Compiling the Program

To compile the Example program, execute the compiler, javac, specifying the name of the source file on the command line, as shown here:

javac Example.java

The javac compiler creates a file called Example.class that contains the bytecode version of the program. Remember, bytecode is not executable code. Bytecode must be executed by a Java Virtual Machine. Thus, the output of javac is not code that can be directly executed. 

To actually run the program, you must use the Java interpreter, java. To do so, pass the class name

Example  as a command-line argument, as shown here: 

java Example

When the program is run, the following output is displayed: Java drives the Web. When Java source code is compiled, each individual class is put into its own output file named after the class and using the .class extension. This is why it is a good idea to give your Java source files the same name as the class they contain—the name of the source file will match the name of the .class

file. When you execute the Java interpreter as just shown, you are actually specifying the name of the class that you want the interpreter to execute. It will automatically search for a file by that name that has the .class extension. If it finds the file, it will execute the code contained in the specified class.