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Sorting arrays of objects


Draco18s

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BlockDescriptor is a Mystcraft API class, it contains block ID, block metadata, and an instability function that returns an integer.

 

I'm trying to sort the array from lowest to highest instability (so that the most unstable material is rarer than the more stable materials).

 

For some reason, allBlocks[0] is ended up as the most unstable (between the 4 blocks I've been using as a test), but the rest of the array is sorted correctly.

 

Input order is Dirt, Diamond Ore, Coal Ore, Birtch Logs (instability values of 0, 1000, 100, 0 respectively).

Output order is Diamond Ore, Dirt, Birtch Logs, Coal Ore.

 

What is wrong with my sort function?

 

 

 

private BlockDescriptor[] sortDescriptors(BlockDescriptor[] allBlocks, int left, int right)
    {
        int pivot = 0;

        if (left < right)
        {
            pivot = partition(allBlocks, left, right, pivot);
            allBlocks = sortDescriptors(allBlocks, left, pivot - 1);
            allBlocks = sortDescriptors(allBlocks, pivot + 1, right);
        }

        return allBlocks;
    }

    private int partition(BlockDescriptor[] allBlocks, int left, int right, int index)
    {
        int pivotValue = allBlocks[index].getInstability(2000);
        //swap pivot to the end
        BlockDescriptor temp = allBlocks[right];
        allBlocks[right] = allBlocks[index];
        allBlocks[index] = temp;
        int storeIndex = left;

        for (int i = left; i < right; i++)
        {
            if (allBlocks[i].getInstability(2000) <= pivotValue)
            {
                temp = allBlocks[i];
                allBlocks[i] = allBlocks[storeIndex];
                allBlocks[storeIndex] = temp;
                storeIndex++;
            }
        }

        temp = allBlocks[right];
        allBlocks[right] = allBlocks[storeIndex];
        allBlocks[storeIndex] = temp;
        return storeIndex;
    }

 

Apparently I'm a complete and utter jerk and come to this forum just like to make fun of people, be confrontational, and make your personal life miserable.  If you think this is the case, JUST REPORT ME.  Otherwise you're just going to get reported when you reply to my posts and point it out, because odds are, I was trying to be nice.

 

Exception: If you do not understand Java, I WILL NOT HELP YOU and your thread will get locked.

 

DO NOT PM ME WITH PROBLEMS. No help will be given.

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