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  • Spring-MVC Problem using @Controller on controller implementing an interface

    - by layne
    I'm using spring 2.5 and annotations to configure my spring-mvc web context. Unfortunately, I am unable to get the following to work. I'm not sure if this is a bug (seems like it) or if there is a basic misunderstanding on how the annotations and interface implementation subclassing works. For example, @Controller @RequestMapping("url-mapping-here") public class Foo { @RequestMapping(method=RequestMethod.GET) public void showForm() { ... } @RequestMapping(method=RequestMethod.POST) public String processForm() { ... } } works fine. When the context starts up, the urls this handler deals with are discovered, and everything works great. This however does not: @Controller @RequestMapping("url-mapping-here") public class Foo implements Bar { @RequestMapping(method=RequestMethod.GET) public void showForm() { ... } @RequestMapping(method=RequestMethod.POST) public String processForm() { ... } } When I try to pull up the url, I get the following nasty stack trace: javax.servlet.ServletException: No adapter for handler [com.shaneleopard.web.controller.RegistrationController@e973e3]: Does your handler implement a supported interface like Controller? org.springframework.web.servlet.DispatcherServlet.getHandlerAdapter(DispatcherServlet.java:1091) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:874) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:809) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:571) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:501) javax.servlet.http.HttpServlet.service(HttpServlet.java:627) However, if I change Bar to be an abstract superclass and have Foo extend it, then it works again. @Controller @RequestMapping("url-mapping-here") public class Foo extends Bar { @RequestMapping(method=RequestMethod.GET) public void showForm() { ... } @RequestMapping(method=RequestMethod.POST) public String processForm() { ... } } This seems like a bug. The @Controller annotation should be sufficient to mark this as a controller, and I should be able to implement one or more interfaces in my controller without having to do anything else. Any ideas?

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  • How to read a password encrypted key with java?

    - by Denis
    Hi, This is very simple question. I have private key stored in file in PKCS8 DER format and protected by password. What is the easiest way to read it? Here is the code I use to load unencrypted one: InputStream in = new FileInputStream(privateKeyFilename); byte[] privateKeydata = new byte[in.available()]; in.read(privateKeydata); in.close(); KeyFactory privateKeyFactory = KeyFactory.getInstance("RSA"); PKCS8EncodedKeySpec encodedKeySpec = new PKCS8EncodedKeySpec(privateKeydata); PrivateKey privateKey = privateKeyFactory.generatePrivate(encodedKeySpec); Please, Help!!!

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  • Most Efficient Way of calling an external webservice in Java?

    - by Sudheer
    In one of our applications we need to call the Yahoo Soap Webservice to Get Weather and other related info. I used the wsdl2java tool from axis1.4 and generated th required stubs and wrote a client. I use jsp's use bean to include the client bean and call methods defined in the client which call the yahoo webservice inturn. Now the problem: When users make calls to the jsp the response time of the webservice differs greatly, like for one user it took less then 10 seconds and the other in the same network took more than a minute. I was just wondering if Axis1.4 queues the requests even though the jsps are multithreaded. And finally is there an efficient way of calling the webservice(Yahoo weather). Typically i get around 200 simultaneous requests from my users.

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  • A simple free MIDI implementation in Java besides javax.sound.midi: Are there any?

    - by Peterdk
    The problem is: Android doesn't implement javax.sound.midi. I need a simple free library that allows me to create simple 1-track midi files. I searched the net for it, but can't really find anything, since everything uses javax.sound.midi . The license needs to be one where I don't need to opensource my linked app. Any ideas? I also looked into the fileformat itself. However, I am totally not familiar with working with bytes, hexidecimal stuff etc. So, other option is: are there any simple midi implementations that I can use as reference?

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  • Java InputReader. Detect if file being read is binary?

    - by Trizicus
    I had posted a question in regards to this code. I found that JTextArea does not support the binary type data that is loaded. So my new question is how can I go about detecting the 'bad' file and canceling the file I/O and telling the user that they need to select a new file? class Open extends SwingWorker<Void, String> { File file; JTextArea jta; Open(File file, JTextArea jta) { this.file = file; this.jta = jta; } @Override protected Void doInBackground() throws Exception { BufferedReader br = null; try { br = new BufferedReader(new FileReader(file)); String line = br.readLine(); while(line != null) { publish(line); line = br.readLine(); } } finally { try { br.close(); } catch (IOException e) { } } return null; } @Override protected void process(List<String> chunks) { for(String s : chunks) jta.append(s + "\n"); } }

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  • Is testability alone justification for dependency injection?

