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- 2
  - OLAP & OLTP schemas and Java App ServerHi,
    
    (I hope this is the right group to post this. If not I apologize and
    would appreciate pointers.)
    
    We have a Websphere Applicaiton server for our application. We plan to
    have a database that is part relational and part star on DB2 UDB. We
    will need an OLAP tool and may use BRIO.
    
    Some questions on this approach:
    
    1. What is the best way to access the OLAP schema from Java (we plan
    to use hibernate but are concerned about its suitability for star
    schemas).
    Some things that I could think of are:
    - Use hibernate on the star schema (not sure if this is the best)
    - Create as many materialized views as necessary and use hibernate
    - Use java objects running on the DBs JVM (db optimized jvm implying
    better performance?)
    
    2. Is Brio the right tool to use for this scenario?
    I ask because we can't have direct integration with the J2EE
    applicaiton server (We have to give the user a different login page to
    brio to see the reports. But they may take hours to produce.)
    
    3. What are your experiences in combining star and relational tables
    in the same database?
    
    4. Any thoughts on using DB2 OLAP server? Apparently it has reporting
    capabilities and Java support, but unsure if it has any advantages
    over Brio.
    
    Thanks in advance,
    Naga
- 2
  - for wanids: very enticing tunes - gudri wonhe - (1/1)On Tue, 06 Sep 2005 23:52:20 +0200, bone wrote:
    
    > Hello all?
    Oh, ..you too?
    
    This sh*t is commonly known as SPAM. Stop it, before I
    have to send the boys around.
    
    --
    Andrew Thompson
    physci.org 1point1c.org javasaver.com lensescapes.com athompson.info
    "Who gave you the power? WE DID!!"
    Alice Cooper 'Department of Youth'
- 3
  - tridimensional view in B&WI made a program with java3d and I can print views from it.
    I want to print only the lines like the wireframe but without hide lines
    
    Have you same Ideas??
    
    zeno
- 4
  - Extract all dates from text documentHi,
    
    1) I have a bunch of documents, some of which may contain dates.
    2) For each document, I would like to identify all existing dates.
    3) The dates exist in multiple formats.
    Example: (May 5, 1932), (5,5,1932), (5/5/1932), (5-5-1942) etc.
    4) I would like to process a single document very quickly. In other
    words, i'm looking for a time efficient solution.
    
    Are there any existing parsers that take in a generic text string and
    return a collection of dates found in the text string?
    
    Are there any existing flex/cup files that perform this task?
    
    Thanks.
- 4
  - Printing using CUPS in Linux and Java 1.5According to the blurb one of the upgrades in 1.5 is the ability to
    print using CUPS in Linux. Does anyone have this working? I cannot get
    my Jva application to communicate with CUPS.
    
    Thanks,
    
    Alan
- 4
  - openGL java and X - server: a crashHy folks,
    I didn't know exactly where to post, in the end I decided for this
    forum, since we are talking about java, GL4java on linux environment.
    
    We are developing a java interface for the GIS GRASS
    (http://grass.itc.it) using GL4java calls for raster visualization.
    
    I'm not the developer that works on the GL part. On his computer
    everything compiles and works alright.
    
    When I run the application, when the first GL call comes (i assume
    so), the X server shuts down and restarts. In the /var/log/message the
    only line that defines what happened, is:
    kdm[2232]: Server for display :0 terminated unexpectedly
    Nothing else!
    
    I use Suse 9 (I upgraded from 8.2 hoping to solve that problem, but no
    way) which a Toshiba Satellite 5200-801 which loads an NVIDIA GeForce4
    460 Go.
    I downloaded and installed the drivers supplied by Nvidia and they
    work perfect for everything but this.
    
    I know NVIDIA to be unstable with linux nowadays, but I can't work
    this way!
    Has anyone encountered the same or similar problem?
    
    Regards,
    Andrea
- 6
  - applet is not initiallising.what's wrong with this source code.
    
    it is showing the message applet is not initiallising.
    --------------------------------------------------------------------------------------------------------------------------------------
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    
    public class LinearSearch extends JApplet implements ActionListener
    {
    JLabel enterLabel;
    JTextField enter;
    JTextArea outputArea1, outputArea2;
    JButton search;
    String output;
    int a[];
    
    public void init()
    {
    a=new int[Integer.parseInt(JOptionPane.showInputDialog("how many
    numbers, you want to input:"))];
    
    for(int i=0; i<a.length; ++i)
    a[i]=Integer.parseInt(JOptionPane.showInputDialog("enter the
    integer number."));
    
    output="numbers are:\n";
    for(int i=0; i<a.length; ++i)
    output += " "+a[i];
    
    for(int i=1; i<a.length; ++i)
    for(int j=0; j<=a.length-1; ++j)
    if(a[j]>a[j+1])
    {
    int t=a[j];
    a[j]=a[j+1];
    a[j+1]=t;
    }
    
    output += "\n\nnow numbers are in ascending order.\n";
    for(int i=0; i<a.length; ++i)
    output += " "+a[i];
    
