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• Best architecture for a social media app

  - by Sky

  Hey guys, Im working on promising project that develops a new social media app for web and mobile. We are at begin defining functionalities. Nevertheless, I'm thinking ahead on architecture. So I'm asking: 1 - Whats the best plataform to develop the core of this aplication that will have a Rest API interface. 2 - Whats the best database that will scale and grow with my application. As far as I researched, these were the answers I found most interesting: For database: Cassandra NoSQL DB, amazing scalabilty, amazing write performance, good read performance (will be improved on 0.6). I think i will choose that one. Zookeer for transactions on Cassandra. I think that 2 technologies rly good for that propose. What do you think guys? On the front end that will serve the REST API, i dont have a final candidate. For this one i have questions based on Perfomance X Scalabilty X Fast Development/Maintenance. Java or .Net As far as I researched, brings the best balance of this requisits. Python, pearl and Rail, has the best (Fast Development/Maintenance), but sux on all other. C or C++ I dont even consider, because its (Fast Development/Maintenance) sux... So what do you guy think about it?

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• Perl Script in background

  - by himz

  I have a perl script i made to automatically telnet into different servers . but its interface is only command line. To make it more user friendly for general windows users , i need to make GUI for it . My idea is to make GUI in a language like VB,java ,etc and let that call perl script . my script will run in background in a command prompt and whatever the result it displays back in GUI. Got some success. GUI in vb ,I run an instance of CMD in background ,run perl script in that .But that is wer program fails .As perl script runs in a thread for perl , i only get the output when script completes(rather say when it timeout). i need a mechanism where i can interact with the perl script , take output of script and show to user , then take input from user and so on . Please can you all suggest me some way to actually make this happen. PS: No limitation on using any language for GUI (as core work is done by perl script,GUI only there to give appropriate commands to script) Thanks in advance

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• How to avoid using this in a constructor

  - by Paralife

  I have this situation: interface MessageListener { void onMessageReceipt(Message message); } class MessageReceiver { MessageListener listener; public MessageReceiver(MessageListener listener, other arguments...) { this.listener = listener; } loop() { Message message = nextMessage(); listener.onMessageReceipt(message); } } and I want to avoid the following pattern: (Using the this in the Client constructor) class Client implements MessageListener { MessageReceiver receiver; MessageSender sender; public Client(...) { receiver = new MessageReceiver(this, other arguments...); sender = new Sender(...); } . . . @Override public void onMessageReceipt(Message message) { if(Message.isGood()) sender.send("Congrtulations"); else sender.send("Boooooooo"); } } The reason why i need the above functionality is because i want to call the sender inside the onMessageReceipt() function, for example to send a reply. But I dont want to pass the sender into a listener, so the only way I can think of is containing the sender in a class that implements the listener, hence the above resulting Client implementation. Is there a way to achive this without the use of 'this' in the constructor? It feels bizare and i dont like it, since i am passing myself to an object(MessageReceiver) before I am fully constructed. On the other hand, the MessageReceiver is not passed from outside, it is constructed inside, but does this 'purifies' the bizarre pattern? I am seeking for an alternative or an assurance of some kind that this is safe, or situations on which it might backfire on me.

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• Problem consuming Exchange Web Service 2010 with jax-ws metro

  - by Johan Karlberg

  I am trying to consume the Exchange 2010 Web Service interface using JAX-WS. I'm using JAX-WS 2.2 RI (Metro 2.0). 2.1 exhibited the same problem. I am running into trouble with Exchange, which returns "HTTP/1.1 415 Cannot process the message because the content type 'text/xml;charset=utf-8' was not the expected type 'text/xml; charset=utf-8'." as a reponse (2.1 quoted the charset value, otherwise same response). Apparently I need to dictate the exact Content-type header for Exchange to be happy. Is there a way for me to do this without forcing me to manually rebuild the dependency? I currently rely on published maven artifacts, and would like to continue doing this if at all possible. The consuming process is a regular J2SE app, with no containers in sight. I have control of the application and can add pretty much anything required to the applications scope, but can not add out-of-process items like proxy servers. The client classes were generated from local WSDL, but the charset specification is derived from constants declared in the jaxws RI implementation, not the generated code. The resulting HTTP transport is thus handled by the standard http/https client from Sun JRE5 or JRE6.

