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1   // 
2   // Copyright (c) 2003, Caltha - Gajda, Krzewski, Mach, Potempski Sp.J. 
3   // All rights reserved. 
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6   // are permitted provided that the following conditions are met: 
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8   // * Redistributions of source code must retain the above copyright notice,  
9   //   this list of conditions and the following disclaimer. 
10  // * Redistributions in binary form must reproduce the above copyright notice,  
11  //   this list of conditions and the following disclaimer in the documentation  
12  //   and/or other materials provided with the distribution. 
13  // * Neither the name of the Caltha - Gajda, Krzewski, Mach, Potempski Sp.J.  
14  //   nor the names of its contributors may be used to endorse or promote products  
15  //   derived from this software without specific prior written permission. 
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28  
29  package org.objectledge.pico.customization;
30  
31  import org.picocontainer.ComponentAdapter;
32  import org.picocontainer.PicoContainer;
33  import org.picocontainer.PicoInitializationException;
34  import org.picocontainer.PicoIntrospectionException;
35  import org.picocontainer.PicoVerificationException;
36  import org.picocontainer.PicoVisitor;
37  
38  /***
39   * An adapter for a component that is customized on behalf of a component that is asking for it.
40   * <p>
41   * When another component is being initialized and it depends on the component that is managed by
42   * this adapter (identified by the componentKey), the customizedContainerProvider is asked to
43   * produce an instance of the customized component. Thus, different components may recieve different
44   * instnaces of the managed component, depending on the customizedComponentProvider's semantics.
45   * </p>
46   * 
47   * @author <a href="Rafal.Krzewski">rafal@caltha.pl </a>
48   * @version $Id: CustomizedComponentAdapter.java,v 1.15 2005/02/04 02:28:00 rafal Exp $
49   */
50  public class CustomizedComponentAdapter
51      implements ComponentAdapter
52  {
53      private Object componentKey;
54  
55      private CustomizedComponentProvider customizedComponentProvider;
56  
57      /***
58       * Crates a new instance of the adapter.
59       * 
60       * @param componentKey the component key this adapter manages.
61       * @param customizedComponentProvider a provider of customized components.
62       */
63      public CustomizedComponentAdapter(Object componentKey,
64          CustomizedComponentProvider customizedComponentProvider)
65      {
66          this.componentKey = componentKey;
67          this.customizedComponentProvider = customizedComponentProvider;
68      }
69  
70      /***
71       * {@inheritDoc}
72       */
73      public Object getComponentInstance(PicoContainer container)
74          throws PicoInitializationException, PicoIntrospectionException
75      {
76          // lacking a better idea...
77          return customizedComponentProvider.getCustomizedComponentInstance(container, null, null);
78      }
79  
80      /***
81       * Returns a customized components instance.
82       * <p>
83       * This method is called by the {@link CustomizingConstructorComponentAdapter}.
84       * </p>
85       * 
86       * @param container the container for resolving references.
87       * @param componentKey the key of the requesting component.
88       * @param componentImplementation the implemenation class of the requesting component.
89       * @return a customized component instance.
90       * @throws PicoInitializationException if the customized component cannot be instantiated.
91       * @throws PicoIntrospectionException if there is a problem introspecting classes.
92       * @throws UnsupportedKeyTypeException if the requesting component key if an unsupported type.
93       */
94      public Object getComponentInstance(PicoContainer container, Object componentKey,
95          Class componentImplementation)
96          throws PicoInitializationException, PicoIntrospectionException, UnsupportedKeyTypeException
97      {
98          return customizedComponentProvider.getCustomizedComponentInstance(container, componentKey,
99              componentImplementation);
100     }
101 
102     /***
103      * {@inheritDoc}
104      */
105     public void verify(PicoContainer container)
106         throws PicoVerificationException
107     {
108         customizedComponentProvider.verify(container);
109     }
110 
111     /***
112      * {@inheritDoc}
113      */
114     public Class getComponentImplementation()
115     {
116         return customizedComponentProvider.getCustomizedComponentImplementation();
117     }
118 
119     /***
120      * {@inheritDoc}
121      */
122     public Object getComponentKey()
123     {
124         return componentKey;
125     }
126 
127     /***
128      * {@inheritDoc}
129      */
130     public void accept(PicoVisitor visitor)
131     {
132         visitor.visitComponentAdapter(this);
133     }
134 }