    Container c=getContentPane();
    c.setLayout(new FlowLayout());
    
    outputArea1=new JTextArea();
    c.add(outputArea1);
    outputArea1.setText(output);
    
    enterLabel=new JLabel("enter the number, you want to search.");
    c.add(enterLabel);
    
    enter=new JTextField(10);
    enter.addActionListener(this);
    c.add(enter);
    
    outputArea2=new JTextArea();
    c.add(outputArea2);
    
    search=new JButton("new search");
    search.addActionListener(this);
    c.add(search);
    }
    
    public void actionPerformed(ActionEvent e)
    {
    if(e.getSource() == enter)
    {
    int subscript=linearSearch(a,
    Integer.parseInt(e.getActionCommand()));
    
    if(subscript != -1)
    outputArea2.setText("number found at position no. "+subscript+"
    in the sorted list.");
    
    else
    outputArea2.setText("Sorry!!! number not found. \n\nhave a look
    on new search");
    }
    
    else
    JOptionPane.showMessageDialog(null, "Please click on the Applet
    menu on the menu Bar.\n"+"click on the clone option.\n"+"Repeat the
    search process again.");
    }
    
    public int linearSearch(int b[], int k)
    {
    for(int i=0; i<b.length; ++i)
    if(b[i] == k)
    return i;
    
    return -1;
    }
    }
    
    ---------------------------------------------------------------------------------------------------------------------------------------
    it is asking for no. of elements. and input the numbers. but after then
    applet is not able to initialise.
- 7
  - Windows styleHI! I'm developing an application that is going tu run on windows XP
    Professinal, and I want that the buttons, combo boxes etc every
    component that I use, looks like a windows component, not like a swing
    button for example. I don`t know if anyone understands me.
    I'm using NetBeans IDE, (using jdk 1-4-2).
    
    When I am designing my form and I drag and drop a button for example,
    it has a rounded shape, like a normal windows button, but when I
    compile and run my project, the button is not rounded anymore, and
    doesn't looks like a Windows Button.
    What can I do??
    Thaks a lot!!
- 7
  - casting from int to byte problemit looks like I have a strange problem.
    I have a small class with several byte 'properties'
    
    and I put a values into them from int values casting them to byte..
    but for some values (like 143), casting result (with (byte)) is -113???
    it's the same with 147 casted to -109...
    and it should be a byte value (means, there should be no negative values)..
    
    value is lowered for 256
    why?
    
    did I missed something?
- 7
  - javadoc -linkoffline helpHowdy All!
    
    I am trying to issue a javadoc command with the following linkoffline
    option:
    -linkoffline http://java.sun.com/j2se/1.4.1/docs/api
    C:/java/j2sdk1.4.1_01/docs/api
    
    Both the file path and the url are valid, but I find the generated
    links are of the form:
    
    file:///E:/phd/semiInterface/doc/http://java.sun.com/j2se/1.4.1/docs/api/java/lang/reflect/Method.html
    
    Can anyone advise how I can make this work?
    
    Thanks for any help!
    
    Rob
    :)
- 9
  - Oracle JDBC and AppletHello
    I have an applet which download files to local computer from database
    (files are saved as BLOB fileds).
    Applet is signed bud when I want to get connection to Oracle (method
    getConnection from OracleDataSource) i have following error:
    
    java.security.AccessControlException: access denied
    (java.util.PropertyPermission oracle.jserver.version read)
    
    Applet working only when I running it from JBuilder. Otherwise the
    error comes.
    
    I can't see other posibility than using applets because number of
    files is very big. For example 20 000 to take at once, so the normal
    download method via http is not good here. Also the size of one
    download may be up to 1GB.
    
    Thanks for help
    
    Bartek
- 9
  - about static variableViv,
    
    Viv wrote:
    >I mean to say that the objects will get garbage collected but not the
    >static variables. Class will remain in memory till the JVM shutdown.
    >
    >Roedy wrote :
    >The only way you can recover the ram from a static class object is to
    >load it with a custom classloader, then drop even the reference to the
    >class loader.
    >
    >You can try what Roedy said.
    
    What means "recover the ram from a static class object"? What do you mean
    "recover"? I think there is not static class object -- only static class
    members.
    
    Do you know where can I find a sample dealing with how to write a customized
    ClassLoader with the functions as you mentioned?
    
    regards,
    George
    
    --
    Message posted via JavaKB.com
    http://www.javakb.com/Uwe/Forums.aspx/java-setup/200511/1
- 9
  - reading Mouse MOVE events without moving pointerHi,
    
    Does anyone know of way of setting up a java app so that a instead of
    mouse movements being used to update the pointer, the mouse move could
    be used to update, say, the viewport of a document?
    
