Java中的Switch Case语句及示例详解

switch (variable or an integer expression)
{
     case constant:
     //Java code
     ;
     case constant:
     //Java code
     ;
     default:
     //Java code
     ;
}

public class SwitchCaseExample1 {
   public static void main(String args[]){
     int num=2;
     switch(num+2)
     {
        case 1:
	  System.out.println("Case1: Value is: "+num);
	case 2:
	  System.out.println("Case2: Value is: "+num);
	case 3:
	  System.out.println("Case3: Value is: "+num);
        default:
	  System.out.println("Default: Value is: "+num);
      }
   }
}

public class SwitchCaseExample2 {
   public static void main(String args[]){
      int i=2;
      switch(i)
      {
	 case 1:
	   System.out.println("Case1 ");
	 case 2:
	   System.out.println("Case2 ");
	 case 3:
	   System.out.println("Case3 ");
	 case 4:
           System.out.println("Case4 ");
	 default:
	   System.out.println("Default ");
      }
   }
}

public class SwitchCaseExample2 {
   public static void main(String args[]){
      int i=2;
      switch(i)
      {
	 case 1:
	   System.out.println("Case1 ");
	   break;
	 case 2:
	   System.out.println("Case2 ");
	   break;
	 case 3:
	   System.out.println("Case3 ");
	   break;
	 case 4:
           System.out.println("Case4 ");
           break;
	 default:
	   System.out.println("Default ");
      }
   }
}