java-programmer >>Sinottico

Sinottico

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- 3
  - Problem with JNI on LinuxI am having a problem getting JNI to work on Linux. I think it is with
    how I am creating the shared object file. I am using Java 1.5.0_8 and
    Redhat Enterprise version 3 release 4. I have not used JNI before so I
    did a web search and found a simple example that I am trying to get to
    work. The problem is that I am getting an UnsatisfiedLinkError. It looks
    like there are many flavors of this error and I can get at least three
    of them :(
    
    My Java program is:
    
    class FirstJNI
    {
    public native void displayHelloWorld();
    public native void displayOther();
    public native String getLine(String prompt);
    
    static {
    System.out.println("in static");
    System.loadLibrary("FirstJNI");
    }
    
    public static void main(String[] args)
    {
    System.out.println("entered main");
    System.out.println("creating new FirstJNI");
    FirstJNI jN=new FirstJNI();
    jN.displayHelloWorld();
    jN.displayOther();
    
    String input = jN.getLine("Enter Some Thing ");
    System.out.println("You Entered " + input);
    }
    }
    
    and my c library is:
    
    #include "FirstJNI.h"
    #include <stdio.h>
    
    JNIEXPORT void JNICALL
    Java_FirstJNI_displayHelloWorld(JNIEnv *env, jobject obj)
    {
    printf("Hello world! \n");
    return;
    }
    
    JNIEXPORT void JNICALL
    Java_FirstJNI_displayOther(JNIEnv *env, jobject obj)
    {
    printf("Hello world! This is Other Function.\n");
    }
    
    JNIEXPORT jstring JNICALL
    Java_FirstJNI_getLine(JNIEnv *env, jobject obj, jstring enter)
    {
    char buf[128];
    const char *str = (*env)->GetStringUTFChars(env, enter, 0);
    printf("%s", str);
    (*env)->ReleaseStringUTFChars(env, enter, str);
    
    scanf("%s", buf);
    return (*env)->NewStringUTF(env, buf);
    }
    
    I am building them with the following commands:
    
    /usr/java/jdk1.5.0_08/bin/javac FirstJNI.java
    /usr/java/jdk1.5.0_08/bin/javah -jni FirstJNI
    gcc -O2 -I/usr/java/jdk1.5.0_08/include
    -I/usr/java/jdk1.5.0_08/include/linux -fno-strict-aliasing -fPIC
    -fno-omit-frame-pointer -W -Wall -Wno-unused -Wno-parentheses -c FirstJNI.c
    gcc -Wl,-soname=libFirstJNI.so -shared-libgcc -lc -shared -o
    libFirstJNI.so FirstJNI.o
    
    If I then try and run it (after setting my LD_LIBRARY_PATH) I get:
    
    [hsr@palain8 jni]$ /usr/java/jdk1.5.0_08/bin/java FirstJNI
    in static
    Exception in thread "main" java.lang.UnsatisfiedLinkError:
    /users/hsr/apache-tomcat-4.1.32/webapps/perf/jni/libFirstJNI.so:
    /users/hsr/apache-tomcat-4.1.32/webapps/perf/jni/libFirstJNI.so: cannot
    open shared object file: No such file or directory
    at java.lang.ClassLoader$NativeLibrary.load(Native Method)
    at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1751)
    at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1676)
    at java.lang.Runtime.loadLibrary0(Runtime.java:822)
    at java.lang.System.loadLibrary(System.java:993)
    at FirstJNI.<clinit>(FirstJNI.java:9)
    
    This is strange since it is giving me a fully qualified path and if I do
    an ls of that path the file is there. So, just for fun I removed the
    file, tried again and got:
    
    [hsr@palain8 jni]$ /usr/java/jdk1.5.0_08/bin/java FirstJNI
    in static
    Exception in thread "main" java.lang.UnsatisfiedLinkError: no FirstJNI
    in java.library.path
    at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1682)
    at java.lang.Runtime.loadLibrary0(Runtime.java:822)
    at java.lang.System.loadLibrary(System.java:993)
    at FirstJNI.<clinit>(FirstJNI.java:9)
    
    This indicates to me that in the first example it really knew the file
    was there and that there was something else wrong. Next I went to the
    demo directory of the java 1.5.0_8 install and grabbed an .so file out
    of there and copied t to my directory. Now I get:
    
    [hsr@palain8 jni]$ /usr/java/jdk1.5.0_08/bin/java FirstJNI
    in static
    entered main
    creating new FirstJNI
    Exception in thread "main" java.lang.UnsatisfiedLinkError: displayHelloWorld
    at FirstJNI.displayHelloWorld(Native Method)
    at FirstJNI.main(FirstJNI.java:20)
    
    This is exactly what I would expect and the fact that this time it found
    the .so indicates to me that it has nothing to do with my misnaming the
    methods. So, I can only conclude that it is seeing my .so but not
    recognizing it as valid which indicates that I am not linking it correctly.
    