    An example in more detail;
    what I want to do is use the mouse MOVE event that is caused by the
    movement of the mouse, but not update the pointer position (I would
    like the pointer to remain still or be invisble) but to allow me to
    update the viewport on a document. ie, user presses a 'trigger' key
    to put the code into a receptive mode, then all subsequent mouse
    movements (triggering mouse MOVE events) can be captured and used to
    update the viewport location- ie, mouse moves left, pointer remains
    still, viewport moves left.
    
    I don't know if this is possible due to the OS independance that java
    has. Maybe a solution involves the glass-pane in some (I am not
    familiar with the glass- yet. It is one of my avenues to search...)
    
    Thanks for any ideas... mucho thanks for any code examples....
    
    M.
- 15
  - How to Fail at Software DevelopmentHello,
    
    The book "How to Fail at Software Develoopment" is about all the
    strange and funny things people do in the name of developing software.
    I worked in software development for over 20 years and found silly
    things that were being done in the name of software development were
    being repeated again and again. As a matter of fact, most things that
    cause software projects to fail are forever being repeated. And you
    can spot the symptoms if you know what to look for.
    
    Most people running software projects don't have much software
    experience, so their inventions are usually not new. They rediscover
    the same mistakes over and over again. It turned out to be a book of
    very funny scenarios--some I lived through, and some were lived
    through by others.
    
    Those who don't know the history of software failure are doomed to
    repeat it. You can find the book on Amazon or wherever.
    
    Arthur Griffith
    "How to Fail at Software Development"
    http://www.anchorpointbooks.com
- 15
  - coordinating eventsHi there,
    
    I'm having difficulty trying to coordinate the sequence of events for
    populating a JTree with data received from a server app. I'm so-o-o-o close
    and yet no banana! It's proving to be very tricky processing. I could use
    some help in trying to make this work properly. Perhaps you may understand
    better as to why my efforts are being thwarted by the either the JTree
    object or its DefaultTreeModel?
    
    Here's the setup:
    
    1) I have a server app that, when requested from the client app, will
    provide a child count on any given directory node on the server. Also, it
    will serve up the names of each child node for any given node upon request.
    
    2) The client app contains a JTree object that I'm trying to initially
    populate with the root node. Subsequently, the plan is to dynamically
    populate any directory node in the JTree whenever the treeWillExpand( ... )
    event is triggered as the user tries to expand on a node.
    
    3) Throughout my code I have a number of System.out.println( ... )
    statements so that I can see what sequence of events are taking place as the
    client app makes requests to the server and receives replies back from the
    server. Also, some println(...) statements in some key methods which you'll
    see.
    
    4) The sequence of events is supposed to go like so:
    
    i) root node is created
    ii) as the root node is passed as a parameter when creating the JTree
    object
    the getChildCount( ) method of the root node [type DefaultTreeNode
    extends DefaultMutableTreeNode ]
    is called.
    
    public int getChildCount()
    {
    if (!hasChildren)
    {
    defineChildNodes();
    }
    return(super.getChildCount());
    }
    
    iii) Since the root node initially has no children, getChildCount( )
    then calls the method
    defineChildNodes( ).
    
    protected void defineChildNodes()
    {
    hasChildren = true;
    ref.requestChildCountFromServer(this);
    }
    
    As you can see, defineChildNodes( ) simply sets the flag
    hasChildren to true then
    calls a method requestChildCountFromServer(this) which exists in a
    class called Response
    referred here by the variable "ref". Also in the Response class
    there exists the method
    populateTree( ) which initially created the root node and JTree
    objects:
    
    protected void populateTree(String NodeName)
    {
    //System.out.println("Entering populatTree() method");
    //This could take a while, so change the cursor icon
    //ref.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
    try
    {
    String separator = "";
    if(ref.serverOS.equals("Windows"))
    separator = "\\";
    else
    separator = "/";
    rootNode = new DefaultTreeNode(NodeName, true, separator);
    expandingNode = rootNode;
    String rootPath = getLeadingPath(ref.rootPath);
    rootNode.setLeadingPath(rootPath);
    rootNode.setResponseReference(this);
    jTree1 = new JTree(rootNode);
    jTree1.setRootVisible(true);
    jTree1.setShowsRootHandles(true);
    jTree1.collapseRow(0);
    MouseListener popupListener = new PopupListener(ref);
    jTree1.addMouseListener(popupListener);
    
    //Listen to our own expand/collapse events to keep the labels in
    sync
    jTree1.addTreeWillExpandListener(this);
    
