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problem:linux:ubuntu_java [2019/04/12 13:13] (current)
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 +====== Ubuntu Java ======
 +
 +**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:
 +
 +  /​usr/​lib/​jvm/​java-1.5.0-sun/​bin/​java -Dplugins.dir=/​home/<​YOURHOME>/​ImageJ ​
 +      -Xmx128m -cp /​opt/​ImageJ/​ij.jar:/​usr/​lib/​jvm/​java-1.5.0-sun/​lib/​tools.jar ij.ImageJ
 +
 +this command line specifies the location of your plugins directory (-Dplugins.dir),​ sets memory to 128 Mb (-Xmx128m) and allows plugins to be compiled (/​usr/​lib/​jvm/​java-1.5.0-sun/​lib/​tools.jar). Note that this is for Sun's Java 1.5 - it will need to be changed accordingly to the version you are running.
 +
 +Additionally,​ you can export the Java classpath in your .bashrc:
 +
 +  export PATH=/​usr/​lib/​jvm/​java-1.5.0-sun/​bin:​$PATH
 +
 +making sure that your '​JAVA_HOME'​ is set to the proper folder in your .bashrc:
 +
 +  export JAVA_HOME=/​usr/​lib/​jvm/​java-1.5.0-sun
 +
 +Or make an alias in your .bashrc for '​java':​
 +
 +  alias java='/​usr/​lib/​jvm/​java-1.5.0-sun/​bin/​java'​
 +
 +(Based on Albert Cardona'​s email to the mailing list.)
 +
 +A Debian-based repository can also be used, contributed and tested by Paolo Ariano. It can be downloaded from: 
 +http://​www.personalweb.unito.it/​paolo.ariano/​software.html
 +
 +===== Java Installation on an Ubuntu based system =====
 +
 +First install the Java version you want/need:
 +
 +  sudo apt-get install sun-java6-jre sun-java6-plugin sun-java6-fonts
 +
 +replace the 6 by 5, if you need a Java 5. You can also replace the jre by jdk if you want a javac.
 +
 +To change the default java command:
 +
 +  sudo update-alternatives --config java
 +
 +and select the Version you want.
 +
 +You can check the result by:
 +
 +  user@ubuntu:​~$ java -version
 +  java version "​1.5.0_15"​
 +  Java(TM) 2 Runtime Environment,​ Standard Edition (build 1.5.0_15-b04)
 +  Java HotSpot(TM) Server VM (build 1.5.0_15-b04,​ mixed mode)
 +
  
problem/linux/ubuntu_java.txt ยท Last modified: 2019/04/12 13:13 (external edit)