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• Should I use a collection here?

  - by Eva

  So I have code set up like this: public interface IInterface { public void setField(Object field); } public abstract class AbstractClass extends JPanel implements IInterface { private Object field_; public void setField(Object field) { field_ = field; } } public class ClassA extends AbstractClass { public ClassA() { // unique ClassA constructor stuff } public Dimension getPreferredSize() { return new Dimension(1, 1); } } public class ClassB extends AbstractClass { public ClassB() { // unique ClassB constructor stuff } public Dimension getPreferredSize() { return new Dimension(42, 42); } } public class ConsumerA { public ConsumerA(Collection<AbstractClass> collection) { for (AbstractClass abstractClass : collection) { abstractClass.setField(this); abstractClass.repaint(); } } } All hunky-dory so far, until public class ConsumerB { // Option 1 public ConsumerB(ClassA a, ClassB b) { methodThatOnlyTakesA(a); methodThatOnlyTakesB(b); } // Option 2 public ConsumerB(Collection<AbstractClass> collection) { for (IInterface i : collection) { if (i instanceof ClassA) { methodThatOnlyTakesA((ClassA) i); else if (i instanceof ClassB) { methodThatOnlyTakesB((ClassB) i); } } } } public class UsingOption1 { public static void main(String[] args) { ClassA a = new ClassA(); ClassB b = new ClassB(); Collection<AbstractClass> collection = Arrays.asList(a, b); ConsumerA consumerA = new ConsumerA(collection); ConsumerB consumerB = new ConsumerB(a, b); } } public class UsingOption2 { public static void main(String[] args) { Collection<AbstractClass> collection = Arrays.asList(new ClassA(), new ClassB()); ConsumerA = new ConsumerA(collection); ConsumerB = new ConsumerB(collection); } } With a lot more classes extending AbstractClass, both options get unwieldly. Option1 would make the constructor of ConsumerB really long. Also UsingOption1 would get long too. Option2 would have way more if statements than I feel comfortable with. Is there a viable Option3? If it helps, ClassA and ClassB have all the same methods, they're just implemented differently. Thanks for slogging through my code!

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• Mocking an object that uses jni using EasyMock

  - by Visage

  So my class under test has code that looks braodly like this public void doSomething(int param) { Report report = new Report() ...do some calculations report.someMethod(someData) } my intention was to extract the construction of report into a protected method and override it to use a mock object that I could then test to ensure that someMethod had been called with the right data. So far so good. But Report isnt under my control, and to mkae things worse it uses JNI to load a library at runtime. If I do Report report = EasyMock.createMock(Report.class) then EasyMock attempts to use reflection to find out the class members, but this causes an attempt to load the JNI library, which fails (the JNI libraries are only available on UNIX). Im considering two things: a) Introduce a ReportWrapper interface with two implementations, one of which will delegate calls to an real Report (so basically a Proxy), and a second which will basically use a mock object. or b) instead of calling someMethod, call a protected method which will in turn call someMethod that I can override in a testing subclass. Either way it seems nasty. Any better ways?

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• Hibernate ManyToMany and superclass mapping problem

  - by Jesus Benito

  Hi all, I need to create a relation in Hibernate, linking three tables: Survey, User and Group. The Survey can be visible to a User or to a Group, and a Group is form of several Users. My idea was to create a superclass for User and Group, and create a ManyToMany relationship between that superclass and Survey. My problem is that Group, is not map to a table, but to a view, so I can't split the fields of Group among several tables -which would happen if I created a common superclass-. I thought about creating a common interface, but mapping to them is not allowed. I will probably end up going for a two relations solution (Survey-User and Survey-Group), but I don't like too much that approach. I thought as well about creating a table that would look like: Survey Id | ElementId | Type ElementId would be the Group or UserId, and the type... the type of it. Does anyone know how to achieve it using hibernate annotations? Any other ideas? Thanks a lot

