Java break

Summary: in this tutorial, you will learn how to use Java break statement to terminate a loop prematurely.

Introduction to the Java break statement

The break statement allows you to terminate a loop prematurely. You can use the break statement inside a while, do while, and for loop:

break;Code language: JavaScript (javascript)

When Java encounters the break statement within a loop, it terminates the loop immediately. In practice, you use the break statement with an if statement to exit the loop based on a condition like this:

if(condition) {
   break;
}Code language: JavaScript (javascript)

Using break in a for loop

Here’s the syntax for using the break statement in a for loop:

for(initialization; condition, update) {
     // code to be executed
     // ...
     if(exitCondition) {
        break;
     }
     // code to be executed
     // ...
}Code language: Java (java)

The following example illustrates how to use the break statement inside a for loop:

public class App {
    public static void main(String[] args) {
        for (int i = 0; i < 10; i++) {
            if (i == 5) {
                break;
            }
            System.out.println(i);
        }
    }
}Code language: Java (java)

Output:

0
1
2
3
4Code language: plaintext (plaintext)

In this example, we use a for loop to display the integers from 0 to 9. In each iteration, we increase the variable i by one.

When the value of the variable i becomes 5, the condition of the if statement evaluates to true true, and the break statement terminates the loop.

So instead of displaying 10 numbers from 0 to 9, the program shows 5 numbers from 0 to 4. The loop was stopped prematurely.

When you use the break statement inside a nested loop, it terminates the innermost loop only. For example:

public class App {
    public static void main(String[] args) {
        for (int i = 0; i <= 5; i++) {
            for (int j = 0; j <= 5; j++) {
                // exit the inner loop only
                if (j > i) {
                    break;
                }
                // print numbers each row
                System.out.print(j + " ");
            }
            System.out.println();
        }
    }
}Code language: Java (java)

Output:

0 
0 1 
0 1 2 
0 1 2 3 
0 1 2 3 4 
0 1 2 3 4 5Code language: plaintext (plaintext)

Using break in a while loop

The while loop statement executes a block of code repeatedly as long as a condition is true.

By using the break statement with an if statement inside a while loop, you can create another condition that terminates the loop:

while (condition)
{
    if (exitCondition)
    {
        break;
    }
}Code language: Java (java)

The following example illustrates how to use the break statement inside a while loop to terminate the loop when the count is 5:

public class App {
    public static void main(String[] args) {
        int count = 0;
        while (count <= 10) {
            // Exit the loop when count equals 5
            if (count == 5) {
                break;
            }
            System.out.println(count);
            count++;
        }
    }
}Code language: Java (java)

Output:

0
1
2
3
4

In this program, the loop will terminate when the count equals 5 and will print numbers from 0 to 4.

Using break in do while loop

Similar to the while loop, you can use the break statement in a do while loop to exit the loop prematurely:

do
{
    if (exitCondition)
    {
        break;
    }
} while (condition);Code language: Java (java)

For example, the following program illustrates how to use the break statement in a do while loop:

public class App {
    public static void main(String[] args) {
        int count = 0;
        do {
            if (count == 5) {
                break;
            }
            System.out.println(count);
            count++;
        } while (count < 10);
    }
}Code language: Java (java)

In this program, the loop will terminate when the count equals 5 and will print numbers from 0 to 4.

Summary

• Use the Java break statement to terminate a loop prematurely.