java-programmer >>poster or wallpaper

poster or wallpaper

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- 5
  - Does anyone know where I can get the source code to the utility JAR itself ?Or, failing that, JAVA source code to *A* JAR utility ?
    (I can deal with it being written in java)
- 6
  - Override prepareRenderer()I've gathered that in order to change the background color of a row,
    one can either use the tablecellrenderer or can override the
    prepareRenderer() method. I have chosen to override the
    prepareRenderer() method. My question (and a reather silly one) is
    exactly how to call this method to then color your rows.
    
    I already have a jtable with is autogenerated by netbeans and all of
    the code I've seen, the jtable is created programmatically.
    
    Here is what I TRIED to do (any help is greatly appreciated):
    
    public void updateGUI(String newValue){
    DefaultTableModel errorTableModel = (DefaultTableModel)
    parentScreen.jTableErrors.getModel();
    int numRows = errorTableModel.getRowCount();
    numRows++;
    errorTableModel.setRowCount(numRows);
    parentScreen.jTableErrors.setModel(errorTableModel);
    Object newObjectError = (Object) newValue;
    parentScreen.jTableErrors.setValueAt(newObjectError, numRows - 1, 0);
    
    JTable coloredTable = new JTable( errorTableModel )
    {
    public Component prepareRenderer(
    TableCellRenderer renderer, int row, int column)
    {
    Component c = super.prepareRenderer(renderer, row, column);
    
    String message = (String) getValueAt(row, column);
    String[] dividedMsg = message.split(":");
    if(dividedMsg[0].equals("Error: ")){
    this.setBackground(Color.RED);
    }
    else{
    this.setBackground(Color.YELLOW);
    }
    
    return c;
    }
    };
    
    parentScreen.jTableErrors = coloredTable;
    
    }
- 9
  - writing email attachment file to diskI'm trying to capture an email attachment and write it to disk.
    I've coded the following lines in my attempt. The program seems
    to run and creates the local file alex99.pdf. However, when I
    tried to open it, it says it's corrupted and/or wasn't properly
    decoded. Any ideas?
    
    Properties props = new Properties();
    Session session = Session.getDefaultInstance(props, null);
    Store store = session.getStore("pop3");
    store.connect(host, username, password);
    Folder folder = store.getFolder("inbox");
    folder.open(Folder.READ_ONLY);
    Message message[] = folder.getMessages();
    for (int i = 0, n = message.length; i < n; i++) {
    System.out.println(i + ": " + message[i].getFrom() + "\t"
    + message[i].getSubject());
    Object obj = message[i].getContent();
    if (obj instanceof String) {
    System.out.println(">>>plain text");
    } else if (obj instanceof Multipart) {
    System.out.println("Multipart");
    Multipart mp = (Multipart) obj;
    System.out.println("mp count = " + mp.getCount());
    for (int j = 0, nn = mp.getCount(); j < nn; j++) {
    Part part = mp.getBodyPart(j);
    String disposition = part.getDisposition();
    if ((disposition != null)&& ((disposition.equals(Part.ATTACHMENT) ||
    (disposition.equals(Part.INLINE))))) {
    System.out.println("attachment");
    FileOutputStream fos = new FileOutputStream("alex99.pdf");
    part.writeTo(fos);
    } else if (disposition==null) {
    MimeBodyPart mbp = (MimeBodyPart)part;
    if (mbp.isMimeType("text/plain")) {
    System.out.println("text/plain");
    } else {
    System.out.println("other mime type");
    }................................
- 10
  - Q: Possible to auto-fallback back to MS JVM from Sun JVM ?Hi all.
    
    Ok, so it's no secret, MS can no longer distribute its Java VM with
    its OS'.
    
    Naturally, that didn't stop me from installing an old one so
    WindowsUpdate would see it and upgrade it to the last (MS) build:
    5.00.3810
    
    I also installed the latest SUN Java VM (1.4.2_03)
    
    *** Flash ***
    
    Woaaaah!! Just saw their "Law & Order" game
    (http://java.com/en/index.jsp)
    Gotta try that!
    
    *** End Flash ***
    
    So what I want in fact, is to use SUN's VM as default, but to
    automatically switch back to MS' VM for those sites that still use it
    (for example, my bank still uses it, so I can't issue payments if Sun
    is default -- annoying).
    