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• Method return type

  - by sarah xia

  Hi, In my company, a system is designed to have 3 layers. Layer1 is responsible for business logic handling. Layer3 is calling back end systems. Layer2 sits between the two layers so that layer1 doesn't need to know about the back end systems. To replay information from layer3, layer2 needs to define interface to layer1. For example, layer1 wants to check if a PIN from user is correct. It calls layer2 checkPin() method and then layer2 calls the relevant back end system. The checkPin() results could be: correctPin, inCorrectPin and internalError. At the moment, we defined the return type 'int'. So if layer2 returns 0, it means correctPin; if 1 is returned, it means inCorrectPin; if 9 is returned it means internalError. It works. However I feel a bit uneasy about this approach. Are there better ways to do it? For example define an enum CheckPinResult{CORRECT_PIN,INCORRECT_PIN,INTERNAL_ERROR}, and return CheckPinResult type? Thanks, Sarah

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• Help to Install Eclipse for A Netbeans Users

  - by Yan Cheng CHEOK

  I had been using Netbeans all the while to develop Swing application. So far, I am a Happy Netbeans User Currently, I had a project (GWT, J2EE and Swing), which I need to use Eclipse (Please do not ask Why) Here is the step I had been taken. Download Eclipse IDE for Java EE Developers (190 MB) from http://www.eclipse.org/downloads/ I thought this should be the correct choice, as I see most features are found in that edition http://www.eclipse.org/downloads/packages/compare-packages After struggling a while to get use to the user interface of Eclipse, I still cannot find a Visual GUI Editor! After doing some Googling, I realize I need to install something called Plugins However, tones of plugins which had similar features has confused me, as I found http://www.cloudgarden.com/jigloo/index.html http://www.eclipse.org/vep/WebContent/main.php http://code.google.com/p/visualswing4eclipse/ This makes me even more confuse? Which plugin I should use to develop a Swing based application? Most of them seems not up-to-dated. Or, is there any complete bundle I can download, where 1 click, will install all the necessary Swing development tools for me? I just miss my Netbeans :( I really appreciate their team, who make the installation work so easy. One click button install, all the necessary tools just come to me

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• JPanel.addComponentListener does not work when the listener is a class variable

  - by Coder

  I have a public class which has the following method and instance variable: public void setImagePanel(JPanel value) { imagePanel = value; if (imagePanel != null) { //method 1 : works imagePanel.addComponentListener(new ComponentAdapter() { public void componentResized(ComponentEvent evt) { System.out.println("Here 1"); } }); //method 2 : does not work panelResizeListener = new ResizeListener(); imagePanel.addComponentListener(panelResizeListener); //method 3 : works //ResizeListener listener = new ResizeListener(); //imagePanel.addComponentListener(listener); //method 4 : works //imagePanel.addComponentListener(new ResizeListener()); //method 5 : does not work -- THIS IS THE DESIRED CODE I WANT TO USE imagePanel.addComponentListener(panelResizeListener); } } public class ResizeListener extends ComponentAdapter { @Override public void componentResized(ComponentEvent evt) { System.out.println("RESIZE 3"); } } private ResizeListener panelResizeListener = new ResizeListener(); Each of the methods above correspond the to code immediately below until the next //method comment. What i don't understand is why i can't use the class instance variable and add that to the JPanel as a component listener. What happens in the cases above where i say that the method does not work is that i don't get the "RESIZE 3" log messages. In all cases where i list that it works, then i get the "RESIZE 3" messages. The outer class is public with no other modification except that it implements an interface that i created (which has no methods or variables in common with the methods and variables listed above). If anyone can help me i would greatly appreciate it. This problem makes no sense to me, the code should be identical.

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• Implementing Drag and Drop using MouseListener for custom Components

