Java Environment Variables (2.5)

Added by Anthony Whyte, last edited by Aaron Zeckoski on Sep 21, 2009  (view change)

Java requires two environment variables be set for optimal operation. For UNIX operating systems one typically modifies a startup file like ~/.bash_login to set and export shell variables while Mac users typically set and export environment variables in .bash_profile. For Windows, go to Start -> Control Panel -> System -> Advanced -> Environment Variables and set JAVA_HOME via the GUI (samples below).

JAVA_HOME

Set the JAVA_HOME environment variable to point to the base directory of your Java installation.

Linux/Unix/: export JAVA_HOME=/usr/java/java-current
Mac: export JAVA_HOME=/Library/Java/Home
Windows: JAVA_HOME=C:\j2sdk1.5.0_xx ("xx" = the maintenance/revision number, e.g. "j2sdk1.5.0_13")

If your machine has already set the variable JRE_HOME or if you want to use a particular JRE if you have more than one JRE installed on your machine then you'll want to set the JRE_HOME variable as well. JRE_HOME is what Apache Tomcat uses when it starts up, but it defaults to use JAVA_HOME if JRE_HOME is not set. In most cases, setting JAVA_HOME should cover both cases sufficiently.

PATH

Next, add Java's /bin directory to the PATH environment variable:

Linux/Unix/Mac: export PATH=$PATH:$JAVA_HOME/bin/
Windows: append the string ;C:\jdk1.5.0_xx\bin to the end of the system variable named Path ("xx" = the maintenance/revision number, e.g. "j2sdk1.5.0_13")

You should check that you have set your environment variables correctly. For both Windows XP and Unix/Linux/Mac operating systems start a new shell and run the set command to see your environment variables.

$ set

[excerpt]

JAVA_HOME=/Library/Java/Home
...
PATH=/Library/Java/Home/bin [etc]
....
Enter labels to add to this page:
Please wait 
Looking for a label? Just start typing.