Search Results

Search found 46894 results on 1876 pages for 'java native interface'.

Page 972/1876 | < Previous Page | 968 969 970 971 972 973 974 975 976 977 978 979  | Next Page >

  • Adding to existing JList

    - by Máca Danilov
    I need some help about adding items to JList. I work on some "library" kind of project. And I need to add readers to already existing JList. But when I try to add it, JList just resets, removes all the readers and starts adding readers to a new blank JList. But I don't need it to make new list but add it to the already existing one. I know it's something about creating new model after adding, but i don't know where to fix it. panelHorni = new JPanel(); listModel = new DefaultListModel(); listCtenaru = new JList(listModel); FileInputStream fis = new FileInputStream("myjlist.bin"); ObjectInputStream ois = new ObjectInputStream(fis); listCtenaru = (JList)ois.readObject(); listScroll = new JScrollPane(); listScroll.add(listCtenaru); listCtenaru.setPreferredSize(new Dimension(350, 417)); listCtenaru.setBackground(new Color(238,238,238)); panelHorni.add(listCtenaru); listener public void actionPerformed(ActionEvent e) { String jmeno = pole1.getText(); String prijmeni = pole2.getText(); listModel.addElement(jmeno +" "+ prijmeni); listCtenaru.setModel(listModel); pole1.setText(""); pole2.setText(""); pole1.requestFocus();

    Read the article

  • What is the effect of final variable declaration in methods?

    - by Finbarr
    Classic example of a simple server: class ThreadPerTaskSocketServer { public static void main(String[] args) throws IOException { ServerSocket socket = new ServerSocket(80); while (true) { final Socket connection = socket.accept(); Runnable task = new Runnable() { public void run() { handleRequest(connection); } }; new Thread(task).start(); } } } Why should the Socket be declared as final? Is it because the new Thread that handles the request could refer back to the socket variable in the method and cause some sort of ConcurrentModificationException?

    Read the article

  • FileConnection Blackberry memory usage

    - by Dean
    Hello, I'm writing a blackberry application that reads ints and strings out of a database. This is my first time dealing with reading/writing on the blackberry, so forgive me if this is a dumb question. The database file I'm reading is only about 4kB I open the file with the following code fconn = (FileConnection) Connector.open("file_path_here", Connector.READ); if(fconn.exists()==false){fconn.close();return;} is = fconn.openDataInputStream(); while(!eof){ //etc... } is.close(); fconn.close(); The problem is, this code appears to be eating a LOT of memory. Using breakpoints and the "Memory Statistics" view, I determined the following: calling "Connector.open" creates 71 objects and changes "RAM Bytes in use" by 5376 calling "fconn.openDataInputStream();" increases RAM usage by a whopping 75920 Is this normal? Or am I doing something wrong? And how can I fix this? 75MB of RAM is a LOT of memory to waste on a handheld device, especially when the file I'm reading is only 4kB and I haven't even begun reading any data! How is this even possible?

    Read the article

  • JNI AttachCurrentThread NULLs the jenv

    - by Damg
    Hello all, I'm currently in the process of adding JNI functionality into a legacy delphi app. In a single-threaded environment everything works fine, but as soon as I move into multi-threaded environment, things start to become hairy. My problem is that calling JavaVM^.AttachCurrentThread( JavaVM, @JEnv, nil ); returns 0, but puts the JEnv pointer to nil. I have no idea why jvm.dll should return a NULL pointer. Is there anything I am missing? Thank you in advance -- damg PS: * Environment: WinXP + JDK 1.6 * Using JNI.pas from http://www.pacifier.com/~mmead/jni/delphi/

    Read the article

  • How to display image in Swing? in textarea?

    - by Nitesh Panchal
    Hello, I am creating a chat application using JApplet. I have a TextArea where all chat messages go. Everything in working fine and smooth just as you would expect a basic chat application to do. Now i want to add support for gestures. I wanted to know, how can we show an icon in textarea? it only takes string in append() method. Thanks in advance :)

    Read the article

  • Buffering db inserts in multithreaded program

    - by Winter
    I have a system which breaks a large taks into small tasks using about 30 threads as a time. As each individual thread finishes it persists its calculated results to the database. What I want to achieve is to have each thread pass its results to a new persisance class that will perform a type of double buffering and data persistance while running in its own thread. For example, after 100 threads have moved their data to the buffer the persistance class then the persistance class swaps the buffers and persists all 100 entries to the database. This would allow utilization of prepared statements and thus cut way down on the I/O between the program and the database. Is there a pattern or good example of this type of multithreading double buffering?