  - by Chris Lieb

  I am working on a school assignment that requires me to be able to pick up a tile, drag it to a location, then drop it there. I was able to get this working using TransferHandler and a bunch of stuff from the dnd package, but this is not an acceptable way to perform this action for this assignment according to the professor. So, I am trying to achieve the same effect using the MouseListener interface. The basic setup is this: I have a JPanel-derived class called LocationView that contains JLabel-dervived instances of TileView. I need to get events that give me the LocationView that has the mouse pressed on and the LocationView that has the mouse released on. I am proxying mouse events through the TileView to its containing LocationView so that I can properly handle the mousePressed event. I added System.out.println()'s to the mouse listeners for mousePressed and mouseReleased to both LocationView and TileView so that I could observe the events that were being generated. To my surprise, pressing the mouse on Tile A in Location A, then dragging to Location B and releasing would generate a mouse released event for both Tile A and Location A, but not for Location B. I need the mouse released event triggered for only Location B. To try to work around this, I tried implementing a glass pane based off of the FinalGlassPane found at http://weblogs.java.net/blog/2006/09/20/well-behaved-glasspane. After adding the glass pane and adding an event listener for it, I can see that the mouse events are indeed filtering through the glass pane, but the mouse released event is still only being called on the item the mouse was clicked on. Is there a way to have mousePressed and mouseReleased events associated with the same drag action be called on separate components?

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• How to specify a parameter as part of every web service call?

  - by LES2

  Currently, each web service for our application has a user parameter that is added for every method. For example: @WebService public interface FooWebService { @WebMethod public Foo getFoo(@WebParam(name="alwaysHere",header=true,partName="alwaysHere") String user, @WebParam(name="fooId") Long fooId); @WebMethod public Result deletetFoo(@WebParam(name="alwaysHere",header=true,partName="alwaysHere") String user, @WebParam(name="fooId") Long fooId); // ... } There could be twenty methods in a service, each with the first parameter as user. And there could be twenty web services. We don't actually use the 'user' argument in the implementations - in fact, I don't know why it's there - but I wasn't involved in the design, and the person that put it there had a reason (I hope). Anyway, I'm trying to straighten out this Big Ball of Mud. I have already come a long way by wrapping the web services by a Spring proxy, which allows me to do some before-and-after processing in an interceptor (before there were at least 20 lines of copy-pasted boiler plate per method). I'm wondering if there's some kind of "message header" I can apply to the method or package and that can be accessed by some type of handler or something outside of each web service method. Thanks in advance for the advice, LES

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• How would you code a washing machine?

  - by Dan

  Imagine I have a class that represents a simple washing machine. It can perform following operations in the following order: turn on - wash - centrifuge - turn off. I see two basic alternatives: A) I can have a class WashingMachine with methods turnOn(), wash(int minutes), centrifuge(int revs), turnOff(). The problem with this is that the interface says nothing about the correct order of operations. I can at best throw InvalidOprationException if the client tries to centrifuge before machine was turned on. B) I can let the class itself take care of correct transitions and have the single method nextOperation(). The problem with this on the other hand, is that the semantics is poor. Client will not know what will happen when he calls the nextOperation(). Imagine you implement the centrifuge button’s click event so it calls nextOperation(). User presses the centrifuge button after machine was turned on and ups! machine starts to wash. I will probably need a few properties on my class to parameterize operations, or maybe a separate Program class with washLength and centrifugeRevs fields, but that is not really the problem. Which alternative is better? Or maybe there are some other, better alternatives that I missed to describe?

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• Why is my GUI unresponsive while a SwingWorker thread runs?

  - by Starchy

  Hello, I have a SwingWorker thread with an IOBound task which is totally locking up the interface while it runs. Swapping out the normal workload for a counter loop has the same result. The SwingWorker looks basically like this: public class BackupWorker extends SwingWorker<String, String> { private static String uname = null; private static String pass = null; private static String filename = null; static String status = null; BackupWorker (String uname, String pass, String filename) { this.uname = uname; this.pass = pass; this.filename = filename; } @Override protected String doInBackground() throws Exception { BackupObject bak = newBackupObject(uname,pass,filename); return "Done!"; } } The code that kicks it off lives in a class that extends JFrame: public void actionPerformed(ActionEvent event) { String cmd = event.getActionCommand(); if (BACKUP.equals(cmd)) { SwingUtilities.invokeLater(new Runnable() { public void run() { final StatusFrame statusFrame = new StatusFrame(); statusFrame.setVisible(true); SwingUtilities.invokeLater(new Runnable() { public void run () { statusFrame.beginBackup(uname,pass,filename); } }); } }); } } Here's the interesting part of StatusFrame: public void beginBackup(final String uname, final String pass, final String filename) { worker = new BackupWorker(uname, pass, filename); worker.execute(); try { System.out.println(worker.get()); } catch (InterruptedException e) { e.printStackTrace(); } catch (ExecutionException e) { e.printStackTrace(); } } } So far as I can see, everything "long-running" is handled by the worker, and everything that touches the GUI on the EDT. Have I tangled things up somewhere, or am I expecting too much of SwingWorker?

