It's illegal to have more than one case label using the same value. : switch « Statements « SCJP

1. SCJP
2. Statements
3. switch

public class MainClass{
    public static void main(String[] argv){
        int temp = 90;
        switch(temp) {
          case 80 :  System.out.println("80");
          case 80 :  System.out.println("80");   // won't compile!
          case 90 :  System.out.println("90");
          default :  System.out.println("default");
        }
    }
}

Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
	Duplicate case
	Duplicate case

	at MainClass.main(MainClass.java:5)