freeCodeCamp/guide/english/java/loops/infinite-loops/index.md

title
Infinite Loops

Infinite Loops

An infinte loop is a loop statement (for, while, do-while) which does not end on its own.

The test condition of a looping statement decides whether the loop body will execute or not. So a test condition which is always true will keep on executing the body of the loop, forever. That's the case in an infinte loop.

Examples:

// Infinite For Loop
for ( ; ; )
{
    // some code here
}

// Infinite While Loop
while (true)
{
    // some code here
}

// Infinite Do While Loop
do
{
    // some code here
} while (true);

Normally, if your loop is running infinitely, it is an error that should not occur as an infinite loop does not stop and prevents the rest of the program from running.

for(int i=0;i<100;i++){

    if(i==49){
    i=0;
    }

}

The loop above runs infinitely because every time i approaches 49, it is set to be 0.This is to say that i never reaches 100 to terminate the loop, so the loop is an infinite loop.

But a program stuck in such a loop will keep using computer resources indefinitely. This is undesirable, and is a type of 'run-time error'.

To prevent the error, programmers use a break statement to break out of the loop. The break executes only under a particular condition. Use of a selection statement like if-else ensures the same.

while (true)
{
    // do something
    
    if(conditionToEndLoop == true)
        break;
    
    // do more
}

The main advantage of using an infinite loop over a regular loop is readability.

Sometimes, the body of a loop is easier to understand if the loop ends in the middle, and not at the end/beginning. In such a situation, an infinite loop will be a better choice.