Installing Java: the JDK

• The JDK should already be installed on the system. However, you will need to make changes to your login shell (or profile) to access the compiler/interpreter, and to access the library.
• Let's assume the Java Development Kit is installed in

      /usr/local/jdk1.2/
   

  and that the compiler executable is in

      /usr/local/jdk1.2/bin/
   

  and that the library is in

      /usr/local/jdk1.2/lib/
   

• The following instructions are given for C-shell (csh or tcsh). If you are running ksh, you'll need to do a "export".
• First, add the bin directory to your PATH:

      setenv PATH $PATH:/usr/local/jdk1.2/bin
   

• Second, create the CLASSPATH environment variable:

      setenv CLASSPATH /usr/local/jdk1.2/lib:.
   

  (Don't forget the colon and the dot at the end).
• Now, log out and log back in. You should be able to access the compiler and interpreter at the Unix command line:

      % javac
      % java
   

  If not, don't go any further but fix the path problems now.
• Just to be sure, create a HelloWorld.java file, compile and run it:

     public class HelloWorld {
       public static void main (String[] argv)
       {
         System.out.println ("Hello World!");
       }
     }