    Read the article

  • JarEntry.getSize() is returning -1 when the jar files is opened as InputStream from URL

    - by Reshma Donthireddy
    I am trying to read file from the JarInputStream and the size of file is returning -1. I am accessing Jar file from the URL as a inputStream. URLConnection con = url.openConnection(); JarInputStream jis = new JarInputStream(con.getInputStream()); JarEntry je = null; while ((je = jis.getNextJarEntry()) != null) { htSizes.put(je.getName(), new Integer((int) je.getSize())); if (je.isDirectory()) { continue; } int size = (int) je.getSize(); // -1 means unknown size. if (size == -1) { size = ((Integer) htSizes.get(je.getName())).intValue(); } byte[] b = new byte[(int) size]; int rb = 0; int chunk = 0; while (((int) size - rb) > 0) { chunk = jis.read(b, rb, (int) size - rb); if (chunk == -1) { break; } rb += chunk; } // add to internal resource hashtable htJarContents.put(je.getName(), baos.toByteArray()); }

    Read the article

  • Does <T> need to be imported as a class for this to work?

    - by zxc
    In order for this to work, do you have to have an import statement for the T class? private static <T> void invertOrdering(List<T> list) { for (int i = 0; i < list.size() / 2; i++) { int j = list.size() - 1 - i; T item1 = list.get(i); T item2 = list.get(j); list.set(i, item2); list.set(j, item1); } }

    Read the article

  • Prevent duplicate entries in arraylist

    - by timyh
    Say I create some object class like so public class thing { private String name; private Integer num; public oDetails (String a, Integer b) { name = a; num = b; } ...gets/ sets/ etc Now I want to create an arraylist to hold a number of this object class like so. ArrayList<thing> myList = new ArrayList<thing>; thing first = new thing("Star Wars", 3); thing second = new thing("Star Wars", 1); myList.add(first); myList.add(second); I would like to include some sort of logic so that in this case...when we try and add object "second" rather than add a new object to the arrayList, we add second.getNum() to first.getNum(). So if you were to iterate through the ArrayList it would be "Star Wars", 4 I am having trouble coming up with an elegant way of handling this. And as the arraylist grows, searching through it to determine if there are duplicate name items becomes cumbersome. Can anyone provide some guidance on this?

    Read the article

  • Does close ever throw an IOException?

    - by TofuBeer
    After providing some answers here, and reading some comments, it would seem that, in practice IOException is never thrown on close for file I/O. Are there any cases in which calling close on a Stream/Reader/Writer actually throws an IOException? If an exception is actually thrown, how should it be dealt with?

    Read the article

  • Why Hibernates ignores the name attribute of the @Column annotation?

    - by svachon
    Using Hibernate 3.3.1 and Hibernate Annotations 3.4, the database is DB2/400 V6R1, running that on WebSphere 7.0.0.9 I have the following class @Entity public class Ciinvhd implements Serializable { @Id private String ihinse; @Id @Column(name="IHINV#") private BigDecimal ihinv; .... } For reasons I can't figure, Hibernate ignores the specified column name and uses 'ihinv' to generate the SQL: select ciinvhd0_.ihinse as ihinse13_, ciinvhd0_.ihinv as ihinv13_, ... Which of course gives me the following error: Column IHINV not in table CIINVHD Did anyone had this problem before? I have other entities that are very alike in the way that they are using # in their database field names and that are part of the PK and I don't have this problem with them.

    Read the article

  • ant conditions problem

    - by senzacionale
    I have problem with ant. I woul dlike to use conditions in ant. But i get error of: BUILD FAILED C:\Projekti\Projekt ANT\build.xml:412: Problem: failed to create task or type Cause: The name is undefined. Action: Check the spelling. Action: Check that any custom tasks/types have been declared. Action: Check that any / declarations have taken place. and this is code: <target name="test"> <input message="Write some text: " addproperty="foo" /> <if> <equals arg1="${foo}" arg2="bar" /> <then> <echo message="The value of property foo is 'bar'" /> </then> <elseif> <equals arg1="${foo}" arg2="foo" /> <then> <echo message="The value of property foo is 'foo'" /> </then> </elseif> <else> <echo message="The value of property foo is not 'foo' or 'bar'" /> </else> </if> </target>

    Read the article

  • Proper structure for dependency injection (using Guice)

