how to use goto in java

Question

StartAgain:
    if(nit_arr.size() > 2)
    {
        System.out.println("size of list is more than 2");
        j = prev.size()-2; 
        k = prev.size()-3; 
        if(nit_arr.get(j) == myChoice && nit_arr.get(k) == myChoice){
            //System.out.println("Last 2 selections of nitish are same so next one should not be");
            myChoice = (int )(Math.random() * 2);
            goto StartAgain;
        }
    }

i want to regenerate a random number if last last two elements in the array lists are same and the list is having more than 2 elements in it. its not a loop to use break/continue. so how can i achieve this?

How any don't, instead stucfure your code to work without it using loops — MadProgrammer, Oct 11 '15 at 03:41
Possible duplicate of [Alternative to a goto statement in Java](http://stackoverflow.com/questions/2430782/alternative-to-a-goto-statement-in-java) — resueman, Oct 11 '15 at 03:56

score 2 · Answer 1 · answered Oct 11 '15 at 03:39

2

It's a horrible design decision, but you can use lableled statements in Java. In your case, you might use

continue StartAgain;

But you really should redesign your method. The JLS link for 14.7 says (in part),

Unlike C and C++, the Java programming language has no goto statement; identifier statement labels are used with break (§14.15) or continue (§14.16) statements appearing anywhere within the labeled statement.

answered Oct 11 '15 at 03:39

Elliott Frisch

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i tried this but i got "continue can not be used out of a loop" error? – NIT-SuperUser Oct 11 '15 at 03:43
What version of Java? Also, no version of Java has a `goto`. – Elliott Frisch Oct 11 '15 at 03:46
java versoin 1.8.0_51 – NIT-SuperUser Oct 11 '15 at 03:57

A.S.H · Answer 2 · 2015-10-11T04:11:42.393

    for(bool again = nit_arr.size() > 2; again;)
    {
        System.out.println("size of list is more than 2");
        j = prev.size()-2; 
        k = prev.size()-3; 
        if(nit_arr.get(j) == myChoice && nit_arr.get(k) == myChoice){
            //System.out.println("Last 2 selections of nitish are same so next one should not be");
            myChoice = (int )(Math.random() * 2);
        }
        else{
             again = false;
             // do other stuff if needed
        }
    }

This is how we can achieve it, as well as most other constructions, without the need for a goto statement. Goto is usualy not recommended even in C/C++, because it breaks the structure of the code and makes it more difficult to track (by a human). Sure, everything in the compiled version will be translated into gotos, jumps, etc.

Another way using break; slightly less recommended but ok:

    while(nit_arr.size() > 2)
    {
        System.out.println("size of list is more than 2");
        j = prev.size()-2; 
        k = prev.size()-3; 
        if(nit_arr.get(j) == myChoice && nit_arr.get(k) == myChoice){
            //System.out.println("Last 2 selections of nitish are same so next one should not be");
            myChoice = (int )(Math.random() * 2);
        }
        else break;
    }

how to use goto in java

2 Answers2