    Of course, this can be done manually in "Set Program Access and
    Defaults" in hte Window scontrol panel, but you have to select one or
    the other.
    
    Same with Sun's Java Plug-in control panel (Advanced tab).
    
    So... is there a way to perform an auto-fall-back to MS JVM when an
    applet cannot load/initialise with the Sun JVM ?
    
    Or create a list of site which must use MS instead of Sun?
    
    Any help appreciated.
    
    M.T.
- 12
  - Animation ProblemLew wrote:
    > James Sarjeant wrote:
    >> Thank you so much everyone, it worked with the javax.swing.Timer events.
    >> Still got other bugs to iron out but thats a huge hurdle overcome.
    >> Thanks again
    >
    > Remember: you think you have gotten away from the advice about the EDT,
    > but you haven't.
    >
    
    It's a pesky thing isn't it :-).
    
    --
    
    Knute Johnson
    email s/nospam/knute/
- 13
  - Choosing elements to display in a JSP using StrutsHello,
    
    I am very new to everything web development, so please bear with me.
    
    My development environment is:
    
    Win2k
    Tomcat 4.0.30
    Apache 2.0.48
    mod_jk/2.0.4
    j2sdk 1.4.2
    Struts 1.1
    mysql 4.0.18
    
    I am using Struts to develop my webapp in an MVC fashion. I am using
    forms based authentication to a mysql database.
    
    Using the tools in my development environment, I am wondering if it is
    possible to choose the elements displayed in a JSP based on the group
    the user is in (and still stay withing the MVC framework), or if that
    is even the right approach. I prefer to not show options to users if
    they do not have permissions to perform them.
    
    Any suggestions or advice would be great. If you know of any
    tutorials/books/web resources that you could point me to, that would
    be fantastic as well.
    
    Thanks in advance.
    
    Randy
- 13
  - Changing log level at runtimeYou know the situation: logging output is useless .. until you need it.
    
    Is there a way to configure log4j in a web application or an EJB with
    log level ERROR and have it change to DEBUG whenever an error happens?
    
    The only thing I can imagine is having a special servlet that you have
    to call with the browser to have it trigger a log level change for the
    whole web application.
    
    Are there better ways? Maybe with the jdk built-in logger?
    
    Or with log4j JMX? But I could not find any docs or examples.
    
    Thx,
    Juergen
- 14
  - hide NullPointerExceptionI have a GUI which throws a nullpointerexception when things go wrong.
    Then it closes. That nullpointerexception is expected and I want it
    ignored since before that it has already informed the user that
    something has gone wrong and its closing. How can I do this? If I just
    put the part of the function throwing the exception within try/catch,
    it tends to hang. If I leave it as is, it throws the exception but
    closes fine. I just don't want the user to see that exception.
- 14
  - Newbie question - reading delimited files and printing...Reading files - pipe delimited or comma delimeted...
    Searching for a element in one field and then showing certain fields where
    element is in line.
    
    eg...
    HEHE|HI|ME|2.5
    JOKE|HELLO|YOU|3.4
    DONT|HI|YOU|3.4
    
    I want all rows with YOU in second column and I want to print out 2nd and
    4th columns.
    
    SO, my answer would be
    HI 2.5
    HI 3.4
    ...
    
    Next question...
    same list only a datestamp on the end...
    HEHE|HI|ME|2.5|20031223091234
    JOKE|HELLO|YOU|3.4|20031223091245
    DONT|HI|YOU|3.4|20031223091247
    ....
    
    1) I want all rows with YOU in second column and I want to print out 2nd and
    4th columns in the 09:00:00 - 09:59:59 time frame.
    2) I want an average of response time(4th field).
    3) I want an average of response time broken down by hour.
    
    Can someone help with all of this?
    