    - by David B.
    I would like some suggestions and feedback on the best way to structure dependency injection for a system with the structure described below. I'm using Guice and thus would prefer solutions centered around it's annotation-based declarations, not XML-heavy Spring-style configuration. Consider a set of similar objects, Ball, Box, and Tube, each dependent on a Logger, supplied via the constructor. (This might not be important, but all four classes happen to be singletons --- of the application, not Gang-of-Four, variety.) A ToyChest class is responsible for creating and managing the three shape objects. ToyChest itself is not dependent on Logger, aside from creating the shape objects which are. The ToyChest class is instantiated as an application singleton in a Main class. I'm confused about the best way to construct the shapes in ToyChest. I either (1) need access to a Guice Injector instance already attached to a Module binding Logger to an implementation or (2) need to create a new Injector attached to the right Module. (1) is accomplished by adding an @Inject Injector injectorfield to ToyChest, but this feels weird because ToyChest doesn't actually have any direct dependencies --- only those of the children it instantiates. For (2), I'm not sure how to pass in the appropriate Module. Am I on the right track? Is there a better way to structure this? The answers to this question mention passing in a Provider instead of using the Injector directly, but I'm not sure how that is supposed to work. EDIT: Perhaps a more simple question is: when using Guice, where is the proper place to construct the shapes objects? ToyChest will do some configuration with them, but I suppose they could be constructed elsewhere. ToyChest (as the container managing them), and not Main, just seems to me like the appropriate place to construct them.

    Read the article

  • Is there a better way than a sequence of if's to handle events?

    - by Matt
    I recently ran across several objects implemented to handle events with a hard coded mapping using this pattern: public void handleEvent(Event event) { if(event.getCode() == SOME_STATIC_EVENT) doSomething(event); if(event.getCode() == ANOTHER_STATIC_EVENT) doSomethingElse(event); } where doSomething functions are implemented as methods of the same class. In hopes of striving for looser coupling, how would you suggest abstracting out this pattern? Also, what's the best approach for mapping 0..N functions to a fired event?

    Read the article

  • Dynamically add annotation to an existing class

    - by ng
    I have the following class public class Person { ... } I would like to create another class that would look like this. @SomeAnnotation public class Person { ... } Via a simple method like so. public static Class addAnnotation(Class originalType, Class<? extends Annotation> annotation) { // what goes here? } Is there an easy way to do this via ASM for example? What dependencies would I need. I have tried to Google this however the examples I have found are either incomplete or are doing something else. Other frameworks such as javassist would be just as good.

    Read the article

  • List of dependency jar files in Maven

    - by Sindri Traustason
    Using Maven 2, is there a way I can list out the jar dependencies as just the file names? mvn dependency:build-classpath can list the jar files, but that will include the full path to their location in my local repository. What I need is essentially just a list of the file names (or the file names that the copy-dependencies goal copied). So the list I need would be something like activation-1.1.jar,antlr-2.7.6.jar,aopalliance-1.0.jar etc... ideally as a maven property, but I guess, a file such as build-classpath can generate will do. What I am trying to achieve is writing a Bundle-ClassPath to an otherwise manually maintained MANIFEST.MF file for a OSGi bundle. (You shouldn't need to understand this bit to answer the question.) To clarify: The question is not about how to write manifest headers into the MANIFEST.MF file in a jar (that is easily googleble). I am asking about how to get the data I want to write, namely the list shown above.

    Read the article

  • Triggering Quartz job from JSF (Any front end)- How to wait for the job execution to be over

    - by Maximus
    I am developing a front end to trigger a quartz job on the fly. I have a form in the JSF page whose click action will dynamically trigger a quartz job. The job is invoked by the following statement, the job is triggered and everything works fine. scheduler.triggerJob("Job1",Scheduler.DEFAULT_GROUP,jobDataMap); From what I understand the job seems to run in a separate thread and the execution of the calling function does not wait for the job to be over. Since I am invoking the job from front end, I would like to wait till the job is over before I navigate to a different JSF page. So I can display an error message if the job fails. I would also like to display a message to the user, "Processing job, please wait.." until the job is actually over. Any ideas on how to accomplish this will be appreciated. Thanks !

    Read the article

  • Is there a design pattern to cut down on code duplication when subclassing Activities in Android?

    - by Daniel Lew
    I've got a common task that I do with some Activities - downloading data then displaying it. I've got the downloading part down pat; it is, of course, a little tricky due to the possibility of the user changing the orientation or cancelling the Activity before the download is complete, but the code is there. There is enough code handling these cases such that I don't want to have to copy/paste it to each Activity I have, so I thought to create an abstract subclass Activity itself such that it handles a single background download which then launches a method which fills the page with data. This all works. The issue is that, due to single inheritance, I am forced to recreate the exact same class for any other type of Activity - for example, I use Activity, ListActivity and MapActivity. To use the same technique for all three requires three duplicate classes, except each extends a different Activity. Is there a design pattern that can cut down on the code duplication? As it stands, I have saved much duplication already, but it pains me to see the exact same code in three classes just so that they each subclass a different type of Activity.

    Read the article

< Previous Page | 968 969 970 971 972 973 974 975 976 977 978 979  | Next Page >