Java Tutorial/Statement Control/Break Statement

Breaking Indefinite Loops

   <source lang="java">

public class MainClass {

 public static void main(String[] args) {
   OuterLoop: for (int i = 2;; i++) {
     for (int j = 2; j < i; j++) {
       if (i % j == 0) {
         continue OuterLoop;
       }
     }
     System.out.println(i);
     if (i == 107) {
       break;
     }
   }
 }

}</source>

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37
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67
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101
103
107

Labelled breaks breaks out of several levels of nested loops inside a pair of curly braces.

   <source lang="java">

public class Main {

 public static void main(String args[]) {
   int len = 100;
   int key = 50;
   int k = 0;
   out: {
     for (int i = 0; i < len; i++) {
       for (int j = 0; j < len; j++) {
         if (i == key) {
           break out;
         }
         k += 1;
       }
     }
   }
   System.out.println(k);
 }

}</source>

The break Statement

1. The break statement is used to break from an enclosing do, while, for, or switch statement.
2. It is a compile error to use break anywhere else.
3. "break" breaks the loop without executing the rest of the statements in the block.

For example, consider the following code

   <source lang="java">

public class MainClass {

 public static void main(String[] args) {
   int i = 0;
   while (true) {
       System.out.println(i);
       i++;
       if (i > 3) {
           break;
       }
   }
 }

}</source>

The result is

0
1
2
3

The Labeled break Statement

1. The break statement can be followed by a label.
2. The presence of a label will transfer control to the start of the code identified by the label.
3. For example, consider this code.

   <source lang="java">

public class MainClass {

 public static void main(String[] args) {
   OuterLoop: for (int i = 2;; i++) {
     for (int j = 2; j < i; j++) {
       if (i % j == 0) {
         continue OuterLoop;
       }
     }
     System.out.println(i);
     if (i == 37) {
       break OuterLoop;
     }
   }
 }

}</source>

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37

Using the break Statement in a Loop: break out from a loop

   <source lang="java">

public class MainClass {

 public static void main(String[] args) {
   int count = 50;
   for (int j = 1; j < count; j++) {
     if (count % j == 0) {
       System.out.println("Breaking!!");
       break;
     }
   }
 }

}</source>

Breaking!!