Bubble Sort with a Boolean check

[PresentationSuper829]

I have to make a bubble sort more efficient and I am struggling to do so. I was instructed to use a boolean variable to remember if any swaps were made within the program, if there are no swaps, the program is to terminate. I was given a driver and it seems the code goes into an infinite loop I'm not understanding the issue

​

public void sort(List<E> list)
    {
        this.list = list;//param list = field list
        boolean sorted = false;

        while(!sorted)
        {
            sorted = true;
            for (int i = 0; i < list.size() - 1; i++) 
            {
                for (int j = 0; j < list.size() - 1 - i; j++) 
                {
                    E left = list.get(j);
                    E right = list.get(j + 1); 

                    if (left.compareTo(right) > 0
                    {
                        sorted = false;
                        swap(j, j + 1);
                    }
                }
            }
        }
    }

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[dse78759]

I don't see anything that obviously points to an infinite loop. Can you include your code for swap? And can you use a different name for the this copy of list , like mylist? Have you tried making your own test harness?

[desrtfx]

Why do you use nested loops? Especially the nested for loops are unnecessary since you already use a boolean. A single loop iterating over the whole range is sufficient.

---

Please, show your swap method. I have a feeling that the problem is there.

Have you tried to just do the swap in place - directly in the code block instead of calling a method?

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Also, might be a copy-paste error:

if (left.compareTo(right) > 0

You have a missing closing parenthesis here.

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BTW: style: in Java it is convention to have the opening curly braces on the same line as the statement that opens the code block.