    After this long winded posting does anyone have any words of wisdom or
    suggestions?
    
    Thanks
    
    Howard
- 3
  - M'I`5'Persecu tion ' how an d w hy di d it s tart?-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
    -= how and why did it start?. -=
    -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
    
    The harassment didn't. start by itself, so someone must have been there at
    the outset to give it a firm push and set the. "animals" after me. It looks
    as if I was set up in June 1990, and the timing indicates. someone from
    university was. responsible.
    
    >One thing which has. been missing from this discussion is this simple
    >prognosis: that. maybe he is right and that, despite his admitted
    >mental condition, there really is a campaign against him. organised by
    >now-influential ex-students. of his university.
    
    In May or June 1990, Alan Freeman. on Radio 1 read out a letter from someone
    who had known me for a few years, who wrote of the. one who "wore out his
    welcome with random precision" (from the Pink. Floyd song). Freeman went on
    to say to the writer "that's a hell of a. letter you wrote there". The
    indication is strongly. that people I had parted from soon before nursed a
    grudge against me and were trying. to cause trouble for me.
    
    The suggestion is that Freeman might have shown the. letter to other people,
    and things. could have snowballed from there. Right from the start the real
    source (security services. presumed) didn't announce themselves as the
    origin, but let the. "talkers", the radio DJs, believe that they were the
    originators.. Think about it; if you announce, "we're MI5 and we have a
    campaign against. this bloke" then people might not go along with it; but if
    you say, "everyone. else is getting at this bloke because he 'deserves' it"
    then people will join in with. fewer qualms.
    
    >Why would "they" wish to assassinate. your character?
    
    It's the. classic case of hitting a cripple to prove you're stronger. Why
    would the security services expend hundreds of thousands of. pounds and more
    than six years of. manpower to try to kill a British citizen? Because they
    are motivated by people who knew. me at university and feel personal
    animosity; because they. knew me to be emotionally weak, and it is in the
    nature of bullies to prey on those. known to be weak; and because they can
    rely on the complicity of the establishment, which the security. services
    manipulate and derive funding. from. This is England's biggest humiliation
    today, and the British security services. are intent on preventing their
    humiliation becoming reality. by continuing their campaign of attempted
    murder to suppress. the truth from becoming public.
    
    1032
- 3
  - OSes people bitch about vs. OSes people don't useThomas G. Marshall wrote:
    > JTK coughed up:
    >
    > ...[rip]...
    >
    >
    >
    >>Yes. XP just doesn't go down friend.
    >
    >
    > So you'd call me a liar if I said it has BSOD'd on me several times?
    >
    
    Nope. I'd call you a liar if you tried to claim that your experience,
    which differs from that of 99.44% of the rest of the SP2-using
    population, is somehow indicative of serious and fundamental problems
    with XPSP2.
    
    >
    >
    >>All you "H8rs" better sharpen
    >>up and take a good hard look at why Linux continues to be an also-ran,
    >>because your last-grasp "Windows crashes when the sun goes behind a
    >>cloud, Linux never has even once!" delusion is becoming laughable.
    >
    >
    > I'm not a linux junkie, I much prefer PC's even though my origin is in the
    > unix arena 20+ years ago. Once I can tame a pc with cygwin and other
    > helpers, then I'm much happier in an environment that has so many more
    > titles written for it.
    >
    
    You and me both friend. So if'n a guy has an XP box with Cygwin on it,
    tell me again how that is somehow "inferior" to a Linux box?
    
    > And even so, I will just have to admit that the linux boxes that I've seen
    > as firewall/nat's just run and run and run, and have so even when linux was
    > relatively young.
    >
    
    "firewall/nat's". Ok, assuming that's true, do you see the logical
    fallicy there? How many XPSP2 boxes do you see being used solely as a
    "firewall/nat"? Zero? Less than zero?
    
    >
    > (Thomas G. Marshall complaint regarding SP2 for XP goes here)
    >
    
    Yeah, whatever.
    
    >
    >>Hmm. Well, that makes one unsatisfied customer out of... what, a few
    >>billion?
    >
    >
    > Try smacking your head against a wall for a few times to realize what you
    > just said. If that doesn't work, then google for the population of the
    > planet. If so inclined, look up the estimate of how many PC's and in fact
    > PC's running xp there are. Then on top of that realize that you also don't
    > have a notion as to whom SP2 affects adversely, and then rephrase.
    
    Yeah I'll get right on that. While I'm busy not doing that, you get
    busy not realizing that Linux is a niche player, "why you just restart
    the window manager!" == crash, and the tired old "Linux never crashes!"
    saw is now about as meaningful as the "Linux is virus-proof!" saw.
- 3
  - User data persistenceI am writing a Java application that uses about 1000 parameters in
    various calculations. All these parameters are displayed to the user in
    a JTable, and any can be modified. I would like to persist the user
    changes to these parameters, on the local machine. I'm new to Java, and
    am considering what the best options are for data persistence. It seems
    to me that, in this case, there are too many values to consider saving
    them using java.util.prefs.Preferences, and distributing a database
    with the app is probably overkill.
    
    I have previously written something similar using Microsoft VB.NET,
    where I created an XML file with some initial data, and distributed it
    with the application. The XML file was read into a DataSet, which was
    bound to DataGrid. If the user changed any values in the grid, the
    underlying DataSet was updated, and the XML file re-written to disk. Is
    it possible to do something similar in Java? I have looked at the
    Connection and ResultSet interfaces, but it does not appear that they
    can be used to read and write XML files.
    
    Mike.
- 4
  - eclipseAndreas Kohn wrote:
    
    >Works for me on FreeBSD/i386 6.0-CURRENT. I applied attached build to
    >have eclipse build with mozilla-devel instead of the default mozilla.
    >
    >
    I've combined this fix with the one Bruno sent, as well as a few other
    random cleanups. Here's an updated package:
    
    http://www.varju.ca/alex/freebsd/eclipse-devel-3.1m6-3.tgz
    
    The libswt-mozilla library is building now, but I don't think it's
    working correctly on my system. I'm not positive, but I think the Help
    system uses it .. if I try to go to Help Contents, nothing happens.
    (This is better than before the plugin was built, as then it created a
    mozilla process that spun forever).
    
    This patch is still missing Motif support. I've just flagged this as
    broken, as I don't actually expect to track this down myself. My i386
    system is far too slow to do test builds on, and it doesn't like there
    are linux x86_64 motif build files to base an amd64 build on.
    
    >One strange thing: At one build stage, it looked like it would build
    >gtk64 support things, is this to be expected on i386?
    >
    >
    It's possible that I've messed something up there, but it's also
    possible that Eclipse builds more than it actually needs. What exactly
    are you seeing?
    
    Alex.
- 4
  - XML and J2EE 1.3Hello,
    I'd like to know wheather I can use a program that uses xml-modules
    out of J2SE 1.4 within J2EE 1.3?
    Are the XML-Modules of J2SE1.4 identical with the modules from J2EE
    1.3, at least to a some extent?
    Thank you very much, Raffael Vogler
- 7
  - JList Font BugConsider this SSCCE. If you take out the comment on the setFont
    statement, it stop working -- displaying a blank screen in W2K/JDK 1.0
    
    Why. It fails even when I set it to the default Dialog, 12 , BOLD.
    
    // sample use of jList
    // The code is quite different from AWT List.
    
    import java.awt.Color;
    import java.awt.Font;
    import javax.swing.event.ListSelectionEvent;
    import javax.swing.event.ListSelectionListener;
    import javax.swing.JFrame;
    import javax.swing.JList;
    import javax.swing.ListSelectionModel;
    
    public class TestJList
    {
    
    /**
    * Debugging harness for a Frame
    *
    * @param args command line arguments are ignored.
    */
    public static void main ( String args [] )
    {
    final JFrame frame = new JFrame();
    
    final JList flavour = new JList( new String[] { "strawberry",
    "chocolate", "vanilla"} );
    flavour.setForeground( Color.BLUE );
    flavour.setBackground( Color.WHITE );
    System.out.println( flavour.getFont() );
    
    // flavour.setFont( new Font( "Dialog", 12, Font.BOLD ));
    
    // setting the selection
    flavour.setSelectedIndex( 0 );
    flavour.setSelectedValue ( "chocolate", false /* scroll */ );
    
    // allowing multiple selections, the default.
    flavour.setSelectionMode(
    ListSelectionModel.MULTIPLE_INTERVAL_SELECTION );
    
    // set multiple selections
    flavour.setSelectedIndices( new int[] { 0, 2} );
    // there is no setSelectedValues method
    
    flavour.addListSelectionListener( new ListSelectionListener()
    {
    /**
    * Called whenever the
    value of the selection changes.
    * @param e the event that
    characterizes the change.
    */
    public void valueChanged(
    ListSelectionEvent e)
    {
    
    // detecting individual
    selection
    System.out.println(
    "--selection--" );
    
    // will be null if there
    are none or multiple selections.
    String choice = (String)
    flavour.getSelectedValue();
    System.out.println(
    choice );
    
    // will be -1 if there
    aare none or muliple selections.
    int which =
    flavour.getSelectedIndex();
    System.out.println(
    which );
    
    // detecting multiple
    selections
    System.out.println(
    "--multiples--" );
    
    Object[] choices =
    flavour.getSelectedValues();
    for ( Object aChoice :
    choices )
    {
    System.out.println(
    aChoice );
    }
    int[] indexes =
    flavour.getSelectedIndices();
    for ( int index :
    indexes )
    {
    System.out.println(
    index );
    }
    }
    });
    frame.add( flavour );
    
    frame.setSize( 100, 100 );
    frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
    frame.validate();
    frame.setVisible( true );
    } // end main
    
    }
    --
    Canadian Mind Products, Roedy Green.
    http://mindprod.com Java custom programming, consulting and coaching.
- 7
  - Forth versus C -- and JavaUlrich Hobelmann wrote:
    > Wolf Wejgaard wrote:
    > > I once wrote a short intro to Forth as a comparison with C. You
    > > find it at http://holonforth.com/holon/forthc.htm I wonder if it
    > > is useful.
    >
    > In power.htm you might want to point out at the end that because it
    uses
    > the stack, Forth can even return more than one return value, while C
    > can't. It is strange that a language can call a function with one
    > parameter, but can't call the return continuation with more than one.
    
    Forth, C, and Java/Lisp/Scheme are harmonious.
    
    Both the parameter stack and return stack are 'unframed' in native
    machine code or Forth. The parameter stack frame is 'framed' with C,
    however, the return stack framing is compiler implementation defined.
    With Java, Lisp and Scheme both the parameter stack and return stack
    are 'framed'.
    
    The framing causes the functional equivilant of a stack 'frame' pointer
    referencing and de-referencing for every lambda/function/subroutine.
    
    example of particular,
    FORTH $FFFE ;
    C *f();
    A JAVA example is not possible with Java, Lisp or Scheme without a
    direct native core machine code subroutine call ( and closure violation
    ( RPLCAR , maybe in Lisp/Scheme, depending upon compiler implementation
    ), acronym, RPLCAR, Replace Contents of Adress Register, or, maybe, a
    write to the A bus with Chuck Moore's new architectures, C18, 25X )
    
    maw
- 7
  - C++ to JVM compilerThere used to be an alpha quality JVM backend for RedHat's branch of
    GCC, but it was abandoned, because FOSS luminaries did not approve of
    Java (strange, because both are out to crush Microsoft)
    
    Now that Java is going open-source again, I hope this project will be
    resurrected. C++ and Java are the most widely used languages. It's a
    shame that C++ can not be compiled to JVM, even though there is a ton
    of platforms that it can be compiled to, and there is a ton of
    languages that do compile to JVM.
    
    Let me list the advantages:
    
    * definitively determine memory corruption caused by a C++ program
    (valgrind and VC++2005's debug mode help, but can not always detect
    it; also they are much slower than JVM; it would also be nice to be
    able to detect uninitialized memory access, but I don't think JVM can
    help with that, since it has everything initialized)
    
    * call C++ programs more easily from Java, presumably
    
    * run C++ on some exotic platforms with JVM and no C++ compiler (rare)
    
    * run some C++ code faster (Java sometimes beats C++ on numerics-heavy
    tests - currently rare, but things seem to be changing in favor of
    JIT)
    
    * run C++ safely - I know there are arrogant C++ coders who would
    claim that their C++ code can not be exploited, but is there an
    automated way to prove that?
    
    (This could make a great summer-of-code project, unless it's too hard
    - I don't actually know)
- 7
  - help! compilation error in javai am getting this error when i compile my java code
    
    Exception in thread "main" java.lang.NoClassDefFoundError:
    D:\STest\TestClient/java
    
    plzz tell me what to do.. i hv included all possible library files in the
    classpath..still the same error. plz tell me how resolve it..
- 8
  - RTF parser componentHi all.
    i want component which is sperating text frm rtf text.rtf text contains
    images and some embedded objects which i want to seperate.
    Does anyone know it.
    Please help me.
- 8
  - Treasure Trooper what you do here is you complete simple surveys and offers, some
    require a credit card, but i just do all the free ones :D
    
    its easy to do, you just register and do the offers, then click the
    "done" button when you have completed it to what the instructions say,
    here is the website if you want to check it out
    
    www.treasuretrooper.com/111524 (copy and paste into browser
    
    this is how the payment works: say in june you made 60$, then on the
    15th of next month, so on july 15th you would get your money. they send
    a check in the mail so yes, you have to provide your correct address,
    not a fake one (dont worry they dont spam you with shit) and you will
    get a check in the mail from them and you can cash it like any other
    check.
    
