//: c08:SortList.java
// From Thinking in Java, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// A generic sorting list
package c08;
import java.util.*;

public class SortList extends ArrayList {
  private Compare compare; // To hold the callback
  public SortList(Compare comp) {
    compare = comp;
  }
  public void sort() {
    quickSort(0, size() - 1);
  }
  private void quickSort(int left, int right) {
    if(right > left) {
      Object o1 = get(right);
      int i = left - 1;
      int j = right;
      while(true) {
        while(compare.lessThan(
              get(++i), o1))
          ;
        while(j > 0)
          if(compare.lessThanOrEqual(
             get(--j), o1))
            break; // out of while
        if(i >= j) break;
        swap(i, j);
      }
      swap(i , right);
      quickSort(left, i-1);
      quickSort(i+1, right);
    }
  }
  private void swap(int loc1, int loc2) {
    Object tmp = get(loc1);
    set(loc1, get(loc2));
    set(loc2, tmp);
  }
} ///:~