switch中break用法

switch 与break用法

        byte a = 2;
        switch (a) {
        case 1:
            System.out.println(" A ");
            break;
        case 2:
            System.out.println(" B ");
        case 3:
            System.out.println(" C ");
        case 4:
            System.out.println(" D ");
            break;
        default:
            System.out.println(" default ");
        }

 B 
 C 
 D 

对应流程图