1 //aList.java  -- by tsaiwn@csie.nctu.edu.tw
  2 // test  array <---> Collection  (Stack, Vector, List, ...)
  3 import java.util.*;
  4 class aList {
  5     public static void main(String xx[ ]) {
  6        Integer x[ ] = {55, 88, 38, 49, 58};
  7        List<Integer> a = new ArrayList<Integer>(Arrays.asList(x));
  8        print(a);
  9        Collections.sort(a); print(a);
 10        Collections.sort(a, Collections.reverseOrder()); print(a);
 11        testAry(x);
 12        System.out.println("=== after testAry( ):");
 13        print(x);
 14     }
 15     static void print(List x) {
 16        Iterator i = x.iterator( );
 17        for( ;i.hasNext( ); ) System.out.print(" " + i.next( ) );
 18        System.out.println( );
 19     }
 20     static void testAry(Integer y[ ]) {
 21        System.out.println("=== testAry ===");
 22        Vector<Integer> v = new Vector<Integer>(Arrays.asList(y));
 23        v.add(0, 85);  // head
 24        v.add(v.size( ), 66);  // tail
 25        // though we can sort/print Vector ... but ..
 26        Object [ ] yy =  v.toArray( );  // convert to an Array
 27        print(yy);
 28        Arrays.sort(yy);  // yy is an Array
 29        print(yy);
 30        Arrays.sort(yy, Collections.reverseOrder());
 31        print(yy);
 32        y = new Integer[v.size( )];  //  note this will refer to other place
 33        v.copyInto(y);    // please check the content on return
 34        System.out.print("In testAry, y== ");
 35        print(y);
 36     }
 37     static void print(Object b[ ]) {
 38        for(Object x: b) System.out.print(" " + x );    // for each
 39        System.out.println( );
 40     }
 41 }//class
 42 /******************
 43 D:\COURSE\OOP\ppnt>javac aList.java
 44 
 45 D:\COURSE\OOP\ppnt>java aList
 46  55 88 38 49 58
 47  38 49 55 58 88
 48  88 58 55 49 38
 49 === testAry ===
 50  85 55 88 38 49 58 66
 51  38 49 55 58 66 85 88
 52  88 85 66 58 55 49 38
 53 In testAry, y==  85 55 88 38 49 58 66
 54 === after testAry( ):
 55  55 88 38 49 58
 56 
 57 D:\COURSE\OOP\ppnt>
 58 ********************************/