    }
    catch(Exception e){System.out.println("Exception in populateTree()
    method"); e.printStackTrace();return;}
    ....
    ....
    }
    
    iv) The requestChildCountFromServer( ) method then makes a request to
    the server app for
    the child count for the root node.
    
    v) I have a separate thread running that listens for all responses
    from the server
    called ResponseListener. In its run( ) method I have the
    following code:
    
    else if(connected == ref.ref.SENDING_CHILDCOUNT)
    {
    System.out.println("Received message: ReceivingChildCount");
    ref.expandingNode.numChildren = input.readInt();
    //expandingNode.setReceivedChildCount(true);
    ref.ref.imageLabel.setIcon(ref.ref.blank);
    ref.ref.textLabel.setText("");
    }
    
    When the root node was originally created I set a reference to it
    using a variable
    named expandingNode. Here you can see that the root node's
    instance variable
    named numChildren is set to a value read in by the DataInputStream
    object
    named input.
    
    vi) The requestChildCountFromServer( ) method in turn calls another
    method in the
    Response class named RequestChildrenFromServer(String path).
    RequestChildrenFromServer(String path) method requests from the
    server the names
    of all the child nodes for the root node.
    
    vii) ResponseListener then receives a response from the server:
    
    else if(connected == ref.ref.SENDING_TREE_DATA)
    {
    System.out.println("Received message: SendingTreeData");
    ref.expandingNode.TreeDataIncoming = true;
    ref.expandingNode.ReceiveChildrenFromServer(input);
    ref.ref.imageLabel.setIcon(ref.ref.blank);
    ref.ref.textLabel.setText("");
    }
    
    Here you can see that the root nodes method named
    ReceiveChildrenFromServer(input) is then called
    while passing it a reference to the DataInputStream so that the
    method can
    read in the names of the child nodes as they come in over the
    wire.
    
    viii) The root node's method ReceiveChildrenFromServer(input) then
    begins receiving the
    names of each child node, creates a new DefaultTreeNode object
    for each child node
    and adds it to the root node, seen below:
    
    protected void ReceiveChildrenFromServer(DataInputStream input)
    {
    System.out.println("Entering ReceiveChildrenFromServer()");
    
    DefaultTreeNode child = null;
    String name = "";
    try
    {
    
    //ref.ref.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
    //System.out.println("numChildren = " + numChildren);
    int nodeType = 0;//default
    //iterate through each of the children as they come in
    //from the server.
    for(int i = 0; i < numChildren; i++)
    {
    name = input.readUTF(); //get the name
    System.out.println("child node: " + name);
    child = new DefaultTreeNode(name); //create a new
    child node
    
    //determine if this node is a directory
    //or a file. Empty directories are denoted
    //as having (nodeType == -1)
    nodeType = input.readInt();
    //System.out.println("node type: " + nodeType);
    if(nodeType == 0)
    {
    //Since a file is a leaf node
    //we won't be needing to continue
    //reading in nodes for it.
    child.setResponseReference(ref);
    child.setAllowsChildren(false);
    child.setHasChildren(false);
    child.setLeadingPath(getWholeServerPath());
    if(ref.ref.serverOS.equals("Windows"))
    child.setSeparator("\\");
    else
    child.setSeparator("/");
    }
    else if(nodeType == -1)
    {
    child.setResponseReference(ref);
    child.setAllowsChildren(true); //It's an empty
    directory
    child.setHasChildren(false);
    child.setLeadingPath(getWholeServerPath());
    if(ref.ref.serverOS.equals("Windows"))
    child.setSeparator("\\");
    else
    child.setSeparator("/");
    
    }
    else
    {
    child.setResponseReference(ref);
    child.setAllowsChildren(true); //It's a directory
    with child nodes
    child.setHasChildren(true);
    child.setLeadingPath(getWholeServerPath());
    if(ref.ref.serverOS.equals("Windows"))
    child.setSeparator("\\");
    else
    child.setSeparator("/");
    }
    
    this.insert(child,i);
    }//end for loop
    
    //ref.ref.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
    }//end try
    catch(IOException ioe){ioe.printStackTrace();}
    catch(NullPointerException npe){npe.printStackTrace();}
    }//end method
    
    IT IS HERE THAT I RUN INTO PROBLEMS!!!!
    
