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Java > Open Source Codes > org > apache > commons > discovery > resource > classes > DiscoverClasses


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57
58 package org.apache.commons.discovery.resource.classes;
59
60 import java.net.URL JavaDoc;
61 import java.util.Vector JavaDoc;
62
63 import org.apache.commons.discovery.ResourceClass;
64 import org.apache.commons.discovery.ResourceClassDiscover;
65 import org.apache.commons.discovery.ResourceNameListener;
66 import org.apache.commons.discovery.log.DiscoveryLogFactory;
67 import org.apache.commons.discovery.resource.ClassLoaders;
68 import org.apache.commons.logging.Log;
69
70
71 /**
72  * The findResources() method will check every loader.
73  *
74  * @author Richard A. Sitze
75  * @author Craig R. McClanahan
76  * @author Costin Manolache
77  * @author James Strachan
78  */
79 public class DiscoverClasses extends ResourceClassDiscoverImpl
80     implements ResourceClassDiscover, ResourceNameListener
81 {
82     private static Log log = DiscoveryLogFactory.newLog(DiscoverClasses.class);
83     public static void setLog(Log _log) {
84         log = _log;
85     }
86
87     /** Construct a new resource discoverer
88      */
89     public DiscoverClasses() {
90         super();
91     }
92     
93     /** Construct a new resource discoverer
94      */
95     public DiscoverClasses(ClassLoaders classLoaders) {
96         super(classLoaders);
97     }
98     
99     public boolean find(String JavaDoc className) {
100         final String JavaDoc resourceName = className.replace('.','/') + ".class";
101         
102         if (log.isDebugEnabled())
103             log.debug("find: className='" + className + "'");
104
105         Vector JavaDoc history = new Vector JavaDoc();
106
107         for (int idx = 0; idx < getClassLoaders().size(); idx++) {
108             ClassLoader JavaDoc loader = getClassLoaders().get(idx);
109             URL JavaDoc url = loader.getResource(resourceName);
110             if (url != null) {
111                 if (!history.contains(url)) {
112                     history.addElement(url);
113                     if (!notifyListener(new ResourceClass(className,
114                                                           url,
115                                                           loader)))
116                         return false;
117                 } else {
118                     if (log.isDebugEnabled())
119                         log.debug("find: duplicate URL='" + url + "'");
120                 }
121             } else {
122                 if (log.isDebugEnabled())
123                     log.debug("find: '" + resourceName + "' not found with loader: " + loader);
124             }
125         }
126         
127         return true;
128     }
129     
130     public boolean found(String JavaDoc className) {
131         return find(className);
132     }
133 }
134
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