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• Can not find Driver when using generic database bundle

  - by Marc

  I have a project that is build up from several OSGi bundles. One of them is a generic Database bundle that defines a DataSource that can be used throughout the project. The spring bean definition of this service is: <osgi:service interface="javax.sql.DataSource"> <bean class="org.postgresql.ds.PGPoolingDataSource"> <property name="databaseName" value="xxx" /> <property name="serverName" value="xxx" /> <property name="user" value="xxx" /> <property name="password" value="xxx" /> </bean> </osgi:service> Now, when using this DataSource is a different bundle, we get an error: No suitable driver found for jdbc:postgresql://localhost/xxx I have tried the following to add the org.postgresql.Driver to the DriverManager: Instantiated an empty bean for that Driver in the spring context, like this: <bean class="org.postgresql.Driver" /> Instantiated the Driver statically in one of the classes, like this: Class.forName("org.postgresql.Driver"); Added a file META-INF\services\java.sql.Driver with the content org.postgresql.Driver None of these solutions seems to help.

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• How can I provide users with the functionality of the DBUnit DatabaseOperation methods from a web in

  - by reckoner

  I am currently updating a java-based web application which allows database developers to create stored procedure regression test suites for database testing. Currently, for test setup, execution and clean-up stages, the user is provided with text boxes where they are able to enter SQL code which is executed by the isql command. I would like to extend the application to use DB Unit’s DatabaseOperation methods to provide more ways to setup the state of the database than just SQL statements. The main reason for using Db Unit rather than just SQL statements is to be able to create and store xml and xls DataSets on a server where they can be associated with their test cases and used for data setup. My question is: How can I provide users with the functionality of the DBUnit DatabaseOperation methods from a web interface? I have considered: Creating a simple programming language and a parser to read some simple syntax involving the DB Unit method names which accept a parameter being the file location to an xml or xls DataSet. I was thinking of allowing the user to register the files they need with the web app which would catalogue them and provide each file with an identifier which could passed as a parameter to the methods in this simple programming language. Creating an XML DTD which provides the user with the ability to specify operations and parameters. If I went this approach, how can I execute the methods and their parameters that I parse from the XML document? Creating a table in the database which stores the method and a FK relation to a catalogued DataSet file, however I don’t think this would be good solution due to the fact that data entry would be tedious. Thanks for your help.

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• JBoss Clustered Service that sends emails from txt file

  - by michael lucas

  I need a little push in the right direction. Here's my problem: I have to create an ultra-reliable service that sends email messages to clients whose addresses are stored in txt file on FTP server. Single txt file may contain unlimited number of entries. Most often the file contains about 300,000 entries. Service exposes interface with just two simple methods: TaskHandle sendEmails(String ftpFilePath); ProcessStatus checkProcessStatus(TaskHandle taskHandle); Method sendEmails() returns TaskHandle by which we can ask for ProcessStatus. For such a service to be reliable clustering is necessary. Processing single txt file might take a long time. Restarting one node in a cluster should have no impact on sending emails. We use JBoss AS 4.2.0 which comes with a nice HASingletonController that ensure one instance of service is running at given time. But once a fail-over happens, the second service should continue work from where the first one stopped. How can I share state between nodes in a cluster in such a way that leaves no possibility of sending some emails twice?

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• Poor performance using RMI-proxies with Swing components

  - by Patrick

  I'm having huge performance issues when I add RMI proxy references to a Java Swing JList-component. I'm retrieving a list of user Profiles with RMI from a server. The retrieval itself takes just a second or so, so that's acceptable under the circumstances. However, when I try to add these proxies to a JList, with the help of a custom ListModel and a CellRenderer, it takes between 30-60 seconds to add about 180 objects. Since it is a list of users' names, it's preferrable to present them alphabetically. The biggest performance hit is when I sort the elements as they get added to the ListModel. Since the list will always be sorted, I opted to use the built-in Collections.binarySearch() to find the correct position for the next element to be added, and the comparator uses two methods that are defined by the Profile interface, namely getFirstName() and getLastName(). Is there any way to speed this process up, or am I simply implementing it the wrong way? Or is this a "feature" of RMI? I'd really love to be able to cache some of the data of the remote objects locally, to minimize the remote method calls.