    so far, i have been doing this thing for 2 months and i have been payed
    $156.50 total. its easy money and only takes about half an hour a day
    if your really keen on it, but usually 10 minutes is fine. on their
    forums i ha ve heard that people are making like $200+ i hope i can get
    that much in the future. im pretty close.
    
    once again, if you are interested in signing up, here is where you go:
    www.treasuretrooper.com/111524 (copy and paste into your browser)
- 8
  - ibatis sqlMap, LIKE operatorI've been using iBatis sql maps in my J2EE application with great
    results so far, but I've come across a bit of a roadblock, and my usual
    savior, Google, hasn't been able to help me out of this one. The one
    hits that seems to be exactly what I am looking for seems to have
    vanished from the web:
    
    http://www.mail-archive.com/email***@***.com/msg00284.html
    
    I can't seem to get queries that use the LIKE operator to work.
    According to the sqlmap docs, this should work:
    
    SELECT * FROM PRODUCT WHERE PRD_DESCRIPTION LIKE '%dog%'
    OR
    SELECT * FROM PRODUCT WHERE PRD_DESCRIPTION LIKE #value#
    // description property == "%dog%"
    
    When I run the SQL against my MySql db, I get results. When I run the
    SQL using sqlMaps (substituting my String and the % operators for
    #value#), I get no results. Here is my SQL (with table/column names
    replaced):
    
    select count(*) myCount from table_t
    where field_f like '%45111q%'
    
    in my sqlmap XML file, I have this SQL:
    
    select count(*) myCount from table_t
    where field_f like #value#
    
    // (I know string appends waste mem)
    I am passing in a String like this: String s = "%" + someStr + "%"
    
    I have tried specifiying the parameterClass as java.lang.String as well
    as not specifying at all.
    
    I suspect the % sign is being escaped somehow, but cannot determine
    this. Both my logging and MySQLs loggnig just show ? in the statement.
    SqlMap logging shows this:
    
    PreparedStatementLogProxy - {pstm-100121} Parameters:
    [%h80111n6gb111c31o8zezojqdh111111%]
    
    Has anyone managed to use LIKE successfully? It would be a huge help to
    overcome this problem.
    
    Thanks,
    -BR
- 10
  - Need a second (mouse-) pointerHi!
    
    I need a second (mouse-) pointer in my swing-based application. I like
    to use it as a "ghost mouse pointer". It'll be controlled by the
    application and not by an other input device.
    
    So, do you know a way to do that trick?
    
    Much thanks in advance,
    Christian
- 14
  - DER decoding from x.509 v3 certificateI need to read the extension field of a x.509 v3 certificate.
    I use the java method getExtensionValue().
    The method return an array of bytes DER-encoded.
    I want to read it as a String and print it on screen. So I have to decode
    the array and convert it.
    I try a lot of way to do that but I never obtain good result.
    Someone can help me?
    Then, the DER encoding is equal to Base64 encoding or not?
    
    Thanks

Author

Message

sm.sm.sm.

Posted: 2005-12-10 22:16:00

Top

java-programmer, Sinottico Dovrei sviluppare un sinottico in java qualche idea non so da dove partire
Grazie

Mark Haase

Posted: 2005-12-11 5:16:00

Top

java-programmer >> Sinottico In article <439ae338$0$7318$email***@***.com>,
"sm.sm.sm." <a.a..a> wrote:

> Dovrei sviluppare un sinottico in java qualche idea non so da dove partire
> Grazie

non parlo italiano bene, pero penso che un libro sia una buon inizio. se
parli inglese, el sito web e' molto utile:

http://java.sun.com/j2se/reference/faqs/index.html

--
|\/| /| |2 |<
mehaase(at)gmail(dot)com

Roedy Green

Posted: 2005-12-11 5:34:00

Top

java-programmer >> Sinottico On Sat, 10 Dec 2005 15:16:20 +0100, "sm.sm.sm." <a.a..a> wrote, quoted
or indirectly quoted someone who said :

>Dovrei sviluppare un sinottico in java qualche idea non so da dove partire
>Grazie

I think that would translate as:

I would like to develop a synoptic application in Java. I don't have
a clue where to start.

Thanks.

You mean as in comparing Bible stories to make up excuses for the
differences?

vhttp://www.mindspring.com/~scarlson/synopt/

--
Canadian Mind Products, Roedy Green.
http://mindprod.com Java custom programming, consulting and coaching.

