考研失败, 学点Java打小工—

1 编码规范——卫语句

表达异常分支时，少用if-else方式。

比如成绩判断中对于非法输入的处理：

    /*
    >=90   =80    =70    =60    
        //int score = 78;
        //通过Scanner可以实现从控制台输入信息
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入成绩：");
        int score = scanner.nextInt();
        if(score = 70 && score = 60 && score  
  修改后： 
    @Test
    public void test2() {
        //通过Scanner可以实现从控制台输入信息
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入成绩：");
        int score = scanner.nextInt();
        //卫语句1
        if (score  0) {//异常和正常 要分开
            System.out.println("Invalid input!");
            //后面的代码不再执行
            return;
        }
        //卫语句2...
        //合法输入
        if (score >= 90 && score 
            System.out.println("优秀");
        } else if (score = 80 && score = 70 && score = 60 && score  
2 循环控制语句(接Day2) 
 2.2 continue、break
   还是跟C语法相差无几，放个demo了事
   continue：跳出本次循环，继续下一次循环
   break：跳出离他最近的那层循环 
@Test//结果: 1 2 4 5
public void test44() {
    for (int i = 1; i 
        if (i == 3) {
            continue;
        }
        System.out.println(i);
    }
}
@Test//结果: 1 2
public void test45() {
    for (int i = 1; i 
        if (i == 3) {
            break;
        }
        System.out.println(i);
    }
}
@Test//
public void test46() {
    //i,j,k
    for (int i = 1; i 
        System.out.println("i: " + i);
        for (int j = 1; j 
            if (j == 3) {
                break;
            }
            System.out.println("j: " + j);
        }
    }
}

        Scanner scanner = new Scanner(System.in);
        Homework day2 = new Homework();
        System.out.println("please input month: ");
        int month = scanner.nextInt();
        if (month