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• Lan Chatting system [closed]

  - by jay prakash singh

  Possible Duplicate: LAN chating system or LAN chat server displaying list of user to all the user window my code is i m use RMI so this is the interface declaration public void sendPublicMessage(String keyword, String username, String message) throws RemoteException; public void sendPrivateMessage(String keyword, String username, String message) throws RemoteException; public ArrayList getClientList() throws RemoteException; public void connect(String username) throws RemoteException; public void disconnect(String username) throws RemoteException; } chat Server here connectedUser is the HasMap object we use the follo0wing code for connection here ChatImpl is the stub try { InetAddress Address = InetAddress.getLocalHost(); ChatImpl csi = new ChatImpl(this); Naming.rebind("rmi://"+Address.getHostAddress()+":1099/ChatService", csi); } public ArrayList getClientList() { ArrayList myUser = new ArrayList(); Iterator i = connectedUser.keySet().iterator(); String user = null; while(i.hasNext()) { user = i.next().toString(); myUser.add(user); } return myUser; } public void addClient(Socket clientSocket) throws RemoteException { connectedUser.put(getUsername(), clientSocket); sendPublicMessage(ONLINE, getUsername(), "CLIENT"); } this is the client side code for array list public void updateClient(ArrayList allClientList) throws RemoteException { listClient.clear(); int i = 0; String username; for(i=0; i<allClientList.size(); i++) { username = allClientList.get(i).toString(); listClient.addElement(username); } }

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• Type-safe mapping from Class<T> to Thing<T>

  - by Joonas Pulakka

  I want to make a map-kind of container that has the following interface: public <T> Thing<T> get(Class<T> clazz); public <T> void put(Class<T> clazz, Thing<T> thing); The interesting point is that the Ts in each Class<T><- Thing<T> pair is the same T, but the container should be able to hold many different types of pairs. Initially I tried a (Hash)Map. But, for instance, Map<Class<T>, Thing<T>> is not right, because then T would be same T for all pairs in that map. Of course, Map<Class<?>, Thing<?>> works, but then I don't have type-safety guarantees so that when I get(String.class), I can't be sure that I get a Thing<String> instance back. Is there a way to accomplish the kind of type safety that I'm looking for?

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• How to deserialize implementation classes in OSGi

  - by Daniel Schneller

  In an eRCP OSGi based application the user can push a button and go to a lock screen similar to that of Windows or Mac OS X. When this happens, the current state of the application is serialized to a file and control is handed over to the lock screen. In this mobile application memory is very tight, so we need to get rid of the original view/controller when the lock screen comes up. This works fine and we end up with a binary serialized file. Once the user logs back in, the file is read in again and the original state of the application restored. This works fine as well, except when the controller that was serialized contained a reference to an object which comes from a different bundle. In my concrete case the original controller (from bundle A) can call a web service and gets a result back. Nothing fancy, just some Strings and Numbers in a simple value holder class. However the controller only sees this as a Result interface; the actual runtime object (ResultImpl) is defined and created in a different bundle (bundle B, the webservice client implementation) and returned via a service call. When the deserialization now tries to thaw the controller from the file, it throws a ClassNotFound exception, complaining about not being able to deserialize the result object, because deserialization is called from bundle A, which cannot see the ResultImpl class from bundle B. Any ideas on how to work around that? The only thing I could come up with is to clone all the individual values into another object, defined in the controller's bundle, but this seems like quite a hassle.