Index ‹ java-programmer

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- 1
  - Socializing site EXCLUSIVELY for TECHIESTechnopax.com, (http://www.technopax.com) the first socializing web
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    next to some text received from the server. I have looked everywhere I
    can think of for a similar piece of code, but I haven't succeeded yet.
    
    I use a TextArea for inserting the text received but I don't know how
    to insert the image into the TextArea next to the text. Is there any
    way to do this?
    I also want some of the text and the image to be hyperlinked to other
    web pages for loading upon cliking. I think I have found how to do
    this, although I haven't tried it yet.
    
    Any help specially with the first question will be appreciated.
    
    Thank you
    Miguel
- 4
  - basic question on Java in XPHello,
    
    can someone please tell me how to ascertain what version (if any) of Java is
    installed in a WinXP platform?
    
    my friend needs some kind of Java module installed so that she can do a
    tutorial for an online registration service.
    
    any help would be appreciated.
    
    Cynthia
- 5
  - Project confusionOkay I'm not exactly sure what I'm supposed to do. I know I should
    create a file that creates an abstract tree but I can't figure out
    exactly what the other programs do and how I should use them to
    implement an abstract tree. So if someone could please shed some light
    as to what direction I should be going in it would be a lot of help.
    The website as to where the assignment is located is as follows:
    http://www.cs.uiowa.edu/~slonnegr/plc/. The pdf that describes the
    homework is under the link Parse Homework under the Homework header.
    Agains thanks for the help.
- 6
  - How to download metafiles using a signed appletI want an applet which, once launched, downloads 3 metafiles (files
    that it will need later on to work properly) and proceeds into a
    processing phase only if the files have been successfully fetched.
    
    So far I do not have a solution for requesting these files and writing
    them locally.
    
    Am I following the right track with URL and HttpURLConnection, or
    should I be looking into packages like the Apache Jakarta project?
    
    Is there possibly a more straightforward way to instruct the JRE to go
    get file "http://www.foo.com/dist/localdata.dat" and put it at
    location "C:\localdata.dat" ?
    
    Is there possibly some correlation between the domain mentioned in my
    signing certificate and the domain from which I download any
    particular file?
    
    Thanks for any ideas,
    
    Brian Herbert Withun
- 7
  - How to use an unsigned number in Java?People, is there a library that allow me to use unsigned numbers? I need
    this to implement a protocol but I don't want to have to keep masking a
    long number.
- 8
  - XMPP Java bot loop questionI want to write a bot for XMPP (Jabber) in Java (1.6) using smack
    libraries (http://www.igniterealtime.org).
    
    I have already written a GUI client using smack, so I'm familiar with
    how it works.
    
    For the bot however, I'm in doubt about the main loop in combination
    with event listeners. The bot basically just sits idly (until explicitly
    stopped) listening for presence changes of contacts. The presence
    changes are dealt with by a roster listener.
    
    How would I wait for those events and have the application keep
    executing? I am a bit clueless aobut threads in Java, but I have used
    them in Delphi...
    
    On a side note, if anyone can shed light on how to use the commons
    daemon (http://commons.apache.org/daemon/), that would be useful later
    on.
    
    Many thanks in advance,
    --
    Sabine Dinis Blochberger
    
    Op3racional
    www.op3racional.eu
- 9
  - arrays of generic typesEclipse tells me that arrays of generic types are not legal, e.g.: it
    won't allow the following:
    
    QuadTree<MyNodeType> [] allQuadTrees;
    
    Anyone know why this is the case?
- 10
  - Reporting tool to be used with swingHello All,
    
    I'm looking for a report generation tool to be used in a swing project
    I'm working. The resports will involve very complex charts and graphs.
    Kindly suggest tools which will meet these requirements.
    
    Thanks and Regards
    
    Chanchal
- 11
  - public static final - compilation errorOn Tue, 28 Jun 2005 17:49:11 +0200, Kamil Roman wrote:
    
    > Hi,
    >
    > is it possible to initialize a public static final member of a class in
    > the class' constructor? I try to do this and I receive error message:
    >
    > variable PLUS is declared final; cannot be assigned.
    
    {... code ...]
    
    No, the static finals need to be initialized before that. Why don't you
    use a static initializer block (static { /* ... */ }), which would be
    called at class load, in which you can initialize your members.
    
    --
    You can't run away forever,
    But there's nothing wrong with getting a good head start.
    --- Jim Steinman, "Rock and Roll Dreams Come Through"
- 12
  - odd mouselistener issueHi Guys
    
    I'm probably doing something stupid... but:
    
    I've got a JFrame with borderlayout. In the centre box, I've got a
    JPanel. If I add a mouselistener to the jframe, it works fine (but
    I've got coords relative to the frame which is correct but not what I
    want - I want coords relative to the panel). However, when I add the
    mouselistener to the panel, I get no mouseevents being returned at all.
    
