After the J2SDK is installed, you need to configure the environment variables to generally configure 2 variables: java_home, ClassPath, if the J2SDK is installed in the C: / J2SDK directory, then: java_home = c: / j2sdkclasspath =.;% Java_home% / liba In the JDK version, ClassPath is a classpath =.;% Java_home% / lib / Tools.jar;% java_home% / lib / dt.jar seems to be from a version of J2SDK1.4, Just configure it to the directory.
In addition, you can add% java_home% / bin in the path, so you can run Javac to compile Java programs directly in the command line.