    All the code you see compiles fine. What I found annoying is that, at
    run-time, the sequence of events were as I depict them here until I start
    reading in the names of the childnodes with the
    ReceiveChildrenFromServer(...) method. While it is going through its for
    loop, mysteriously the method getChildCount( ) is called again, which in
    turn calls defineChildNodes( ), which in turn calls
    requestChildCountFromServer(...), which interrupts the processing of the for
    loop in ReceiveChildrenFromServer(...) . Here is the read out from the
    console to prove it:
    
    ***************************************
    Entering requestChildCountFromServer
    waiting for response...
    checking...
    Received message: ReceivingChildCount
    checking...
    got ChildCount: 26 <<<Root node has 26 child nodes
    Entering RequestChildrenFromServer()
    path is: C:\JavaProjects
    Finished calling server for children
    Received message: SendingTreeData
    Entering ReceiveChildrenFromServer()
    checking for tree data ...
    child node: AssignmentServer <<<<ReceiveChildrenFromServer(...)
    method begins reading in names
    child node: AssignmentSubmitter
    child node: Borland
    child node: ClientServerJTreeProject
    child node: DBJavaBean
    child node: DirAdmin.bak
    Entering requestChildCountFromServer <<<This method is called by
    defineChildNodes( ) which was
    
    called by getChildCount( )
    waiting for response...
    checking...
    checking...
    Node Expanding.
    checking...
    checking...
    got ChildCount: 0 <<< Don't know
    why this is reading zero. It should be 26
    child node: DirectoryAdministratorProject <<<For loop from
    ReceiveChildrenFromServer(...) method
    
    resumes reading in names
    child node: EZSmtp
    child node: Icon Editor
    child node: images
    child node: IniFileProject
    child node: J2exe
    child node: JCalculator
    child node: JGridProject
    child node: JSlideShow
    child node: MSSTextEditorProject
    child node: MySQL_JDBC
    child node: PersonalNetSearchProject
    child node: Print_Preview
    child node: PropertiesFileAccessExample
    child node: Sample_EBusiness
    child node: SharewareProject
    child node: SystemTreeProject
    child node: TestProgram
    child node: Thread_Pooling
    child node: ZeroG
    Received message: ReceivingChildCount
    *****************************************
    
    Ultimately, I wind up with a root node being displayed in the JTree that
    only has maybe five or six child nodes displayed when there should be 26
    child nodes.
    
    For further clarity here are the methods requestChildCountFromServer(...)
    and RequestChildrenFromServer(...):
    
    public void requestChildCountFromServer(DefaultTreeNode node)
    {
    
    System.out.println("Entering requestChildCountFromServer");
    String name = "";
    try
    {
    //ref.ref.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
    
    output.writeInt(ref.PATH);
    output.flush();
    output.writeUTF(node.getWholeServerPath());
    output.flush();
    output.writeInt(ref.REQUEST_CHILD_COUNT);
    output.flush();
    System.out.println("waiting for response...");
    timer1 = new ChildCountTimer(node);
    timer1.start();
    timer1.join();
    System.out.println("got ChildCount: " + node.numChildren);
    if(node.numChildren > 0)
    {
    //NodeExpanding = false; //reset
    RequestChildrenFromServer(node.getWholeServerPath());
    //Set up TreeDataTimer so that we know we have a
    //response from the server.
    timer2 = new TreeDataTimer(node);
    timer2.start();
    timer2.join();
    }
    
    //ref.ref.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
    }
    catch(InterruptedException ie){}
    catch(IOException ioe){ioe.printStackTrace();}
    catch(NullPointerException npe){npe.printStackTrace();}
    }
    
    protected void RequestChildrenFromServer(String path)
    {
    System.out.println("Entering RequestChildrenFromServer()");
    
    //Request Children from server
    try
    {
    //ref.ref.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
    output.writeInt(ref.PATH);
    output.flush();
    System.out.println("path is: " + path);
    output.writeUTF(path);
    output.flush();
    //Sending REQUEST_CHILDREN should cause a response
    //from the server: SENDING_TREE_DATA
    output.writeInt(ref.REQUEST_CHILDREN);
    output.flush();
    
    //ref.ref.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
    
    }
    catch(IOException ioe){ioe.printStackTrace();}
    System.out.println("Finished calling server for children");
    }
    
    I realize this post is rather lengthy, however, I didn't know how else to
    explain my dilemma with this project. If you need more information, just
    ask.
    
    Please advise,
    
    Alan

Author

Message

Edsoncv

Posted: 2007-3-3 2:49:00

Top

java-programmer, JNI Question On Mar 2, 2:17 pm, Gordon Beaton <email***@***.com> wrote:
> On 2 Mar 2007 08:05:22 -0800, Edsoncv wrote:
>
> > If I have only the C part, I would cast the "native1" object, pass
> > to "setup" and cast back the object, but since the setup function is
> > called from java, I don't know how to access native1 object from
> > "setup". Is it possible?
>
> Of course.
>
> Either store it someplace in the native code where it's visible to
> both methods (i.e. not as a local variable in solve() like your
> example).
>
> Or, remembering that even native methods have return values, return it
> to the caller (cast to jlong) so that it can be passed back to the
> next method, where you cast it back to the appropriate pointer type
> before attempting to use it.
>
> /gordon
>
> --
> [ don't email me support questions or followups ]
> g o r d o n + n e w s @ b a l d e r 1 3 . s e

Thanks Gordon, I think I'll pick the second option.

