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Java > Open Source Codes > com > jcorporate > expresso > core > controller > DefaultControllerFactory


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64
65 package com.jcorporate.expresso.core.controller;
66
67 import com.jcorporate.expresso.core.misc.StringUtil;
68 import org.apache.oro.util.CacheLRU;
69
70
71 /**
72  * This version of Controller Factory acts dumb. If the controller hasn't
73  * been create already, it creates it. It is often used for Command Line
74  * operations where we don't use the Struts Action Servlet
75  *
76  * @author Michael Rimov
77  */
78 public class DefaultControllerFactory
79         implements ControllerFactory {
80
81     /**
82      * Class Instantiation. Stores the last 20 controllers created. Helps
83      * to keep down memory hogs for non-webserver systems.
84      */
85     protected CacheLRU controllerCache = new CacheLRU(20);
86
87     /**
88      * Do nothing constructor
89      */
90     public DefaultControllerFactory() {
91     }
92
93
94     /**
95      * Retrieve the Action controller that matches the class name
96      */
97     public synchronized Controller getController(String JavaDoc className)
98             throws ControllerException {
99         return getController("", className);
100     }
101
102     /**
103      * Retrieve the Action controller that matches the class name
104      * The <code>moduleName</code> is ignored for this implementation.
105      */
106     public synchronized Controller getController(String JavaDoc moduleName, String JavaDoc className)
107             throws ControllerException {
108         Controller c = (Controller) controllerCache.getElement(className);
109
110         if (c == null) {
111             c = Controller.instantiate(className);
112             controllerCache.addElement(className, c);
113         }
114
115         return c;
116     }
117
118     /**
119      * Retrieve the Action controller that matches the class name
120      * The Struts 1.1 modules are ignored for this implementation.
121      */
122     public synchronized Controller getController(ControllerRequest request)
123             throws ControllerException {
124         String JavaDoc s = request.getParameter(Controller.CONTROLLER_PARAM_KEY);
125         StringUtil.assertNotBlank(s,
126                 "You must define your controller " +
127                 "parameter in your controller request");
128
129         return getController(s);
130     }
131 }
132
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