When running Java application, the hint cannot find Java_home, query java-version
[Jifeng@localhost bin]$ java-version
java Version "1.7.0_09-icedtea" OpenJDK the Runtime Environment
( rhel-2.3.4.1.el6_3-i386)
OpenJDK Client VM (build 23.2-b09, Mixed mode)
Centos 6.4 has a OPENJDK environment, but you need to manually configure the Java_home environment variables.
But OpenJDK's installation directory is different from our common Sun JDK storage location directory.
OpenJDK installed directory is located in:/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.9
Other versions are under/USR/LIB/JVM, including JRE and JDK.
Can see "Bin" under "java-1.7.0-openjdk-1.7.0.9" directory, can find Javac file under Bin, explain this is JDK.
At this point only need to open the environment variable file Vim/etc/profile in the terminal, (Save the command press ESC, then enter ": w" to save, and then ": Q" Exit VI) fill in the appropriate directory can:
Export java_home=/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.9
Export classpath=.: $JAVA _home/jre/lib/rt.jar: $JAVA _home/lib/dt.jar: $JAVA _home/lib/tools.jar
Export path= $PATH: $JAVA _home/bin
This allows us to set the JDK, in the input source/etc/profile can be effective.