    Please email to my home email (feel free to copy here).
    
    email***@***.com
    take out the _no_spam_
    
    Thanks,
    
    Markis
- 15
  - drag and drop in a JMenu/JMenuItem
    Can someone please point me to some sample code that allows drag and
    drop in a JMenu/JMenuItem. I know that Java doesn't support dnd in
    the menu stuff, but I need it anyway. Technically speaking it doesn't
    have to be a popup menu, but would be nice, as long as it has the look
    and feel of a popup menu (i.e. fonts, size, etc.). An example of what
    I'm talking about, via menus, is the start menu under Windows. Those
    menus allow you to do dnd, but of course it's Windows and they allow
    anything and everything. Just to note I'm using JDK 1.5.x if that
    helps for the code direction.
- 15
  - Hot-deployment of EAR/JAR files using classloaders (on JBoss app server)Hi,
    I am trying the following scenario:
    
    - I deploy an app.ear into the jboss server.
    - app.ear invokes a session bean deployed separately (sessionbean.jar)
    - everything works fine
    - I modify sessionbean.jar
    - I redeploy it without restarting the server (hot deployment)
    
    When app.ear invokes the sessionbean, it refers to the previous instance of
    the sessionbean. And because I have replaced it, it does not find the
    class...
    
    Then I read on, and I find that if you write custom class loaders, you can
    load new versions of classes on the fly (dynamic loading).
    So I wrote a custom class loader, which works fine when I call a basic java
    library, but there does not seem to be a way of 'redeploying' this
    sessionbean.jar as a bean (you can't invoke it anymore with the home/remote
    interface)....
    
    Can someone help me here ? I am basically trying to redeploy beans without
    redeploying the app server and having them immediately rebind to whichever
    application needs to use them.
    
    Thanks
    
    Steph
- 16
  - hi friends.please helpI am trying t make a jTable Using Abstract TableModel. But my JTable
    doesnot appear on the frame.I have written two classes myTable and
    jTable2 .My code is given below:
    
    import javax.swing.*;
    import java.awt.*;
    
    public class myTable {
    public static void main(String args[]){
    JTable2 tbl2=new JTable2();
    JTable aTbl=new JTable(tbl2);
    aTbl.updateUI();
    aTbl.setVisible(true);
    JFrame frame=new JFrame("Jtable using AbstractTableModel");
    JPanel pan=new JPanel();
    JScrollPane scp=new JScrollPane();
    scp.add(aTbl);
    pan.add(scp);
    frame.getContentPane().add(pan);
    frame.setVisible(true);
    frame.pack();
    }
    
    }
    
    import javax.swing.*;
    import java.sql.*;
    import java.util.*;
    import javax.swing.table.*;
    
    public class JTable2 extends AbstractTableModel{
    Connection con;
    Statement stmt;
    ResultSet rs;
    int columns;
    Vector allRows;
    Vector row=new Vector();
    String [] columnNames={"ID_CODE","NAME","SECTION"};
    
    public JTable2(){
    // connect to database
    try{
    db_connect();
    getData();
    }catch(Exception ex){
    ex.printStackTrace();
    }
    
    }
    void db_connect() throws SQLException{
    try{
    Class.forName("oracle.jdbc.driver.OracleDriver");
    
    con=DriverManager.getConnection("jdbc:oracle:thin:@158.144.71.242:1521:dbadp","payroll","sush");
    System.out.println("Connected");
    }catch(Exception ex){
    ex.printStackTrace();
    }
    }
    void getData() throws SQLException {
    try{
    stmt=con.createStatement();
    rs=stmt.executeQuery("select idcode,id_name,sec_code from
    employee");
    ResultSetMetaData rsMetaData=rs.getMetaData();
    columns=rsMetaData.getColumnCount();
    allRows=new Vector();
    while(rs.next()){
    Vector newRow=new Vector();
    for(int i=1;i<=columns;i++){
    newRow.addElement(rs.getObject(i));
    }
    allRows.addElement(newRow);
    }
    
    }catch (Exception ex){
    ex.printStackTrace();
    }
    }
    public int getRowCount(){
    return allRows.size();
    }
    public int getColumnCount(){
    return columns;
    }
    public Object getValueAt(int aRow,int aColumn){
    row=(Vector) allRows.elementAt(aRow);
    return row.elementAt(aColumn);
    }
    public boolean isCellEditable(int row, int col){
    return false;
    }
    
    }
- 16
  - test please disregard (explanation below if you wish)I sent 2 messages, and my newserver told me that the date on them expired so
    they got deleted. They were important, and i am upset, so i am testing to
    see if this will get deleted too.....
- 16
  - reinventing the wheelhttp://www.ted.com/index.php/talks/view/id/162
    
    This is off topic, but Java folk will like find it amusing. It shows
    a Dutch invention to replace the wheel, various mechanical walking
    machines. It has a mechanical step counter, a sort of primitive finite
    state automaton..
    --
    Roedy Green Canadian Mind Products
    The Java Glossary
    http://mindprod.com
- 16
  - stupid genericsWhen I first heard about generics I was excited. A great idea finally
    available in Java. But the way they are implemented really makes no sense.
    Because of type erasure generics do nothing that 1.4 code didn't already do
    by using Object as "generic" class for all (sub)classes.
    