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• garbage collector Issue

  - by Eslam

  this question is like my previous one Given: 3. interface Animal { void makeNoise(); } 4. class Horse implements Animal { 5. Long weight = 1200L; 6. public void makeNoise() { System.out.println("whinny"); } 7. } 8. public class Icelandic extends Horse { 9. public void makeNoise() { System.out.println("vinny"); } 10. public static void main(String[] args) { 11. Icelandic i1 = new Icelandic(); 12. Icelandic i2 = new Icelandic(); 13. Icelandic i3 = new Icelandic(); 14. i3 = i1; i1 = i2; i2 = null; i3 = i1; 15. } 16. } When line 14 is reached, how many objects are eligible for the garbage collector? A. 0 B. 1 C. 2 D. 3 E. 4 F. 6 i choosed A but the right answer is E, but i don't know Why?

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• How to reference an embedded JCA resource adapater

  - by cg

  For our current J2EE project based on JBoss, we need to interface with a remote system using message driven beans and a JCA resource adapter provided as a RAR file by a third party. I would like to package and deploy the entire project as an EAR file to our JBoss server. Most notably, the RAR file should be embedded within the EAR file and not be deployed globally. All of this is working fine so far, but I'm not particularly happy with the way the RAR file is referenced. The jboss.xml packaged with the MDB for example, currently looks like this: <jboss> <enterprise-beans> <message-driven> <ejb-name>testBean1</ejb-name> <resource-adapter-name>test1.ear#thirdparty-1.0.rar</resource-adapter-name> </message-driven> </enterprise-beans> </jboss> While this is generally working fine, it will break when the EAR file is renamed to "test2.ear". Is there a way to reference the embedded RAR file without hard-coding the containing archive's name?

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• Enum exeeding the 65535 bytes limit of static initializer... what's best to do?

  - by Daniel Bleisteiner

  I've started a rather large Enum of so called Descriptors that I've wanted to use as a reference list in my model. But now I've come across a compiler/VM limit the first time and so I'm looking for the best solution to handle this. Here is my error : The code for the static initializer is exceeding the 65535 bytes limit It is clear where this comes from - my Enum simply has far to much elements. But I need those elements - there is no way to reduce that set. Initialy I've planed to use a single Enum because I want to make sure that all elements within the Enum are unique. It is used in a Hibernate persistence context where the reference to the Enum is stored as String value in the database. So this must be unique! The content of my Enum can be devided into several groups of elements belonging together. But splitting the Enum would remove the unique safety I get during compile time. Or can this be achieved with multiple Enums in some way? My only current idea is to define some Interface called Descriptor and code several Enums implementing it. This way I hope to be able to use the Hibernate Enum mapping as if it were a single Enum. But I'm not even sure if this will work. And I loose unique safety. Any ideas how to handle that case?

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• Problem with 2 levels of inheritance in hibernate mapping

  - by Seth

  Here's my class structure: class A class B extends A class C extends A class D extends C class E extends C And here are my mappings (class bodies omitted for brevity): Class A: @Entity @Inheritance(strategy=InheritanceType.SINGLE_TABLE) @MappedSuperclass @DiscriminatorColumn( name="className", discriminatorType=DiscriminatorType.STRING ) @ForceDiscriminator public abstract class A Class B: @Entity @DiscriminatorValue("B") public class B extends A Class C: @Entity @DiscriminatorValue("C") @MappedSuperclass @DiscriminatorColumn( name="cType", discriminatorType=DiscriminatorType.STRING ) @ForceDiscriminator public abstract class C extends A Class D: @Entity @DiscriminatorValue("D") public class D extends C Class E: @Entity @DiscriminatorValue("E") public class E extends C I've got a class F that contains a set of A: @Entity public class F { ... @OneToMany(fetch=FetchType.LAZY, cascade=CascadeType.ALL) @JoinTable( name="F_A", joinColumns = @JoinColumn(name="A_ID"), inverseJoinColumns = @JoinColumn(name="F_ID") ) private Set<A> aSet = new HashSet<A>(); ... The problem is that whenever I add a new E instance to aSet and then call session.saveOrUpdate(fInstance), hibernate saves with "A" as the discrimiator string. When I try to access the aSet in the F instance, I get the following exception (full stacktrace ommitted for brevity): org.hibernate.InstantiationException: Cannot instantiate abstract class or interface: path.to.class.A Am I mapping the classes incorrectly? How am I supposed to map multiple levels of inheritance? Thanks for the help!

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