Here is an example if you are going to use OpenJDK. This helps when it’s too slow to load a Java IDE to compile the source files (For example, on Raspberry Pi platform; I’ve tried Geany and Netbeans. It takes forever to load…).

1. From Terminal install the open jdk

   sudo apt-get install openjdk-7-jdk

2. Write program and save the file as filename.java
3. Now to compile use this command from the terminal

   javac filename.java

   If everything work well you will notice a filename.class file is also created.

4. To run your program you compiled use the below code in terminal:

   java filename

NOTE

You can use any text editor (like gedit) ,

replace the filename with watever name you want

you need to be on same directory as the “present working directory” (got by running pwd) while running the command from terminal.