人在江湖

   1: //抽象享元角色

   2: abstract public class Flyweight

   3: {

   4:     abstract public void operation(String state);

   5: }

   6:  

   1: //具体享元(ConcreteFlyweight)角色

   2: public class ConcreteFlyweight extends Flyweight

   3: {

   4:     private Character intrinsicState = null;

   5:  

   6:  public ConcreteFlyweight(Character state)

   7:  {

   8:   this.intrinsicState = state;

   9:  }

  10:  

  11:  public void operation(String state)

  12:  {

  13:   System.out.print( "\nIntrinsic State = " + intrinsicState +

  14:             ", Extrinsic State = " + state);

  15:  }

  16: }

  17:  

   1: //享元工厂(FlyweightFactory)角色

   2: import java.util.Map;

   3: import java.util.HashMap;

   4: import java.util.Iterator;

   5:  

   6: public class FlyweightFactory

   7: {

   8:     private HashMap flies = new HashMap();

   9:     /**

  10:      * @link aggregation

  11:      * @directed

  12:      * @clientRole Flyweights

  13:      */

  14:     private Flyweight lnkFlyweight;

  15:  

  16:  public FlyweightFactory(){}

  17:  

  18:  public synchronized Flyweight factory(Character state)

  19:  {

  20:   if ( flies.containsKey( state ) )

  21:         {

  22:             return (Flyweight) flies.get( state );

  23:         }

  24:         else

  25:         {

  26:    Flyweight fly = new ConcreteFlyweight( state );

  27:             flies.put( state , fly);

  28:             return fly;

  29:         }

  30:  }

  31:  

  32:  public void checkFlyweight()

  33:  {

  34:   Flyweight fly ;

  35:         int i = 0;

  36:  

  37:         System.out.println("\n==========checkFlyweight()=============");

  38:   for ( Iterator it = flies.entrySet().iterator() ; it.hasNext() ;  )

  39:         {

  40:    Map.Entry e = (Map.Entry) it.next();

  41:             System.out.println("Item " + (++i) + " : " + e.getKey());

  42:         }

  43:         System.out.println("==========checkFlyweight()=============");

  44:  }

  45:  

  46: }

  47:  

   1:  

   2: //客户端(Client)角色

   3: public class Client

   4: {

   5:     private static FlyweightFactory factory;

   6:  

   7:     static public void main(String[] args)

   8:  {

   9:   factory = new FlyweightFactory();

  10:  

  11:   Flyweight fly = factory.factory(new Character('a'));

  12:   fly.operation("First Call");

  13:   

  14:   fly = factory.factory(new Character('b'));

  15:   fly.operation("Second Call");

  16:   

  17:   fly = factory.factory(new Character('a'));

  18:   fly.operation("Third Call");

  19:   

  20:   // intrinsic Flyweight

  21:   factory.checkFlyweight();

  22:  }

  23: }

  24:  

   1: //抽象享元角色

   2: abstract public class Flyweight

   3: {

   4:     abstract public void operation(String state);

   5: }

   1: //具体享元(ConcreteFlyweight)角色

   2: public class ConcreteFlyweight extends Flyweight

   3: {

   4:     private Character intrinsicState = null;

   5:  

   6:  public ConcreteFlyweight(Character state)

   7:  {

   8:   this.intrinsicState = state;

   9:  }

  10:  

  11:  public void operation(String state)

  12:  {

  13:   System.out.print( "\nInternal State = " +

  14:             intrinsicState + " Extrinsic State = " + state );

  15:  }

  16: }

  17:  

   1: //复合享元(UnsharableFlyweight)角色

   2: import java.util.Map;

   3: import java.util.HashMap;

   4: import java.util.Iterator;

   5:  

   6: public class ConcreteCompositeFlyweight extends Flyweight

   7: {

   8:     private HashMap flies = new HashMap(10);

   9:  

  10:     /**

  11:      * @link aggregation

  12:      * @directed

  13:      * @clientRole Composite

  14:      */

  15:     private Flyweight flyweight;

  16:  

  17:  public ConcreteCompositeFlyweight()

  18:  {

  19:  }

  20:  

  21:  public void add(Character key, Flyweight fly)

  22:  {

  23:   flies.put(key, fly);

  24:  }

  25:  

  26:  public void operation(String extrinsicState)

  27:  {

  28:         Flyweight fly =  null;

  29:  

  30:   for ( Iterator it = flies.entrySet().iterator() ; it.hasNext() ;  )

  31:         {

  32:    Map.Entry e = (Map.Entry) it.next();

  33:             fly = (Flyweight) e.getValue();

  34:  

  35:             fly.operation(extrinsicState);

  36:         }

  37:  }

  38: }

  39:  

   1: //享元工厂(FlyweightFactory)角色

   2: import java.util.Map;

   3: import java.util.HashMap;

   4: import java.util.Iterator;

   5:  

   6: public class FlyweightFactory

   7: {

   8:     private HashMap flies = new HashMap();

   9:     /**

  10:      * @link aggregation

  11:      * @directed

  12:      * @clientRole Flyweights

  13:      */

  14:     private Flyweight lnkFlyweight;

  15:  

  16:  public FlyweightFactory(){}

  17:  

  18:  public Flyweight factory(String compositeState)

  19:  {

  20:   ConcreteCompositeFlyweight compositeFly = new ConcreteCompositeFlyweight();

  21:   

  22:   int length = compositeState.length();

  23:         Character state = null;

  24:  

  25:   for(int i = 0; i < length; i++)

  26:   {

  27:    state = new Character(compositeState.charAt(i) );

  28:             System.out.println("factory(" + state + ")");

  29:    compositeFly.add( state, this.factory( state) );

  30:   }

  31:   return compositeFly;

  32:     }

  33:  

  34:  public Flyweight factory(Character state)

  35:  {

  36:   if ( flies.containsKey( state ) )

  37:         {

  38:             return (Flyweight) flies.get( state );

  39:         }

  40:         else

  41:         {

  42:    Flyweight fly = new ConcreteFlyweight( state );

  43:             flies.put( state , fly);

  44:             return fly;

  45:         }

  46:  }

  47:  

  48:  public void checkFlyweight()

  49:  {

  50:   Flyweight fly ;

  51:         int i = 0 ;

  52:  

  53:         System.out.println("\n==========checkFlyweight()=============");

  54:   for ( Iterator it = flies.entrySet().iterator() ; it.hasNext() ;  )

  55:         {

  56:    Map.Entry e = (Map.Entry) it.next();

  57:             System.out.println( "Item " + (++i) + " : " + e.getKey());

  58:         }

  59:         System.out.println("\n==========checkFlyweight()=============");

  60:  }

  61:  

  62: }

  63:  

   1: //客户端(Client)角色

   2: public class Client

   3: {

   4:     private static FlyweightFactory factory;

   5:  

   6:     public static void main(String[] args)

   7:  {

   8:   factory = new FlyweightFactory();

   9:  

  10:   Flyweight fly;

  11: /*        fly = factory.factory(new Character('a'));

  12:   fly.operation();

  13:   

  14:   fly = factory.factory(new Character('b'));

  15:   fly.operation();

  16:   

  17:   fly = factory.factory(new Character('a'));

  18:   fly.operation();

  19: */

  20:         fly = factory.factory("abc");

  21:         fly.operation("Composite Call");

  22:   

  23: // intrinsic Flyweight

  24:   factory.checkFlyweight();

  25:  }

  26: }

  27:  

  28:  

  29:  

  30: