How can I use jump statements in Java correctly?

General Discussions
,
1

I’m trying to use a label with continue in Java but getting an error.

Here’s my code:

public class Test {
    public static void main(String[] args) {
        continue s;
        System.out.println("I am not supposed to print this");
        s:
        System.out.println("I am supposed to print this");
    }
}

The error I get is:

java: undefined label: s

What am I doing wrong, and how should I properly use java jump statements like continue or break with labels?

2

Labels must be placed before a loop, and continue must be inside that loop:

public class Test {
    public static void main(String[] args) {
        s: // Label before the loop
        for (int i = 0; i < 5; i++) {
            if (i == 2) {
                continue s; // Skips the current iteration and jumps to the next loop iteration
            }
            System.out.println("i: " + i);
        }
    }
}

Expected Output:

i: 0
i: 1
i: 3
i: 4

The label must be before the loop.

continue s; skips only when i == 2, so i: 2 is missing.

3

If you want to exit an outer loop, use break with a label:

public class Test {
    public static void main(String[] args) {
        s: // Label before the loop
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < 5; j++) {
                if (i == 2 && j == 2) {
                    break s; // Exits both loops when i = 2 and j = 2
                }
                System.out.println("i: " + i + ", j: " + j);
            }
        }
    }
}

:white_check_mark: Expected Output:

i: 0, j: 0
i: 0, j: 1
i: 0, j: 2
...
i: 1, j: 4
i: 2, j: 0
i: 2, j: 1

When i == 2 && j == 2, both loops exit using break s;.

This works only inside a loop.

4

If you’re inside a method and want to exit early (similar to a jump statement), you can use return:

public class Test {
    public static void main(String[] args) {
        printNumbers();
        System.out.println("This will not print after return.");
    }

    public static void printNumbers() {
        for (int i = 0; i < 5; i++) {
            if (i == 2) {
                return; // Exits the method completely
            }
            System.out.println("i: " + i);
        }
        System.out.println("This will not print if i == 2");
    }
}

:white_check_mark: Expected Output:

i: 0
i: 1

:white_check_mark: Why?

When i == 2, return exits the method immediately.

Unlike break, which exits only a loop, return stops method execution.