    - by fearofawhackplanet
    The advantages of DI, as far as I am aware, are: Reduced Dependencies More Reusable Code More Testable Code More Readable Code Say I have a repository, OrderRepository, which acts as a repository for an Order object generated through a Linq to Sql dbml. I can't make my orders repository generic as it performs mapping between the Linq Order entity and my own Order POCO domain class. Since the OrderRepository by necessity is dependent on a specific Linq to Sql DataContext, parameter passing of the DataContext can't really be said to make the code reuseable or reduce dependencies in any meaningful way. It also makes the code harder to read, as to instantiate the repository I now need to write new OrdersRepository(new MyLinqDataContext()) which additionally is contrary to the main purpose of the repository, that being to abstract/hide the existence of the DataContext from consuming code. So in general I think this would be a pretty horrible design, but it would give the benefit of facilitating unit testing. Is this enough justification? Or is there a third way? I'd be very interested in hearing opinions.

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  • How does a Java Arraylist contains() method evalute objects?

    - by mvid
    Say i create one object and add it to my ArrayList. If I then create another object with exactly the same constructor input, will the contain() method evaluate the two objects to be the same? Assume the constructor doesn't do anything funny with the input, and the variables stored in both objects are identical. ArrayList<Thing> basket = new ArrayList<Thing>(); Thing thing = new Thing(100); basket.add(thing); Thing another = new Thing(100); basket.contains(another); // true or false?

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  • Private Java class properties mysteriously reset between method calls....

    - by Michael Jones
    I have a very odd problem. A class property is mysteriously reset between method calls. The following code is executed so the constructor is called, then the parseConfiguration method is called. Finally, processData is called. The parseConfiguration method sets the "recursive" property to "true". However, as soon as it enters "processData", "recursive" becomes "false". This problem isn't isolated to a single class -- I have several examples of this in my code. How can this possibly be happening? I've tried initialising properties when they're declared outside any methods, I've tried initialising them in constructors... nothing works. The only complication I can think of here is that this class is invoked by an object that runs in a thread -- but here is one instance per thread, so surely no chance that threads are interfering. I've tried setting both methods to "synchronized", but this still happens. Please help! /** * This class or its superclasses are NOT threaded and don't extend Thread */ public class DirectoryAcquirer extends Manipulator { /** * @var Whether to recursively scan directories */ private boolean recursive = false; /** * Constructor */ public DirectoryAcquirer() { } /** * Constructor that initialises the configuration * * @param config * @throws InvalidConfigurationException */ public DirectoryAcquirer(HierarchicalConfiguration config) throws InvalidConfigurationException { super(config); } @Override protected void parseConfiguration() throws InvalidConfigurationException { // set whether to recurse into directories or not if (this.config.containsKey("recursive")) { // this.recursive gets set to "true" here this.recursive = this.config.getBoolean("recursive"); } } @Override public EntityCollection processData(EntityCollection data) { // here this.recursive is "false" this.logger.debug("processData: Entered method"); } }

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  • Am I doing getters/setters the right way in Java?

    - by Sergio Tapia
    public class Persona { int Codigo; String Nombre; public Persona(int Codigo, String Nombre){ this.Codigo = Codigo; this.Nombre = Nombre; } public void setCodigo(int Codigo){ this.Codigo = Codigo; } public int getCodigo(){ return this.Codigo; } public void setNombre(String Nombre){ this.Nombre = Nombre; } public String getNombre(){ return this.Nombre; } } Or is there a much shorter (realiable) way to do it?

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  • State pattern: Why doesn't the context class implement or inherit the State abstract interface/class

    - by Ricket
    I'm reading about the State pattern. I have only just begun, so of course I begin by reading the entire Wikipedia article on it. I noticed that both of the examples in the article have some base abstract class or Java interface for a generic State's methods/functions. Then there are some states which inherit from the base and implement those methods/functions in different ways. Then there's a Context class which has a private member of type State and which, at any time, can be equal to an instance of one of the implementations. That context class also implements the same methods, and passes them onto the current state instance, and then has an additional method to change the state (or depending on design I understand the change of state could be a reaction to one of the implemented methods). Why doesn't this context class specifically "extend" or "implement" the generic State base class/interface?

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  • How to represent a Board Panel in Java for a game ?

