=first_name.EQUALS.bob&query=age.GREATER_THAN.30&sort=last_name.ASCENDING I really don't want to re-invent the wheel here, are there some accepted ways that this is done? I am using Restlets, I don't know if that makes a difference.

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  • Order in many to many relation in Django model

    - by Pietro Speroni
    I am writing a small website to store the papers I have written. The relation papers<- author is important, but the order of the name of the authors (which one is First Author, which one is second order, and so on) is also important. I am just learning Django so I don't know much. In any case so far I have done: from django.db import models class author(models.Model): Name = models.CharField(max_length=60) URLField = models.URLField(verify_exists=True, null=True, blank=True) def __unicode__(self): return self.Name class topic(models.Model): TopicName = models.CharField(max_length=60) def __unicode__(self): return self.TopicName class publication(models.Model): Title = models.CharField(max_length=100) Authors = models.ManyToManyField(author, null=True, blank=True) Content = models.TextField() Notes = models.TextField(blank=True) Abstract = models.TextField(blank=True) pub_date = models.DateField('date published') TimeInsertion = models.DateTimeField(auto_now=True) URLField = models.URLField(verify_exists=True,null=True, blank=True) Topic = models.ManyToManyField(topic, null=True, blank=True) def __unicode__(self): return self.Title This work fine in the sense that I now can define who the authors are. But I cannot order them. How should I do that? Of course I could add a series of relations: first author, second author,... but it would be ugly, and would not be flexible. Any better idea? Thanks

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  • Which are your favorite programming language gadgets?

    - by FerranB
    There are some gadgets/features for programming languages that I like a lot because they save a lot of coding or simply because they are magical or nice. Some of my favorites are: C++ increment/decrement operator: my_array[++c]; C++ assign and sum or substract (...): a += b C# yield return: yield return 1; C# foreach: foreach (MyClass x in MyCollection) PLSQL for loop: for c in (select col1, col2 from mytable) PLSQL pipe row: for i in 1..x loop pipe row(i); end loop; Python Array access operator: a[:1] PLSQL ref cursors. Which are yours?

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