    Any ideas in what way I might be being stupid?
    
    TIA
    
    Peter.
- 13
  - GUI and command lineHello,
    
    I need to connect my GUI program with a terminal in Linux (command
    line). The task is to input inside a textField the command to exectue as
    for exemple: "ls -al" or "gcc whatever.c -o whatever" but everything
    must be done by a GUI program.
    
    How can I call the terminal or execute these commands?
    
    thanks,
    
    Marcelo
- 14
  - executeQuery() doesn't time out, blocks indefinitely on network failureI am developing an application that must gracefully recover from
    network failures, however I noticed that executeQuery() never returns
    or throws an exception for a time out when the network goes down (which
    I simulated by unplugging my ethernet cable). The TCP connections of
    all my pooled database connections remain open and dead even after
    plugging the cable back in. Calling queryTimeout() explicitly has no
    effect--executeQuery() stays blocked on network IO forever. Is there a
    way to time out executeQuery(), or some way to stop it from never
    returning?
    
    I'm using version 10.2.0.1.0 of Oracle's JDBC driver with the 1.5 JDK.
    
    Code:
    
    import java.util.*;
    import java.sql.*;
    import oracle.jdbc.pool.*;
    
    public class Oracle
    {
    private OracleDataSource oracleDataSource;
    
    public Oracle() throws Exception
    {
    oracleDataSource = new OracleDataSource();
    oracleDataSource.setURL("jdbc:oracle:oci:@dev");
    oracleDataSource.setUser("dbp");
    oracleDataSource.setPassword("dbp");
    oracleDataSource.setConnectionCachingEnabled(true);
    }
    
    public void validate()
    {
    Connection c = null;
    Statement s = null;
    ResultSet r = null;
    
    try
    {
    System.err.printf("connecting...\n");
    c = oracleDataSource.getConnection();
    System.err.printf("connected\n");
    s = c.createStatement();
    s.setQueryTimeout(1);
    
    for (;;) {
    System.err.printf("executing...\n");
    r = s.executeQuery("select 1 from dual");
    System.err.printf("executed\n");
    r.close();
    try { Thread.sleep(1000); } catch (Exception e)
    { }
    }
    }
    catch (Exception e)
    {
    e.printStackTrace();
    try { r.close(); } catch (Exception ee) { }
    try { s.close(); } catch (Exception ee) { }
    try { c.close(); } catch (Exception ee) { }
    }
    }
    
    public static void main(String[] args)
    {
    Oracle oracle = null;
    
    try
    {
    oracle = new Oracle();
    oracle.validate();
    }
    catch (Exception e)
    {
    e.printStackTrace();
    System.exit(1);
    }
    }
    }
    
    Output:
    > javac -cp ./ojdbc.jar Oracle.java && java -cp .:./ojdbc.jar Oracle
    connecting...
    connected
    executing...
    executed
    (ethernet cable unplugged...)
    executing...
    (i waited a very long time, and nothing happened...)
- 15
  - Java Newbie Question: Character Sets, Unicode, et al [Long]Roedy Green wrote:
    > Ve need some definitions that make clear the distinction between:
    > an character set,
    > a character
    > a glyph
    > a font
    > an encoding.
    
    I'll take a stab at it.
    
    I decided to see what Unicode had to say on the matter. That seemed
    relevant, but may have been a mistake. In any event, here are some
    possibly relevant defintions from the Unicode 4.0 glossary
    (http://www.unicode.org/glossary/):
    
    ==== From the Unicode 4.0 Glossary ====
    
    Abstract Character. A unit of information used for the organization,
    control, or representation of textual data. (See Definition D3 in
    Section 3.3, Characters and Coded Representations .)
    
    Character. (1) The smallest component of written language that has
    semantic value; refers to the abstract meaning and/or shape, rather than
    a specific shape (see also glyph), though in code tables some form of
    visual representation is essential for the reader's understanding. (2)
    Synonym for abstract character. (See Definition D3 in Section 3.3,
    Characters and Coded Representations .) (3) The basic unit of encoding
    for the Unicode character encoding. (4) The English name for the
    ideographic written elements of Chinese origin. (See ideograph (2).)
    
    Character Encoding Form. Mapping from a character set definition to the
    actual code units used to represent the data.
    
    Character Encoding Scheme. A character encoding form plus byte
    serialization. There are seven character encoding schemes in Unicode:
    UTF-8, UTF-16, UTF-16BE, UTF-16LE, UTF-32, UTF-32BE and UTF-32LE.
    
