mapdemo.java

来自「地图显示实例」· Java 代码 · 共 52 行

/**
 *  MapDemo.java
 *
 *  $Id: MapDemo.java,v 1.1 2002/03/14 14:10:39 tmh Exp tmh $
 *
 *  $Log: MapDemo.java,v $
 *  Revision 1.1  2002/03/14 14:10:39  tmh
 *  Initial revision
 *
 *  Revision 1.1  2002/03/12 13:59:55  tmh
 *  Initial revision
 *
 *
 **/

/**
 * Purpose:  <<  You decide >>
 *
 * @author      Trudy Howles [e-mail]
 *
**/


import java.util.*;

public class MapDemo {
  
    public static void main (String args[] ) {

        Map m = new HashMap();

        for (int i = 0; i < args.length; i++) {
            Integer frequency = (Integer) m.get (args[i]);
        
            if (frequency == null) {  
                m.put (args[i], new Integer (1));
            } else {
                m.put (args[i], new Integer (frequency.intValue() + 1));
            } 
        }

        System.out.println (m);
   }
}

//  	What is actually stored in the map?  
//	Why don't these print in the order in which they were entered?
//	What is actually printed when the println() statement executes?