Is there a goto statement in Java?

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醉酒成梦
醉酒成梦 2020-11-22 04:50

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

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  •  野趣味
    野趣味 (楼主)
    2020-11-22 05:54

    It is important to understand that the goto construct is remnant from the days that programmers programmed in machine code and assembly language. Because those languages are so basic (as in, each instruction does only one thing), program control flow is done completely with goto statements (but in assembly language, these are referred to as jump or branch instructions).

    Now, although the C language is fairly low-level, it can be thought of as very high-level assembly language - each statement and function in C can easily be broken down into assembly language instructions. Although C is not the prime language to program computers with nowadays, it is still heavily used in low level applications, such as embedded systems. Because C's function so closely mirrors assembly language's function, it only makes sense that goto is included in C.

    It is clear that Java is an evolution of C/C++. Java shares a lot of features from C, but abstracts a lot more of the details, and therefore is simply written differently. Java is a very high-level language, so it simply is not necessary to have low-level features like goto when more high-level constructs like functions, for, for each, and while loops do the program control flow. Imagine if you were in one function and did a goto to a label into another function. What would happen when the other function returned? This idea is absurd.

    This does not necessarily answer why Java includes the goto statement yet won't let it compile, but it is important to know why goto was ever used in the first place, in lower-level applications, and why it just doesn't make sense to be used in Java.

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