    - by FILIaS
    I wanna fix a 2D board for a game. I've already fixed other panels for the Gui and everything goes well. But the panel for the board cant be printed on the window. I'm a bit confused about it as i think i've followed the same ideas as for the others panels i need. Here's what i've done: EDIT:*EDIT* what i'm trying to do is fix a board panel for the game according to the dimensions of the it,hold every square in an array in order to use it after wherever it;s needed. I draw each little square of it with the method draw and put it back to the panel. So, each square on the board is a panel. This is the idea. But as u can see. There are troubles/errors on it. EDIT: code updated. just found a part of the problem. i thought first that i had set background to squared, but i didnt. with this one it appears on the panel a wide black "column". Unfortunately,still none squares. :( One More EDIT: Also,i realized that draw method is never called. when i put the draw method in the following method i can see the squares but they remain small. I redefine them with setSize but still no change. How can I use paint method to edit the panels properly???? As it is now it can't. Even it can't return an object(eg panel) as it's polymorphic void! /** *Method used to construct the square in the area of the *gui's grid. In this stage a GUISquare array is being constructed, * used in the whole game as *a mean of changing a square graphical state. *@param squares is the squares array from whom the gui grid will be *constructed. *@see getSquare about the correspondance beetween a squareModel and * a GUISquare. */ private void initBoardPanel(SquareModel[][] squares){ BoardPanel.setLayout(new GridLayout(height ,width )); //set layout SquareRenderer[][] Squares; JPanel[][] grid; Squares=new GUISquare[height][width()]; grid=new JPanel[height()][width()]; for (int i=0; i<height(); i++){ for (int j=0; j<width() ; j++){ SquareRenderer kou=new SquareRenderer(i,j); kou.setSquare(myGame.getSquares()[i][j]); //NOTE: THE FOLLOWING DRAW METHOD CANT BE CALLED!!!? if (myGame.getSquares()[i][j] instanceof SimpleSq ){ kou .paintPanel(i,j,"");} else if (myGame.getSquares()[i][j] instanceof ActionSq ) { kou .paintPanel(i,j); } //JUST BECAUSE DRAW CANT BE CALLED I PUT ITS CODE HERE: //JUST TO CHECK: JPanel panel = new JPanel(); panel.setLayout(new BorderLayout()); JLabel label1 = new JLabel("Move To "+myGame.getSquares()[i][j].getGoTo()); JLabel label2 = new JLabel(""+myGame.getSquares()[i][j].getSquare()); panel.setBackground(Color.ORANGE); panel.add(label2, BorderLayout.NORTH); panel.add(label1, BorderLayout.CENTER); panel.setSize(250,250); ///////// <--until here ---paint method<--- kou.add(panel); kou.setVisible(true); kou.setBackground(Color.BLACK); Squares[i][j]= kou; BoardPanel.add(kou); BoardPanel.setVisible(true); BoardPanel.setBackground(Color.WHITE); } } this.add(BoardPanel,BorderLayout.WEST); // this.pack(); //sets appropriate size for frame this.setVisible(true); //makes frame visible } IMPLEMENTED BY SQUARERENDERER: /** * Transformer for Snake/Ladder * <br>This method is used to display a square on the screen. */ public void paintPanel(int i,int j) { JPanel panel = new JPanel(); panel.setLayout(new BorderLayout()); JLabel label1 = new JLabel("Move To"+myGame.getSquares()[i][j].getGoTo()); JLabel label2 = new JLabel(""+myGame.getSquares()[i][j].getSquare()); JSeparator CellSeparator = new JSeparator(orientation); panel.add(CellSeparator); panel.setForeground(Color.ORANGE); panel.add(label2, BorderLayout.NORTH); panel.add(label1, BorderLayout.CENTER); }

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  • Java: how to tell if a line in a text file was supposed to be blank?

    - by defn
    I'm working on a project in which I have to read in a Grammar file (breaking it up into my data structure), with the goal of being able to generate a random "DearJohnLetter". My problem is that when reading in the .txt file, I don't know how find out whether the file was supposed to be a completely blank line or not, which is detrimental to the program. Here is an example of part of the file, How do i tell if the next line was supposed to be a blank line? (btw I'm just using a buffered reader) Thanks! <start> I have to break up with you because <reason> . But let's still <disclaimer> . <reason> <dubious-excuse> <dubious-excuse> , and also because <reason> <dubious-excuse> my <person> doesn't like you I'm in love with <another> I haven't told you this before but <harsh> I didn't have the heart to tell you this when we were going out, but <harsh> you never <romantic-with-me> with me any more you don't <romantic> any more my <someone> said you were bad news

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  • Repeating fields in similar database tables

