switch-case和if-else的效率比较·必看（下）

public static void main(String[] args) {
        /**
         * switch与if效率测试·测试次数为100W
         */
        int count=1000000;
        Random ra = new Random();
        Runtime r = Runtime.getRuntime();
        r.gc();//计算内存前先垃圾回收一次
        long start = System.currentTimeMillis();
        long startMem = r.freeMemory(); // 开始Memory
        for (int i = 0; i < count; i++) {
            int ch=ra.nextInt(10);
          if(ch==0){
          }else if(ch==1){
          }else if(ch==2){
          }else if(ch==3){
          }else if(ch==4){
          }else if(ch==5){
          }else if(ch==6){
          }else if(ch==7){
          }else if(ch==8){
          }else if(ch==9){
          }else if(ch==10){
          }
        }
        long endMem =r.freeMemory(); // 末尾Memory
        long end = System.currentTimeMillis();
        System.out.println("if判断"+count+"次用时："+(end-start)+"毫秒");
        System.out.println("内存消耗: "+String.valueOf((startMem- endMem)/1024)+"KB");
    }