Demo Arrays.sort and Comparable Interface

//****************************************************
// This program demonstrates the Arrays.sort method. *
//****************************************************

import java.util.Arrays;  //for Arrays.sort()
import java.io.File;
import java.util.ArrayList;

//This example demonstrates that the static Arrays.sort() method
// works with objects that implement the Comparable interface


public class SortDemo
{
     public static void main(String [] args)
     {
        String[] lakers = new String[4];
        lakers[0] = "kobe";
        lakers[1] = "zo";
        lakers[2] = "ginobli";
        lakers[3] = "gasol";

        // Arrays.sort()can work on objects that implement
        // the Comparable interface
        for(String s: lakers )
            System.out.print( s + " " );
        System.out.println();

        Arrays.sort( lakers );

        for(String s: lakers )
            System.out.print( s + " " );
        System.out.println();


        Integer[] numbers = { 9, 2, 7, 12, 1 };  //auto box
        // Display the array elements unsorted.
        for(Integer i: numbers )
            System.out.print( i + " " );
        System.out.println();

        // Sort the array.
        Arrays.sort(numbers);

        // Display the array elements sorted.
        for(Integer i: numbers )
            System.out.print( i + " " );
        System.out.println();


        /*
        //run-time error since objects aren't mutually comparable
        Object[] foo = new Object[2];
        foo[0] = new String("joe");
        foo[1] = new Integer( 365 );
        //Arrays.sort(foo);  //run-time error since objects aren't mutually comparable
        for(int i =0; i< foo.length; i++)
            System.out.println(foo[i]);

        */
    }
}