break to Exit a 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:
public class Main {
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.");
}
}
This program generates the following output:
i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
Loop complete.
The break statement can be used with while loop as well.
For example, here is the preceding program coded by use of a while loop.
public class Main {
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.");
}
}
The output:
i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
Loop complete.
The break statement can be used with infinite loops.
public class Main {
public static void main(String args[]) {
int i = 0;
while (true) {
if (i == 10){
break; // terminate loop if i is 10
}
System.out.println("i: " + i);
i++;
}
System.out.println("Loop complete.");
}
}
The output:
i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
Loop complete.
When used inside a set of nested loops, the break statement will only break out of
the inner-most loop. For example:
public class Main {
public static void main(String args[]) {
for (int i = 0; i < 5; 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.");
}
}
This program generates the following 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
Pass 3: 0 1 2 3 4 5 6 7 8 9
Pass 4: 0 1 2 3 4 5 6 7 8 9
Loops complete.
The break that terminates a switch statement affects only that switch statement and not any enclosing loops.
public class Main {
public static void main(String args[]) {
for (int i = 0; i < 6; i++)
switch (i) {
case 1:
System.out.println("i is one.");
for (int j = 0; j < 5; j++) {
System.out.println("j is " + j);
}
break;
case 2:
System.out.println("i is two.");
break;
default:
System.out.println("i is greater than 3.");
}
}
}
The output:
i is greater than 3.
i is one.
j is 0
j is 1
j is 2
j is 3
j is 4
i is two.
i is greater than 3.
i is greater than 3.
i is greater than 3.