Visualize recursion using jGrasp

Question

the one that I like to see how it works graphically is this one

 public boolean splitArray(int[] nums) {
    int index = 0;
    int sum1 = 0;
    int sum2 = 0;

    return recallArray(nums, index, sum1, sum2);

}

public boolean recallArray(int[] nums, int index, int sum1, int sum2){
    if(index >= nums.length){
        return sum1 == sum2;
    }
        int value = nums[index];
        return recallArray(nums,index + 1, sum1 + value,sum2) 
        || recallArray(nums,index + 1, sum1 ,sum2 + value);
}

I try to use Jgrasp , that have a good visual debugger , but it only show me how the variables changes through the recursion calls, it is possible to Jgrasp to do the tree of recursion or something similar?, how?

Questions asking us to recommend or find a book, tool, software library, tutorial or other off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it. — CubeJockey, Sep 02 '15 at 16:05
The question is fine, IMO. I just edited the title to make it specifically about jGrasp. — HRJ, Sep 07 '15 at 16:20

score 0 · Answer 1 · answered Sep 02 '15 at 16:19

0

You could do it yourself with a class (RACheck here) exploiting try-with-resources.

public boolean recallArray(int[] nums, int index, int sum1, int sum2) {
    try (new RACheck(nums, index, sum1, sum2)) {
        if (index >= nums.length) {
            return sum1 == sum2;
        }
        int value = nums[index];
        return recallArray(nums,index + 1, sum1 + value,sum2) 
            || recallArray(nums,index + 1, sum1 ,sum2 + value);
    }
}

class RACheck implements Autocloseable {
    static int recursionDepth;
    int myRecursionDepth;

    final int[] aliasToNums;
    final int[] copyOfNums;

    RAChec(int[] nums, int index, int sum1, int sum2) {
        myRecursionDepth = recursionDepth++;
        // copy initial values.
        this.aliasOfNums = nums;
        this.copyOfNums = Arrays.copyOf(nums, nums.length);
        // dump enter method
    }

    @Override
    public void close() {
        // dump leave method
        // highlight changes to nums
    }
}

answered Sep 02 '15 at 16:19

Joop Eggen

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Despite of syntax errors , the try method , when I declare try ( new RACheck...) throws me an ilegal start of type – Bodhert Sep 02 '15 at 16:32
Try-with-resources exists as of java 7, with java 6 one would need to write `RACheck c = new RACheck(...); try { ... } finally { c.close(); }` – Joop Eggen Sep 02 '15 at 16:46
this is what i tried so far, sorry, im begginer http://pastie.org/10392229 and still not working – Bodhert Sep 02 '15 at 16:53
In old java 6 no `try (c)`. And `finally` section needs to be added. The latter ensures that any return or exception still will call `c.close()`. – Joop Eggen Sep 02 '15 at 16:55

Visualize recursion using jGrasp

1 Answers1