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How to remove duplicate values in an array.

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I have some code to build an object elementData that stores a list of ints in an array and also keeps track of a boolean unique that determines if duplicates are allowed in a list. I have written a small method to search out duplicates and remove them, but for some reason it is not working. I am not sure if the problem is with the method itself or the placement of the call to the removeDuplicates method.

   // post: places the value in the correct place based on ascending order
   public void add(int value) {
      size++;
      if (size == 1) {   
         elementData[0] = value;
      } else {
         int position =  Arrays.binarySearch(elementData, 0, size - 1, value);
         if (position < 0 ) {
            position = (-position) - 1;
         }
         for (int i = size - 1; i > position; i--) {
            elementData[i] = elementData[i - 1];
         }
         elementData[position] = value;
         if (unique) {
            removeDuplicates();
         }
      }
   }
      
   //post: removes any duplicate values from the list
   private void removeDuplicates() {
      for(int i = size - 1; i < 0; i--) {
         if (elementData[i] == elementData[i - 1]){
            remove(i);
         }
      }
   }
   // pre : 0 <= index < size() (throws IndexOutOfBoundsException if not)
   // post: removes value at the given index, shifting subsequent values left
   public void remove(int index) {
      checkIndex(index);
      for (int i = index; i < size - 1; i++) {
         elementData[i] = elementData[i + 1];
      }
      size--;
   }

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How to remove duplicate values in an array. miss.smileyfish@gmail.com - 2013-10-12 22:18 -0700
  Re: How to remove duplicate values in an array. Steven Simpson <ss@domain.invalid> - 2013-10-13 10:00 +0100
  Re: How to remove duplicate values in an array. Joerg Meier <joergmmeier@arcor.de> - 2013-10-13 12:09 +0200
  Re: How to remove duplicate values in an array. Roedy Green <see_website@mindprod.com.invalid> - 2013-10-21 20:34 -0700
    Re: How to remove duplicate values in an array. Lew <lewbloch@gmail.com> - 2013-10-23 15:58 -0700

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