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Is there a goto statement in Java?

Asked 2010-03-30T12:30:26.557
299

I'm confused about this. Most of us have been told that there isn't any goto statement in Java.

But I found that it is one of the keywords in Java. Where can it be used? If it can not be used, then why was it included in Java as a keyword?

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3 Answers

224

The Java keyword list specifies the goto keyword, but it is marked as "not used".

It was in the original JVM (see answer by @VitaliiFedorenko), but then removed. It was probably kept as a reserved keyword in case it were to be added to a later version of Java.

If goto was not on the list, and it gets added to the language later on, existing code that used the word goto as an identifier (variable name, method name, etc...) would break. But because goto is a keyword, such code will not even compile in the present, and it remains possible to make it actually do something later on, without breaking existing code.

answered 2010-03-30T12:33:57.280
166

The keyword exists, but it is not implemented.

The only good reason to use goto that I can think of is this:

for (int i = 0; i < MAX_I; i++) {
    for (int j = 0; j < MAX_J; j++) {
        // do stuff
        goto outsideloops; // to break out of both loops
    }
}
outsideloops:

In Java you can do this like this:

loops:
for (int i = 0; i < MAX_I; i++) {
    for (int j = 0; j < MAX_J; j++) {
        // do stuff
        break loops;
    }
}
answered 2010-03-30T12:36:50.117
2

As was pointed out, there is no goto in Java, but the keyword was reserved in case Sun felt like adding goto to Java one day. They wanted to be able to add it without breaking too much code, so they reserved the keyword. Note that with Java 5 they added the enum keyword and it did not break that much code either.

Although Java has no goto, it has some constructs which correspond to some usages of goto, namely being able to break and continue with named loops. Also, finally can be thought of as a kind of twisted goto.

answered 2010-03-30T12:36:17.003

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