Edsoncv

Posted: 2007-3-3 2:49:00

Top

java-programmer >> JNI Question On Mar 2, 2:17 pm, Gordon Beaton <email***@***.com> wrote:
> On 2 Mar 2007 08:05:22 -0800, Edsoncv wrote:
>
> > If I have only the C part, I would cast the "native1" object, pass
> > to "setup" and cast back the object, but since the setup function is
> > called from java, I don't know how to access native1 object from
> > "setup". Is it possible?
>
> Of course.
>
> Either store it someplace in the native code where it's visible to
> both methods (i.e. not as a local variable in solve() like your
> example).
>
> Or, remembering that even native methods have return values, return it
> to the caller (cast to jlong) so that it can be passed back to the
> next method, where you cast it back to the appropriate pointer type
> before attempting to use it.
>
> /gordon
>
> --
> [ don't email me support questions or followups ]
> g o r d o n + n e w s @ b a l d e r 1 3 . s e

Thanks Gordon, I think I'll pick the second option.

Index ‹ java-programmer

Next
- 1
  - Things That People Buy .Hi Antonio ,
    Of Sun's press release , You scratch out :
    " Makes me not want to buy a new PC just yet . "
    
    Oh God ... Don't hold your breath .
    
    While Sun produces these fantastical press releases ,
    Asians are actually shipping things that people buy .
- 2
  - RSA ciphered streams problemHi. I've got a problem with the RSA ciphered streams. Here is a piece of
    code that generates an exception :
    
    KeyPairGenerator gen = KeyPairGenerator.getInstance("RSA");
    System.out.print("Generating the RSA key pair...");
    KeyPair kp = gen.generateKeyPair();
    System.out.println("done.");
    Cipher ci = Cipher.getInstance("RSA");
    ci.init(Cipher.ENCRYPT_MODE,kp.getPublic());
    Cipher cid = Cipher.getInstance("RSA");
    cid.init(Cipher.DECRYPT_MODE,kp.getPrivate());
    CipherOutputStream cout = new CipherOutputStream(new
    FileOutputStream("rsa.dat"),ci);
    ObjectOutputStream oout = new ObjectOutputStream(cout);
    oout.writeObject(kp.getPrivate().toString());
    oout.flush();
    oout.close();
    CipherInputStream cin = new CipherInputStream(new
    FileInputStream("rsa.dat"),cid);
    ObjectInputStream oin = new ObjectInputStream(cin); // Exception here
    System.out.println(oin.readObject());
    oin.close();
    
    The exception is EOFException and it's not very weird because the file
    "rsa.dat" is empty after writing to it!! It happens only if object is "big"
    ( when I try to write some short String, for example, everything's ok ).
    When I tried to write an unciphered output ( without using
    CipheredOutputStream ) it went well of course.
    My question is : can anybody tell me why it happens? What should I do to
    write "big" objects to ciphered output stream using ObjectOutputStream
    properly?
    Thanks for any requests.
    
    Kuba
- 3
  - How to listen out for a stream of data coming from (web)serverHello
    
    I have an applet that connects to a server (same location as web server) and
    connects to a server on a socket. This all works fine for sending commands
    to this server. But the server can send data to the client at any moment in
    time. So how do I listen out for the activity? do I launch a separate thread
    that sits listening for incoming data?
    
    What is the way to do it?
    
    Angus
- 4
  - Sun's OpenJDK in Debian?Hi,
    
    I'm surprised that this wasn't discussed already in the past on this list
    (or in the BTS of some important java packages), but what is the status
    of Sun's Java architecture in Debian?
    
    It is licensed under GPL2 and should be compatible with DFSG.
    
    As far as I know only a few components are not yet freely available,
    especially all which are subject to the Assembly Exception
    (http://openjdk.java.net/legal/exception-modules-2007-05-08.html,
    http://www.sun.com/software/opensource/java/faq.jsp).
    
    Is this the main blocker for accepting OpenJDK in Debian? Would it be
    possible to just omit the binary modules or to replace these with free
    implementations from other free projects?
    
    Please CC: me.
    
    Jens
    
    --
    To UNSUBSCRIBE, email to email***@***.com
    with a subject of "unsubscribe". Trouble? Contact email***@***.com
- 5
  - JMF, FrameAccess, sound, faster processingI used JMF's example class FrameAccess to process audio/video files. The
    Processor processes data according to the frame rate specified in the file.
    
    1. Is there a way to do this processing faster? I don't want to view (and listen
    to) those vids, just process them. I'm ready to use 100% of the CPU if need be.
    