    Character Set. A collection of elements used to represent textual
    information.
    
    Coded Character Set. A character set in which each character is assigned
    a numeric code point. Frequently abbreviated as character set, charset,
    or code set.
    
    Code Point. (1) A numerical index (or position) in an encoding table
    used for encoding characters. (2) Synonym for Unicode scalar value.
    
    Code Unit. The minimal bit combination that can represent a unit of
    encoded text for processing or interchange. (See Definition D5 in
    Section 3.3, Characters and Coded Representations .)
    
    Encoded Character. An abstract character together with its associated
    Unicode scalar value (code point). By itself, an abstract character has
    no numerical value, but the process of "encoding a character" associates
    a particular Unicode scalar value with a particular abstract character,
    thereby resulting in an "encoded character."
    
    Encoding Form. (See character encoding form.)
    
    Encoding Scheme. (See character encoding scheme.)
    
    Font. A collection of glyphs used for the visual depiction of character
    data. A font is often associated with a set of parameters (for example,
    size, posture, weight, and serifness), which, when set to particular
    values, generate a collection of imagable glyphs.
    
    Glyph. (1) An abstract form that represents one or more glyph images.
    (2) A synonym for glyph image. In displaying Unicode character data, one
    or more glyphs may be selected to depict a particular character. These
    glyphs are selected by a rendering engine during composition and layout
    processing. (See also character.)
    
    Glyph Image. The actual, concrete image of a glyph representation having
    been rasterized or otherwise imaged onto some display surface.
    
    ==== End of Glossary Excerpt ====
    
    Note: the glossary does not contain a definition of "character
    encoding", but it seems to be used in the Unicode context as an
    abbreviation for "character encoding form" (_not_ "character encoding
    scheme").
    
    The Java documentation is a bit confused and inconsistent in its
    terminology with respect to characters, character sets, and character
    encodings. For instance "the Java platform uses Unicode as its native
    character encoding" (i18n docs), but at the same time UTF-8 and UTF-16
    are referred to as "character encodings" that all Java implementations
    must support. Elsewhere in the docs these are the names of "charsets",
    which is to say that in some places the docs call them "encodings" and
    in others "charsets." Moreover, in Java 1.4 there is now
    java.nio.charset.Charset, "A named mapping between sequences of
    sixteen-bit Unicode characters and sequences of bytes." This is
    consistent with MIME, but different from Unicode usage (which would call
    such a thing a "character encoding scheme", except that it also implies
    a certain collection of characters to which it can apply).
    
    RFC 2045 (MIME) says, in part:
    NOTE: The term "character set" was originally to describe such
    straightforward schemes as US-ASCII and ISO-8859-1 which have a
    simple one-to-one mapping from single octets to single characters.
    Multi-octet coded character sets and switching techniques make the
    situation more complex. For example, some communities use the term
    "character encoding" for what MIME calls a "character set", while
    using the phrase "coded character set" to denote an abstract mapping
    from integers (not octets) to characters.
    That describes terminology similar to Unicode's current terminology, but
    not exactly the same.
    
    Java documentation has also changed over the years with regard to how it
    names these things.
    
    What a muddle.
    
    As this is a Java newsgroup, we are stuck with the inconsistencies of
    the Java documentation, at least to some extent. We are also stuck with
    the ambiguity of some of our terms (note, for instance, the four (four!)
    different definitions of "character" above -- I find that I personally
    use the word in each of those ways). On the other hand, there seem to
    be some points on which there is little disagreement (at least in
    official douments) such as a "font" as a collection of glyphs, a "glyph"
    as a depiction of a character, and a definite distinction between glyphs
    and characters (whatever those are).
    
    Luckilly, in a Java context there is little call for usage of the term
    "character set" in the Unicode sense, so it seems reasonable and
    appropriate that in this venue we should use it in the MIME / Java NIO
    sense (as defined by java.nio.charset.Charset.) "Charset" is a synonym.
    
    By an "encoding" or "character encoding", I think we generally mean what
    Unicode calls a "character encoding scheme" with the implicit
    recognition that in a Java context the "character encoding form" is the
    one defined by Unicode. This is closely related to a "charset" as
    defined in the previous paragraph.
    
    That leaves only "character" of the five terms of interest, and I don't
    think I can do much better than the Unicode glossary there, except to
    note the existence of class java.lang.Character, a related but distinct
    entity. A character is definitely distinct from a glyph -- the latter
    is a possible representation (or part of one) of the former, for some of
    the defintions of the former.
    
    John Bollinger
    email***@***.com