java - 关于 Java 中的标签表现得像 GOTO

Question

这不应该无限循环吗？

someLabel:{
        for (int i = 0; i < 5; ++i) {
            System.out.println(i);
            if (i == 3)
                break someLabel;
        }
}

开始了

0
1
2
3

然后死了。我正在阅读有关 Java 中 GOTO 替代方法的问题。这是公认的答案:https://stackoverflow.com/a/2430789/555690 . for循环是不是应该再执行一次？

Answer 1

来自 http://docs.oracle.com/javase/tutorial/java/nutsandbolts/branch.html :

The break statement terminates the labeled statement; it does not transfer the flow of control to the label. Control flow is transferred to the statement immediately following the labeled (terminated) statement.

除了我从未见过任何使用这种控制流的真实代码之外，我猜它的用途是从内循环中断开外循环(如提供的链接中所述):

search:
    for (i = 0; i < arrayOfInts.length; i++) {
        for (j = 0; j < arrayOfInts[i].length;
             j++) {
            if (arrayOfInts[i][j] == searchfor) {
                foundIt = true;
                break search;
            }
        }
    }