Example of conditional compile in Java

ConditionCompile.md

Conditional Compile in Java

Considering the piece of the code above:

public class ConditionalCompile {
	private static final boolean DEBUG = false;

	public static void main(String args[]) {
		if(DEBUG){
			System.out.println("Hello, world!");
		}
	}
}

After compiled, and use javap to see the result:

public static void main(java.lang.String[]);
    Code:
    Stack=0, Locals=1, Args_size=1
    0:	return
    LineNumberTable: 
    line 8: 0

The whole if statement is gone after compiled because the value of DEBUG is false.