    And the problem with arrays of generic classes? Simply ridiculous. There
    is no sane reason why the following code (from a self-learning chess
    program I've been working on) should not work, and yet...
    
    ArrayList<Piece>[] board;
    board = new ArrayList<Piece>[8]; // error: cannot create a generic
    // array of ArrayList<Piece>
    board[0] = new ArrayList<Piece>();
    board[0].add(0, new Rook(false, 0, 8));
    
    where of course Rook is a subclass of Piece.
    
    I'm forced to use board = new ArrayList[8]; which of course gives an
    unchecked warning.
    
    They should just throw away the whole generics thing and replace it with a
    C++ like approach.

Author

Message

gezerpunta

Posted: 2004-10-18 14:33:00

Top

java-programmer, poster or wallpaper Hi all
I need posters or wallpapers which is about programming and computer
science, for hanging

thanks

Index ‹ java-programmer

Next
- 1
  - Java Thread,Hi,
    
    I am spawing a new Thread in my application, which runs as an
    background process. I am looking to set -Xmx512mb memory to this new
    Thread programatically. How do i do it.
    thanks
- 2
  - Eclipse HTTP PluginLooking for an eclipse plugin (with source code preferibly) that will
    allow me to post an HTTP request. I am trying to integrate3 the IDE
    with a proprietary Server side app and want to be able to pass a large
    string as a parameter to a JSP page.
    Any help is greatly appreciated.
    
    Jason
- 3
  - synchronize vs gateI have a singleton in a web service that provides a collection and
    self-updates it on a periodic basis:
    
    doSelfUpdate()
    
    create temporary collection (time consuming)
    syncronize
    update temporary collection from current collection (fast)
    create temporary reference 'old' to current collection
    point current collection reference to temporary collection
    end syncronize
    do stuff with 'old' collection (time consuming)
    done
    
    getCollection()
    synchronize
    just waiting on monitor
    end synchronize
    return collection
    done
    
    It seems to me each thread accessing the getCollection method must
    wait on the monitor every time it is accessed -- which is not what I
    want. I just want to open and close the gate for a few milliseconds
    while the self-update is being done. What do y'all think about
    something like this:
    
    boolean isBusy=false;
    
    doSelfUpdate()
    create temporary collection
    isBusy=true;
    update temporary collection from current collection
    create temporary reference 'old' to current collection
    point current collection reference to temporary collection
    isBusy=false;
    do stuff with 'old' collection
    done
    
    getCollection()
    maxWait=10000
    waited=0
    while(isBusy && waited <maxWait) {
    waited+=500
    if(waited>=MaxWait) log error;
    wait 500
    }
    return collection
    done
    
    IMHO this means each thread consuming getCollection is a tiny bit
    slower because it has a condition that must be tested, but as a group
    they are not waiting in line for the monitor. Is this right?
- 4
  - Alternatives to Cobra for GUI<->Backend I/F ?Hi there
    
    Im working on an existing system which has a backend written in C/C++
    and we are using J2SE for the GUI forend. The backend end forend can
    be on different systems/platforms. Current we are using CORBA as the
    interface which works ok but it is tedious having to implement C++
    impl's and then also do the same in the java code. One of the problems
    is that we are continually adding new interfaces and modify existing
    ones. Its my impression that CORBA is more useful for more stable
    interfaces possibly between different vendors software.
    
    Are there any other technologies that it may be worth me looking into.
    It struck me that plain old CGI may be an alternative, and I've been
    told that SOAP maybe a way forward, there are probably others I don't
    know anything about and have never heard of. Any views on this matter
    would be great as Im a little out of touch because there are so many
    new technologies out there now days.
    
