Skip to main content

Joel Liu's Library tagged java   View Popular

13 Aug 06

Java Technology Forums - JNI under Linux


  • I've just written a native library myself and found that the trick is to ensure that the envirnment variable LD_LIBRARY_PATH has been set correctly *before* my java program is invoked.

    In addition; if you are loading a native library from within Tomcat, you must ensure that LD_LIBRARY_PATH has been set *before* you start Tomcat.

    Oh, and by the way: Do not forget to "export" LD_LIBRARY_PATH. Here is a sample:

    export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/path/to/my/directory

    If your .so file also includes other .so files, I think you need to use the "-rpath" option when linking, i.e:

    ld -shared -soname=libmylib.so -rpath /path/to/other/libraries objectfiles

RadRails setup really this painful? help... [Archive] - Ubuntu Forums



  • 0) installed ubuntu, and ruby and rails..



    1) then i installed sun java and set it to be default



    2) then i installed eclipse with synaptic, but it was still using gcj java to run and still sooooo slow so i did this:

    3) apt-get remove --purge java-gcj-compat



    and also i did this:

    4) echo JAVA_HOME=/usr/lib/j2re1.5-sun > ~/.eclipse/eclipserc



    now finally ecliipse was using the sun java and a little peppier.



    but then when i went into add the radrails plugins, it complained about a feature.xml missing? so then i did this:

    5) sudo ln -s /usr/lib/eclipse/features/org.eclipse.rcp.source_3.1.1 /usr/lib/eclipse/features/org.eclipse.rcp_3.1.1

Ubuntu Java — ImageJ Documentation

  • Additionally, you can export the Java classpath in your .bashrc:

    export PATH=/usr/lib/jvm/java-1.5.0-sun/bin:$PATH

    making sure that your 'JAVA_HOME' is set to the proper folder in your .bashrc:

    export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun

    Or make an alias in your .bashrc for 'java':

    alias java='/usr/lib/jvm/java-1.5.0-sun/bin/java'

    (Based on Albert Cardona's email to the mailing list.)

  • By default Ubuntu runs GCJ, the GNU Java, instead of Sun's Java.






    The 'easiest' way to enable Sun's Java is to run it from your launcher. For example:

Setting JAVA_HOME after using java-package - Ubuntu Forums


  • $ echo $JAVA_HOME


  • JAVA_HOME="PATH_TO _YOUR_JAVA_INSTALLATION"

    export JAVA_HOME



    now all you need to do is logout and login again.

Ubuntu Java JRE/JDK installation with java-package - SeriosWiki

  • Example: Choosing which java executable to use:


    update-alternatives --config java


    Example: Choosing which javac executable to use:


    update-alternatives --config javac


    And so on in that fashion for the remaining executables related to Java. You can look in /etc/alternatives to see what one can configure with update-alternatives.

    If you wish to remove some of the JRE/JDKs you have installed, execute (example: for Sun JRE 1.4.2):


    apt-get remove sun-j2re1.4


  • java -version

Java? It's So Nineties

  • Browser pioneer Marc Andreessen, chairman of Zend, a PHP company, says the shift is like the one in the 1990s from traditional programming languages C and C+ to Java. "We're seeing it now with a big migration from Java to PHP in Web development," he says.
  • "I VEHEMENTLY DISAGREE."  Another indicator of possible Java decline comes from shifts in the popularity of books being bought by developers. According to O'Reilly Media, the leading independent publisher of books for programmers, sales of Java-related books are off 4% so far this year, while sales of books related to AJAX, a new Web site-building formula used predominantly with open-source software packages, are up 68%. Java book sales are still much larger, however.

Andreessen: PHP succeeding where Java isn't | Tech News on ZDNet


  • Java enjoyed great success when its inventor, Sun Microsystems, released it in 1995, largely because it was optimized better for programmers than for machines, making software development significantly easier, Andreessen said. Unfortunately, Java has acquired many of the unfavorable characteristics of its predecessors, he added.

3D graphics for Java mobile devices, Part 1: M3G's immediate mode

  • This article, the first in a two-part series, describes the Mobile 3D Graphics
    API (JSR 184). The author introduces you to 3D programming for Java™ mobile
    devices and shows how you can work with lights, cameras, and materials.
1 - 17 of 17
Showing 20 items per page

Highlighter, Sticky notes, Tagging, Groups and Network: integrated suite dramatically boosting research productivity. Learn more »

Join Diigo