JAVA_HOME, classpath are well established in the system variables;
J ava_home add jdk installation directory, pay attention to writing correct java_home: Do not install directory behind a semicolon.
The corresponding value classpath is;.% Java_home% \ lib \ dt.jar;% java_home% \ lib \ tools.jar attention to this place not to miss the foremost point.
Later add the value of the original path;% java_home% \ bin;% java_home% \ jre \ bin