JAVA Setting the meaning of environment variables (java_home,path,classpath)

Before developing a Java program, you need to install and configure the Java Development environment on a computer line. One is to install myeclipse directly, use its own JDK compilation to run, or install the JDK under our Windows or Linux platform to configure environment variables. (with the JDK version updated, the MyEclipse default JDK is the same, unless you upgrade the latest version of MyEclipse) to install the JDK under the operating system platform, the most troublesome is to configure environment variables:

1, Java_home(Windows is case-insensitive, the Linux system is case-sensitive) The installation path of the JDK.

Blogger's JDK is installed by default, C:\Program files\java\jdk1.8.0_91 Java_home itself does not make any sense, its purpose is convenient to the path and CLASSPATH configuration Java_home itself does not have any meaning, Its purpose is to facilitate the configuration of path and classpath paths

2, Path since the JDK installed in the computer, and the JDK installation path also contains Java and javac two commands, but the computer does not know where to find the two commands.  If you can find this command, the change command is executable. namely: C:\Program Files\java\jdk1.8.0_91\bin. Of course, if you set Java_home, you can also%java_home%\bin; When the Java_home value changes, you do not have to modify the path.

3, CLASSPATH after the configuration has completed path, the Java class can be fully compiled and generated under the current path of the class file. When executing classes with Java commands, where should the JRE go to search for Java classes? So use Classpath to make the JRE path search Java class. In previous versions of JDK1.4, you would need to add (.) to the CLASSPATH environment variable to set the current path, whereas a JRE above the JDK1.5 version would automatically search for class files under the current path, and the system could automatically load Java classes in Dt.jar and Tools.jar files, no longer having to set class Path environment variable.

All in all, after the JDK1.5 version of the environment variable, we just need to configure path. This is the command to have the computer find Java.

2016-08-19 15:00:00

JAVA Setting the meaning of environment variables (java_home,path,classpath)