    2. As the file is processed, a sound is generated and can be listened to through
    a sound card's output. Is this entirely necessary? I'm asking because I want to
    process files simultaneously and that would result in a cacophony. Besides, say
    I want to listen to my own music while the processing takes place.
    
    3. How does one extract sound from a video file? Can it be extracted as a whole?
    Can it be broken down into chunks according to extracted image frames? How? In
    which formats? I'm stuck in an implementation of Codec interface, much like
    JMF's example PreProcessCodec.java, but with AudioFormat (supported ins and
    outs), so I can access a sound frame through a Buffer, but I don't know how to
    proceed.
    
    Thanks for any insight.
- 6
  - Passing large C buffers to Java (via JNI) without copying?I'm trying to determine whether this is even possible... I have a
    _very_ large buffer malloc'd on my C heap that I would like to hand
    over to Java, preferably as a Byte[]. So far, every example of this
    that I have come across involves _copying_ the data from my C buffer
    into java storage. Is there any way to avoid this expensive (very
    expensive in my case) operation?
- 7
  - Question regarding Java's OOP implementation.According to Wikipedia, one of the core concepts of OOP is
    Encapsulation; being defined as follows: "ensuring that users of an
    object cannot change the internal state of the object in unexpected
    ways; only the object's own internal methods are allowed to access its
    state. Each object exposes an interface that specifies how other
    objects may interact with it. Other objects will rely exclusively on
    the object's external interface to interact with it." Not that I
    regard Wikipedia's definition of OOP as the leading authority, it just
    happens to be handy and provides a definition that fits my own ideas.
    On to the question; If I create a class called AClass and inside
    declare a class level variable with the private modifier and some other
    methods, e.g.
    
    public class AClass {
    
    private int number;
    
    public AClass(int num) {
    number = num;
    }
    
    public void setAnotherAClass(AClass anotherAClass, int num) {
    anotherAClass.number = num;
    }
    
    public int getAnotherAClass(AClass anotherAClass) {
    return anotherAClass.number;
    }
    
    public void display() {
    System.out.println("Number: " + number);
    }
    }
    
    And a class to test AClass:
    
    public class Test {
    
    public static void main(String[] args) {
    
    AClass one = new AClass(1);
    AClass two = new AClass(2);
    
    one.display();
    two.display();
    
    one.setAnotherAClass(two, 3);
    two.display();
    }
    }
    I would expect the compiler first to complain that number has private
    access in AClass... Barring that I'm not sure what I'd expect it to
    complain about, but something doesn't seem right. Child classes
    derived from AClass were not able to make changes to objects of type
    AClass which is what I would expect. But because one and two are
    distinct objects the fact that they belong to the same class shouldn't
    mean they can change each other's private instance variables. I
    wasn't able to find anything directly relating to the question in an
    hour or so of Googling. I also read through Java's tutorials on OOP to
    see if they had anything specific to say, which they did not.
    
    Thank you for your time and ideas.
    
    Carl Summers
- 8
  - commons-logging: runtime change of propertiesHi,
    
    I try to use commons-logging with the logs methods of J2SE 1.4.2 to
    generalize the logging in my appl.
    
    Doesn't exists a method to upload the defaul file properties of J2SE
    at run time and not usig the -D option at startup?
    
    Exists e method to change the propeties of the logger at runtime? for
    example the output file path...
    
    Thanks Cristian
- 9
  - [Update] FreeQueryBuilder 2005.05FreeQueryBuilder.2005.05
    http://querybuilder.sourceforge.net
    
    FreeQueryBuilder is a GUI SQL client written in 100% Java.
    You can create SQL queries without directly writing SQL.
    Works with any JDBC compliant database, including
    ORACLE, MySQL, HSQLDB, Firebird, SQLServer.
    
    This release includes FreeReportBuilder, a visual report designer.
- 10
  - \n troublesOK, again I have troubles dealing with String. I have a field of the type
    String which contains some text that is separated into lines at random
    places, or in other words, the text contains \n\r (or \n in the case of
    linux). I write this field into a file and there it looks ok, but when I
    read it back I get the whole string in one line. So I figured I'd add a
    separator at the end of each line. However, then I get an empty line after
    each line! I'm using GZIP to pack the data, so perhaps that is causing this?
    Btw. after each block of text I write an end-of-block string to know that
    it's the end of that block.
    Here's the explanation in code:
    
    String notes = ""; // the result
    String lin = ""; // used to read one line from the file
    final String eob = "---$#-||-"; // end of block
    lin = filein.readLine(); // I'm reading the 1st line
    
    while (lin.compareTo(eob) != 0) {
    notes += lin + System.getProperty("line.separator");
    lin = filein.readLine();
    if (lin == null) { break; } // this will never occur, but just in case
    }
    return notes;
    
