Java environment Variables in some of the small knowledge, a previous only know how to match, do not know the meaning of

Each environment variable that you want to set in Java represents the following meanings:
1, specify the JAVA installation directory, in order to use%java_home% later, so as to avoid writing a long string of paths each time: java_home----C:\Program files\sun\java\jdk1.6.0_02
2. Specify the path to the class after loading the Java program to load it in: Classpath----.; %java_home%\lib\tools.jar;%java_home%\lib\dt.jar
Path, this is going to add----to the front of the%java_home%\bin.
3, Tomcat inside the classpath is the same, specify when there is client access, from the server where to load the class into the program.

Java_home: Filled in is the location of the JDK file, path: In the location of the JDK execution, that is, the JDK Bin directory, set up this path, CMD run program can directly to its bin directory to perform operations, classpath: PATH, is to load the Java program to go where the path of the class where to load, representing the path of the Tools.jar and Dt.jar files in the Lib directory, the previous application of java_home to omit to fill those detailed paths

Java environment Variables in some of the small knowledge, a previous only know how to match, do not know the meaning of