    Cheers
    
    Steve
- 5
  - [Struts] <set-property> how does it works?Hi all
    I know that in <action> mapping I can use a sub-tag <set-property
    property="" value="">
    How can I access to these information inside an action?!
    As I can imagine there should be a getProperty/getProperties method to the
    ActionMapping class ....but it isn't!!
    I appreciate any hint..
    
    thanx
    
    --
    ShadowMan
- 6
  - please explain this simple constructmy instructor likes to use this construct in class but never really
    explained why/how it works:
    
    while (true)
    {
    if (something) return; // break from while
    }
    
    can someone shed some light how this works?
- 7
  - Javascript problem - I don't know what to do about it?!?!Here is the script I have in my page :
    
    
    </script>
    
    It opens a new window when the user clicks on a certain link.
    
    Well, somewhere else in the page, I embeded a flash media object and
    found out now that everytime the page opens, the pop up window opens
    too which is NOT what I want. I want the Popup window to only open
    when the user clicks on a text link (which it did work perfectly until
    I put in the flash object).
    
    So why is the flash object calling the popup window instead of just
    playing like it is supposed to?
- 8
  - Problem with deploying war-files with jbossHello,
    
    our development-team has made a war-file.
    
    When I deploy this war-file in the right folder in jboss.
    
    ../server/default/deploy/..
    
    some file (in this case jpeg's) were't unzip/deploy in the temp-folder.
    
    Unzipping the war-file is showing that this files are there.
    
    What can I do to solve this problem?
    
    Any suggestion for an argument, when starting up the jboss or something else.
    
    Every help would be nice.
    
    Regards,
    Andreas
- 9
  - getDocumentBase and getCodeBase not recognized...Hi, Im having a slight problem.
    
    I am trying to load an image object with the code below, and I am NOT
    extending Applet in my class because I am working on an application.
    
    The problem is that getCodeBase AND getDocumentBase are not being
    recognized by my application, however I am sure that the required jars
    are in the build path... and that I've referenced them... most likely
    inapproprirately.
    
    My code is set up like this
    Base\
    Base\graphics\img.gifs.
    
    Code follows, I trimmed the imports mostly off, but the rest appear
    below the code...
    
    Thanks for your advice.
    
    import java.net.URL;
    import java.applet.Applet;
    
    ............
    String strImageUp = "graphics/up.gif";
    URL urlUp = getClass().getResource(strImageUp);
    Image imgUp = null;
    try {
    MediaTracker m = new MediaTracker(this);
    imgUp = getImage(getDocumentBase(), strImageUp);
    m.addImage(imgUp, 0);
    m.waitForAll();
    }
    catch (Exception e) {
    e.printStackTrace();
    }
    ................
    
    import javax.crypto.interfaces.PBEKey;
    import javax.imageio.*;
    import java.awt.image.*;
    import java.io.File;
    import java.io.IOException;
    import java.util.Vector;
    import java.awt.*;
    
    import javax.swing.*;
    import javax.swing.border.Border;
    
    import java.util.LinkedList;
    import java.util.ListIterator;
    import java.awt.event.ActionListener; //for buttons
    import java.awt.event.ActionEvent; //for button events
    import java.awt.event.KeyEvent; //for key shortcuts
    
    import java.math.*; //percentage rounding
- 10
  - page counter in JSP & JSTLHi everyone,
    
    I have a web application which consists of 2 JSP pages. Each page
    displays the number of time the page has been accessed. This is
    accomplished by using a jsp declaration :
    
    (this sample is taken from the following book : "Servlets and
    JavaServer Pages : The J2EE Technology Web Tier")
    
    <%! int pageCount = 0;
    void addCount() { pageCount++; }
    %>
    <html>
    <head>
    <title>page1.jsp</title>
    </head>
    <body>
    <% addCount(); %>
    This page has been visited <%= pageCount %> times.
    </body>
    </html>
    
    Now, let's say I want to ruse the JSTL tags instead. This will give
    something like (not tested) :
    
    <c:set var='pageCount1' scope='application' value='${pageCount1 +1}'/
    >
    This page has been visited <c:out var='pageCount1/>' times.
    
