Java Environment----JDK Development environment Construction and environment variable configuration

1. What is a JDK?

The JDK is the abbreviation for Java Development Kit, which means a toolkit developed by Java programs.

JDK version, a total of three kinds, the Standard Edition (J2SE), Enterprise Edition (Java EE), mobile device Edition (J2ME).

Ordinary users do not need to install the JDK to run Java programs, but only install the JRE (Java Runtime Environment). The program developer must install the JDK to compile and debug the program.

JDK Component content:

2.JDK installation and environment variable configuration in a few steps?

• Installing the JDK

Download site: http://www.oracle.com/

• Environment variable Configuration (3 environment variable settings)

Click Computer-Properties-Advanced system settings, click Environment Variables. Click New under the System Variables column to create a new system environment variable.

(1) New variable name "java_home", variable Value "C:\Java\jdk1.8.0_05" (that is, the JDK installation path)
(2) Edit, variable name "Path", at the end of the value of the original variable plus "; %java_home%\bin;%java_home%\jre\bin "
(3) New variable name "CLASSPATH", Variable Value ".; %java_home%\lib;%java_home%\lib\dt.jar;%java_home%\lib\tools.jar "

• Confirm that the environment is configured correctly

Enter the Java,javac,java-version command in the console to verify that the version number and compiler information for the JDK are present.

3. Example explanation

A diagram explaining the compilation and execution of Java programs.

4. Maintenance such as uninstallation

JDK update once the file content is deleted, it is difficult to uninstall, even if the 360 and professional uninstall JDK tools are difficult to clean up. The query found that the download using Windows cleaner can be completely erased.

Java Environment----JDK Development environment Construction and environment variable configuration