Linux CentOS 6.5 uses your own JDK to modify environment variables

First of all, the default JDK means that after we install the CentOS system comes with the JDK, download and install the JDK itself only need to download, unzip, then the steps are consistent with this article

1. View the location of our default JDK

Instructions:

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1. which Java

Let's go check it out. Discovery is a hyperlink, continue tracking

hyperlinks, Instructions:

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1. Ls-lrt

Keep tracking.

There's a JDK, let's go check it out.

We found the initial jdk1.7 position (i.e. the system current JDK), and we needed the location of the jdk1.6 version, that is, jre-1.6.0-openjdk.x86_64, recorded

/usr/lib/jvm/jre-1.6.0-openjdk.x86_64

2. Modifying environment variables

Instructions:

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1. Vim/etc/profile

In this position I append:

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1. Export java_home=/usr/lib/jvm/jre-1.6.0-openjdk.x86_64
2. Export path= $PATH: $JAVA _home/bin
3. Export classpath=.: $JAVA _home/lib/tools.jar: $JAVA _home/lib/dt.jar

Press ESC to enter: Wq Save and exit

Make environment variables effective

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1. Source/etc/profile

Update JDK

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1. Update-alternatives--install/usr/bin/java Java/usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/java 300
2. Update-alternatives--install/usr/bin/javac Javac/usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/javac 300
3. Update-alternatives--install/usr/bin/jar Jar/usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/jar 300
4. Update-alternatives--config Java

Select the same name, enter the subscript

Test it.

directive: Java-version

found that the JDK version has been modified

Linux CentOS 6.5 uses your own JDK to modify environment variables