Java Vector 二分查找2

import java.util.Vector;
import java.util.Collections;

public class Demo {
   public static void main(String[] args) {
      Vector vec = new Vector();
      vec.add("X");
      vec.add("M");
      vec.add("D");
      vec.add("A");
      vec.add("O");

      Collections.sort(vec);
      System.out.println("Sorted Vector: " + vec);
      int found = Collections.binarySearch(vec, "D");
      System.out.println("Element found at : " + found);
   }
}