Break_KetWord
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break Keyword in Java with Examples
The break keyword is used to prematurely exit a for, while, or do while loop or to mark the end of a case block in a switch statement.
Let’s discuss how to use break keyword in for loop, while loop and switch statement with examples.
1. Using a break keyword 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.```
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: