Java break Statement with Examples

In this quick article, we will discuss how to use break keyword in for loop, while loop, switch-case statement and in nested loops with examples.
In Java, the break statement has three uses. First, it terminates a statement sequence in a switch statement. Second, it can be used to exit a loop(for loop, while loop etc). Third, it can be used as a “civilized” form of goto.

Table of contents

  1. Using a break to Exit a for Loop
  2. Using break to Exit a while Loop
  3. Using break with Nested Loops
  4. Using break with a switch case Statement
  5. Using break as a Civilized Form of goto

1. Using a break to Exit a for Loop

By using a break, you can force immediate termination of a loop, bypassing the conditional expression and any remaining code in the body of the loop. When a break statement is encountered inside a loop, the loop is terminated and program control resumes at the next statement following the loop.
Here is a simple example:
package net.javaguides.corejava.controlstatements.loops;

public class BreakWithForLoop {
    public static void main(String args[]) {
        for (int i = 0; i < 100; i++) {
            if (i == 10)
                break; // terminate loop if i is 10
            System.out.println("i: " + i);
        }
        System.out.println("Loop complete.");
    }
}
Output:
i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
Loop complete.
As we can see, although the for loop is designed to run from 0 to 99, the break statement causes it to terminate early, when i equals 10.

2. Using break to Exit a while Loop

package net.javaguides.corejava.controlstatements.loops;

public class BreakWithWhileLoop {
    public static void main(String args[]) {
        int i = 0;
        while (i < 100) {
            if (i == 10)
                break; // terminate loop if i is 10
            System.out.println("i: " + i);
            i++;
        }
        System.out.println("Loop complete.");
    }
}
Output:
i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
Loop complete.

3. Using break with Nested Loops

When break keyword used inside a set of nested loops, the break statement will only break out of the innermost loop. 
For example:
package net.javaguides.corejava.controlstatements.loops;

public class BreakWithNestedLoops {
    public static void main(String args[]) {
        for (int i = 0; i < 3; i++) {
            System.out.print("Pass " + i + ": ");
            for (int j = 0; j < 100; j++) {
                if (j == 10)
                    break; // terminate loop if j is 10
                System.out.print(j + " ");
            }
            System.out.println();
        }
        System.out.println("Loops complete.");
    }
}
Output:
Pass 0: 0 1 2 3 4 5 6 7 8 9 
Pass 1: 0 1 2 3 4 5 6 7 8 9 
Pass 2: 0 1 2 3 4 5 6 7 8 9 
Loops complete.
As we can see, the break statement in the inner loop only causes termination of that loop. The outer loop is unaffected.

4. Using break with a switch case Statement

public class BreakSwitchCaseExample {

    public static void main(String args[]) {
        int num = 2;

        switch (num) {
            case 1:
                System.out.println("Case 1 ");
                break;
            case 2:
                System.out.println("Case 2 ");
                break;
            case 3:
                System.out.println("Case 3 ");
                break;
            default:
                System.out.println("Default ");
        }
    }
}
Output:
Case 2

5. Using break as a Civilized Form of goto

We can use a break statement with a label. This feature is introduced since JDK 1.5. So, we can break any loop in Java now whether it is an outer loop or inner.
package net.javaguides.corejava.controlstatements.loops;

public class BreakGoto {
    public static void main(String args[]) {
        boolean t = true;
        first: {
            second: {
                third: {
                    System.out.println("Before the break.");
                    if (t)
                        break second; // break out of second block
                    System.out.println("This won't execute");
                }
                System.out.println("This won't execute");
            }
            System.out.println("This is after second block.");
        }
    }
}
Output:
Before the break.
This is after second block.


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