    I have 2 questions :
    
    Q#1 : with JSP declarations, the page counter can have the SAME name
    on each JSP. But if I use an application scoped counter, the counter
    will have to have a DIFFERENT name for each page (ie : pageCounter1
    for page1.jsp, pageCounter2 for page2.jsp). Is there a way to use the
    same name ?
    
    Q#2 : how do I initialize the value of the application scoped counter
    if I use JSTL ? (for example, what if I want the counter to start from
    100 ?)
    
    Thanks for helping !
- 11
  - Question about Database Connection PoolsHi Newsgroup,
    
    i have written an Objectpool for Database connections. All locked
    connections are stored within a Vector (called _used) and all unlocked
    connections are stored within a second Vector (called _unused).
    
    Now consider the following situation:
    
    ------------------- code ---------------------------------------
    DbConnectionPool pool = new DbConnectionPool( driver, url, user, passwd);
    Connection dbcon = pool.getConnection();
    
    int sizeUsed = pool.getUsed(); // returns 1, thats ok
    
    // ...
    // ... lets do some actions with dbcon ....
    // ...
    // ... programmer does not notice
    // ... that dbcon is still in use.
    // ... so he checks out a new connection
    //
    dbcon = pool.getConnection();
    
    sizeUsed = pool.getUsed(); // return 2, uppps!!!
    
    ------------------- code ---------------------------------------
    
    Because the programmer checks out a new connections, two database
    connections are now marked as _used.
    
    Is there any possibility to avoid such situations?
    
    Thank you in advance
    
    mike
- 12
  - How to simulate a busy taskHi everybody,
    
    I was trying to perform some tests in a multithreading application and
    I would like to simulate overloading. That is, I want to simulate
    threads performing a task that takes a certain time T. I have thought
    of the following possibilities:
    
    -Implement a method that sleeps during T milliseconds. Problem: this
    does not overload the computer, during those T milliseconds other
    agents can execute.
    
    -Implement a method that performs a busy wait (while(true){...}) and
    exits when T milliseconds have passed. Problem: there could be context
    switches in between, and so it could happen that another thread
    executes in the meantime (and that execution time should not count to
    decide when to terminate the busy wait).
    
    -Similar to the previous approach, but we try to count the milliseconds
    elapsed "by hand". That is, in every iteration we obtain the
    System.currentTimeMillis() and count as much as 1 millisecond (if it is
    really at least 1 millisecond greater than the value measured in the
    previous iteration). In this way, if the thread is interrupted while
    executing the method, nothing happens because we count at most 1
    millisecond per iteration. This does not work either too well, because
    more than 1 millisecond could have been elapsed between measures.
    
    So I'm not really sure if I can do this with some precision. If you
    have any suggestions, please let me know. Thanks in advance,
    
    S.
- 13
  - J2ME & EclipseI have just started playing with J2ME, using a software example I downloaded
    from http://www.garret.ru/~knizhnik/En_Home.htm#Shopper. I can successfully
    build the application and run it both in the emulator outside of eclipse
    using emulatorw, and also on my Nokia phone.
    
    I just can not run it within Eclipse, with or without debug. I get the
    following error message:
    
    Exception in thread "main" java.lang.UnsatisfiedLinkError:
    com.sun.midp.main.Configuration.getProperty0(Ljava/lang/String;)Ljava/lang/String;
    at com.sun.midp.main.Configuration.getProperty0(Native Method)
    at com.sun.midp.main.Configuration.getProperty(Configuration.java:32)
    at com.sun.midp.lcdui.Resource.<clinit>(Resource.java:30)
    at com.sun.midp.main.Main.initSystemLabels(Main.java:686)
    at com.sun.midp.main.Main.main(Main.java:103)
- 14
  - Problem starting out with Java . . .Hey. Im new to Java, and am having a prroblem with the netbeans IDE.
    every time i try to import java.awt.* , I can't use any of the
    methods(like they don't exist). I can compile it fine, but when I try to
    run it, I get "exception in class main".
    
    Can anyone help me, please?
- 15
  - Implementing an interface in eclipseUsing IntelliJ, I would be able to implement an interface whilst having
    it open in the editor. You could open the context window using the
    keyboard and choose to implement interface and magically the
    implementation appears complete with the statement "... implements
    SomeInterface"
    
    Does anyone know how to do the same in eclipse so I don't have to open
    that New Class window and manually choose the interface?