How Do 'break' and 'continue' Statements Use Labels to Control Loop Execution in Java?

Understanding the "loop:" mark in Java code

In Java code, an unusual code snippet can cause confusion:

 loop:<br>for (;;) {</p>
<div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false">// ...

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}

This construction uses the mark "loop", which at first glance looks like may seem like a keyword, but is actually a label.

What are Labels?

Labels represent named destinations that can be navigated to in jumps. They are declared with an identifier followed by a colon (:).

Use of labels

Labels are used together with jump statements such as "break" and "continue". The jump statements can reference labels to branch execution to a specific point.

In the provided code snippet, the label "loop" is declared before the infinite loop. This makes it possible to exit the loop using the "break loop" statement. This construction is often used to break nested loops.

Example:

The following example shows the use of a label to break a nested loop:

<br>loop1:<br>for (int i = 0; i < 10; i ) {</p>
<div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false">loop2:
for (int j = 0; j < 10; j++) {
    if (condition) {
        // Durchbreche die äußere Schleife
        break loop1;
    }
}

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