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Trail: Learning the Java Language
Lesson: The Nuts and Bolts of the Java Language

## Branching Statements

> You saw the `break` statement in action within the `switch` statement earlier. As noted there, `break` causes the flow of control to jump to the statement immediately following the current statement.

> Another form of the `break` statement causes flow of control to break out of a labeled statement. You label a statement by placing a legal Java identifier (the label) followed by a colon (:) before the statement:

> >     statementName: someJavaStatement

> To break out of the statement labeled `statementName` use the following form of the `break` statement.

> >     break statementName;

> Labeled breaks are an alternative to the `goto` statement, which is not supported by the Java language.

> Use the `continue` statement within loops to jump to another statement.

> > Note: The `continue` statement can only be called from within a loop.

> The `continue` statement has two forms: unlabeled and labeled. If you use the unlabelled form, the loop skips to the end of the loop's body and evaluates the loop's test.

> The labeled form of the `continue` statement continues at the next iteration of the labeled loop. Consider this implementation of the `String` class's `indexOf` method which uses the labeled form of `continue`:

> >     public int indexOf(String str, int fromIndex) {
> >         char[] v1 = value;
> >         char[] v2 = str.value;
> >         int max = offset + (count - str.count);
> >       test:
> >         for (int i = offset + ((fromIndex < 0) ? 0 : fromIndex);
> >              i <= max ; i++)
> >         {
> >             int n = str.count;
> >             int j = i;
> >             int k = str.offset;
> >             while (n-- != 0) {
> >                 if (v1[j++] != v2[k++]) {
> >                     continue test;
> >                 }
> >             }
> >             return i - offset;
> >         }
> >         return -1;
> >     }

> The last of Java's branching statements the `return` statement. You use `return` to exit from the current method and jump back to the statement within the calling method that follows the original method call. There are two forms of `return`: one that returns a value and one that doesn't. To return a value, simply put the value (or an expression that calculates the value after the `return` keyword:

> >     return ++count;

> The value returned by `return` must match the type of method's declared return value.

> When a method is declared `void` use the form of `return` that doesn't return a value:

> >     return;

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