    - by user1738833
    I have been tasked with working on a database that I have never seen before and I'm looking at the DB structure. Some of the central and most heavily queried and joined tables look like virtual duplicates of each other. Here's a massively simplified representation of the situation, with business-sensitive information changed, listing hypothetical table names and fields: TopLevelGroup: PK_TLGroupId, DisplaysXOnBill, DisplaysYOnBill, IsInvoicedForJ, IsInvoicedForK SubGroup: PK_SubGroupId, FK_ParentTopLevelGroupId, DisplaysXOnBill, DisplaysYOnBill, IsInvoicedForJ, IsInvoicedForK SubSubGroup: PK_SubSUbGroupId, FK_ParentSubGroupId, DisplaysXOnBill, DisplaysYOnBill, IsInvoicedForJ, IsInvoicedForK I haven't listed the types of the fields as I don't think it's particularly important to the situation. In addition, it's worth saying that rather than four repeated fields as in the example above, I'm looking at 86 repeated fields. For the most part, those fields genuinely do represent "facts" about the primary table entity, so it's not automatically wrong for that reason. In addition, the "groups" represented here have a property inheritance relationship. If DisplaysXOnBill is NULL in the SubSubGroup, it takes the value of DisplaysXOnBillfrom it's parent, the SubGroup, and so-on up to the TopLevelGroup. Further, the requirements will never require that the model extends beyond three levels, so there is no need for flexibility in that area. Is there a design smell from several tables which describe very similar entities having almost identical fields? If so, what might be a better design of the example above? I'm using the phrase "design smell" to indicate a possible problem. Of course, in any given situation, a particular design might well be the best solution. I'm looking for a more general answer - wondering what might be wrong with this design and what might be the better design were that the case. Possibly related, but not primary questions: Is this database schema in a reasonably normal form (e.g. to 3NF), insofar as can be told from the information I've provided. I can't see a problem with the requirements of 2NF and 3NF, except in their inheriting the requirements of 1NF. Is 1NF satisfied though? Are repeating groups allowed in different tables? Is there a best-practice method for implementing the inheritance relationship in a database as I require? The method above feels clunky to me because any query on the SubSubGroup necessarily needs to join onto the SubGroup and the TopLevelGroup tables to collect inherited facts, which can make even trivial joins requiring facts from the SubSubGroup table rather long-winded. There are, of course, political considerations to making a relatively large change like this. For the purpose of this question, I'm happy to ignore that fact in the interests of keeping the answers ring-fenced to the technical problem.

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  • Java: Sharing a connection pool accross other J2SE Apps...?

    - by Zombies
    So I have a connection pool setup. Which is great and all since I have an application that really needs it. However what I would like to know is if it is possible to share this connection pool with other J2SE apps? Would this even be worth it, as opposed to creating a connection pool based on each apps needs? If it would be prudent, how can I accomplish this?

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  • How to create extensible dynamic array in Java without using pre-made classes?

    - by AndrejaKo
    Yeah, it's a homework question, so givemetehkodezplsthx! :) Anyway, here's what I need to do: I need to have a class which will have among its attributes array of objects of another class. The proper way to do this in my opinion would be to use something like LinkedList, Vector or similar. Unfortunately, last time I did that, I got fire and brimstone from my professor, because according to his belief I was using advanced stuff without understanding basics. Now next obvious solution would be to create array with fixed number of elements and add checks to get and set which will see if the array is full. If it is full, they'd create new bigger array, copy older array's data to the new array and return the new array to the caller. If it's mostly empty, they'd create new smaller array and move data from old array to new. To me this looks a bit stupid. For my homework, there probably won't be more that 3 elements in an array, but I'd like to make a scalable solution without manually calculating statistics about how often is array filled, what is the average number of new elements added, then using results of calculation to calculate number of elements in new array and so on. By the way, there is no need to remove elements from the middle of the array. Any tips?

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  • Problems importing WAR files in Eclipse?

    - by CitadelCSAlum
    I was unfortunately forced to result to uploading a WAR file as my backup for a web application I am working on. Luckily I have the most recent WAR file available. I am using Eclipse IDE and am using the Web Tools plugin for all the J2EE work that I am doing with the Dynamic Web Application Project. When I imported my WAR file, and ran it on a local server, everything works fine. The problem I a ran into is that in the Java Resources/src folder that all my packages and .java files were now only consists of all the same packages, but they are empty. I checked to see if I could find the files and I found the .class files in an "Imported files" folder that is not accessible in the Eclipse Project Explorer. I believe that I need to do some type of build or something so that my .java files are available for me, but unfortunately this is one area where I lack. One thing I would also like to know is, one way or the other, am I able to obtain the .java source code files if I have access to the .class files? Also, I would like to configure this environment as it was before where my Java Resources:src folder contaiend the packages and .java files.

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