Mac 环境变量配置

原文地址

http://www.mkyong.com/java/how-to-set-java_home-environment-variable-on-mac-os-x/

1. Mac OSX 10.5 or later

In Mac OSX 10.5 or later, Apple recommends to set the $JAVA_HOME variable to /usr/libexec/java_home, just export $JAVA_HOME in file ~/. bash_profile or ~/.profile.

$ vim .bash_profile 

 export JAVA_HOME=$(/usr/libexec/java_home)

$ source .bash_profile

$ echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home

Why /usr/libexec/java_home?
This java_home can return the Java version specified in Java Preferences for the current user. For examples,

/usr/libexec/java_home -V
Matching Java Virtual Machines (3):
    1.7.0_05, x86_64:	"Java SE 7"	/Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home
    1.6.0_41-b02-445, x86_64:	"Java SE 6"	/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home
    1.6.0_41-b02-445, i386:	"Java SE 6"	/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home

This Mac OSX has three JDK installed.

##return top Java version
$ /usr/libexec/java_home
/Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home

## I want Java version 1.6
$ /usr/libexec/java_home -v 1.6
/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home