    //-------------
    // filein is a BufferedReader
    // I can't change that, don't ask why, and
    // because of that this is how I read a file
    filein = new BufferedReader(
    new InputStreamReader(
    new BufferedInputStream(
    new GZIPInputStream(
    new FileInputStream("testFile.gz"))))));
    
    I figured I could erase one empty line after the reading-in is done, but I'm
    not sure if this will happen in every case, on every computer. I'm thinking
    it could be an anomaly for Windows files.
    Anyway, I'm waiting for some suggestions ;)
    
    Gajo
- 11
  - Action or Subclass method?I need to know which is the PROPER way of handling this situation:
    
    I would like to be able to cascade all the JInternalFrames in a
    JDesktopPane.
    
    Should I create a
    
    1) cascade() method in a subclass of JDesktopPane? or
    
    2) create a CascadeAction (a subclass of AbstractAction) and pass a
    reference of the JDesktopPane?
    
    Both ways work. HOWEVER, which is the PROPER Object Oriented solution?
- 12
  - Putting certificates in ldapI have openldap running, and I was able to put java objects there like
    so:
    
    Integer i = new Integer( 28420 );
    ctx.bind( "cn=myRandomInt", i );
    
    Suppose I already have the cert inside java.security.cert.Certificate
    . What would be the correct syntax to add this cert with ctx.bind ? Do
    I need to explicitly add this userCertificate;binary to slapd.conf? My
    schema is:
    
    database ldbm
    #suffix "dc=my-domain,dc=com"
    suffix "o=certStore"
    #rootdn "cn=Manager,dc=my-domain,dc=com"
    rootdn "cn=certManager,o=certStore"
    # Cleartext passwords, especially for the rootdn, should
    # be avoid. See slappasswd(8) and slapd.conf(5) for details.
    # Use of strong authentication encouraged.
    rootpw secret
    # The database directory MUST exist prior to running slapd AND
    # should only be accessible by the slapd/tools. Mode 700 recommended.
    directory /var/lib/ldap_magna
    schemacheck off
    # Indices to maintain
    index objectClass eq
    
    Please help,
    iksrazal
- 13
  - Opening Image files with IE as default always ( using Browser Launcher)Hi,
    I have downloaded some image files by connecting to a URL and I am
    trying open that image file using BrowserLauncher.
    I am using windows xp and the default one to open image files is
    windows picture and Fax Viewer.
    I could not see the image in Internet Explorer when I am trying to
    open the image files. But when I set in the properties of image files
    from "windows picture and Fax Viewer" to "Open with internet
    Explorer", I could see the image.
    
    Some trasfer details..
    File Type : .jpg
    HTTP/1.0 200 Ok
    MIME-version: 1.0
    Content-Length: 297362
    Content-type: application/jpg
    
    I tried to change in http headers , but could not succeed in opening
    the image.
    can anybody suggest me that,
    I change the properties of the image file ( or http headers) such that
    it should be open with internet explorer by default,after the image
    downloaded.
    
    Any suggestions or help is appreciated.
    
    Regards,
    Hari.
- 14
  - Date problem"Simon" <email***@***.com> wrote in message
    news:email***@***.com...
    > Ingo R. Homann wrote:
    >> You could design a programming language whose array-indices start with
    >> -3, that would make as much sense.
    >
    > So you want array-indices to start with 1? I don't see the analogy.
    
    It's the princple of least surprise. When you design something, you want
    to surprise your users as little as possible. To me, it's quite surprising
    that 5 refers to June and not May, for example. For array-indices, starting
    at 1 or 0 is okay (both makes sense), but -3 or 42 or anything else would be
    quite surprising as well.
    
    - Oliver
- 15
  - Loop != LoopStephen Riehm schreef:
    >
    > don't those two loops have different semantics, ie: the scope of myvalue?
    > My understanding would be that myvalue in the first loop would be
    > overwritten 9 times and then the last value would be available to code
    > appearing after the loop. The myvalue in the second loop basically has
    > no effect because it falls out of scope (and into the garbage
    > collector's hands) as soon as you leave the loop.
    >
    
    Oh, it was just a quick example, there supposed to be done something
    with myvalue later in the loop. The point was, myvalue is only needed
    inside the loop and not outsite.
    
    int myvalue=0;
    for (int i=0;i<10;i++) {
    myvalue=calculate(i);
    .. do something with myvalue
    }
    .. myvalue no longer needed
    
    for (int i=0;i<10;i++) {
    int myvalue=calculate(i);
    .. do something with myvalue
    }
    ..my value not needed anymore
    
    I believe this example is somewhere on the web too, but I forgot where
    (probably javasoft.com or javaworld.com).