在Java中,如何跳出当前的多重嵌套循环?

时间:2021-12-08 15:51:13

在Java中,如何跳出当前的多重嵌套循环?

package cn.hgnulb.package0324;

/**
 * 参考:https://blog.csdn.net/amen_wu/article/details/53913319
 */
public class Demo {
    public static void main(String[] args) {
        System.out.println("方法一:标号方式");
        outerloop:
        for (int i = 1; i < 5; i++) {
            for (int j = 1; j < 5; j++) {
                if (i * j > 6) {
                    System.out.println("Breaking");
                    break outerloop;
                }
                System.out.println(i + " " + j);
            }
        }
        System.out.println("Done");

        System.out.println("方法二:条件控制");
        boolean finished = false;
        for (int i = 1; i < 5 && !finished; i++) {
            for (int j = 1; j < 5; j++) {
                if (i * j > 6) {
                    System.out.println("Breaking");
                    finished = true;
                    break;
                }
                System.out.println(i + " " + j);
            }
        }
        System.out.println("Done");

        System.out.println("方法二变形:条件控制");
        for (int i = 1; i < 5; i++) {
            for (int j = 1; j < 5; j++) {
                if (i * j > 6) {
                    System.out.println("Breaking");
                    i = 5;
                    break;
                }
                System.out.println(i + " " + j);
            }
        }
        System.out.println("Done");

        System.out.println("方法三:抛出异常");
        try {
            for (int i = 1; i < 5; i++) {
                for (int j = 1; j < 5; j++) {
                    if (i * j > 6) {
                        System.out.println("Breaking");
                        throw new Exception();
                    }
                    System.out.println(i + " " + j);
                }
            }
            System.out.println("Done");// 此行代码不会执行
        } catch (Exception e) {
            // System.out.println("e");
        }
    }
}

参考答案

方法一:标号方式
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking
Done
方法二:条件控制
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking
Done
方法二变形:条件控制
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking
Done
方法三:抛出异常
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking

方法一:标号方式

System.out.println("方法一:标号方式");
outerloop:
for (int i = 1; i < 5; i++) {
    for (int j = 1; j < 5; j++) {
        if (i * j > 6) {
            System.out.println("Breaking");
            break outerloop;
        }
        System.out.println(i + " " + j);
    }
}
System.out.println("Done");

参考答案

方法一:标号方式
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking
Done

方法二:条件控制

System.out.println("方法二:条件控制");
boolean finished = false;
for (int i = 1; i < 5 && !finished; i++) {
    for (int j = 1; j < 5; j++) {
        if (i * j > 6) {
            System.out.println("Breaking");
            finished = true;
            break;
        }
        System.out.println(i + " " + j);
    }
}
System.out.println("Done");

参考答案

方法二:条件控制
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking
Done
System.out.println("方法二变形:条件控制");
for (int i = 1; i < 5; i++) {
    for (int j = 1; j < 5; j++) {
        if (i * j > 6) {
            System.out.println("Breaking");
            i = 5;
            break;
        }
        System.out.println(i + " " + j);
    }
}
System.out.println("Done");

参考答案

方法二变形:条件控制
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking
Done

方法三:抛出异常

System.out.println("方法三:抛出异常");
try {
    for (int i = 1; i < 5; i++) {
        for (int j = 1; j < 5; j++) {
            if (i * j > 6) {
                System.out.println("Breaking");
                throw new Exception();
            }
            System.out.println(i + " " + j);
        }
    }
    System.out.println("Done");// 此行代码不会执行
} catch (Exception e) {
    // System.out.println("e");
}

参考答案

方法三:抛出异常
1 1
1 2
1 3
1 4
2 1
2 2
2 3
Breaking