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1
61
62
63 package org.apache.commons.discovery.log;
64
65 import java.lang.reflect.Method  ;
66 import java.lang.reflect.Modifier ;
67 import java.util.Enumeration ;
68 import java.util.Hashtable ;
69
70 import org.apache.commons.discovery.DiscoveryException;
71 import org.apache.commons.discovery.tools.ClassUtils;
72 import org.apache.commons.logging.Log;
73 import org.apache.commons.logging.LogFactory;
74
75
76
97 public class DiscoveryLogFactory {
98 private static LogFactory logFactory = null;
99 private static final Hashtable classRegistry = new Hashtable ();
100 private static final Class [] setLogParamClasses = new Class [] { Log.class };
101
102
105 private static Log log = DiscoveryLogFactory._newLog(DiscoveryLogFactory.class);
106
107
109 public static Log newLog(Class clazz) {
110
113 try {
114 Method setLog = ClassUtils.findPublicStaticMethod(clazz,
115 void.class,
116 "setLog",
117 setLogParamClasses);
118
119 if (setLog == null) {
120 String msg = "Internal Error: " + clazz.getName() + " required to implement 'public static void setLog(Log)'";
121 log.fatal(msg);
122 throw new DiscoveryException(msg);
123 }
124 } catch (SecurityException se) {
125 String msg = "Required Security Permissions not present";
126 log.fatal(msg, se);
127 throw new DiscoveryException(msg, se);
128 }
129
130 if (log.isDebugEnabled())
131 log.debug("Class meets requirements: " + clazz.getName());
132
133 return _newLog(clazz);
134 }
135
136
139 public static Log _newLog(Class clazz) {
140 classRegistry.put(clazz, clazz);
141
142 return (logFactory == null)
143 ? new SimpleLog(clazz.getName())
144 : logFactory.getInstance(clazz.getName());
145 }
146
147 public static void setLog(Log _log) {
148 log = _log;
149 }
150
151
154 public static void setFactory(LogFactory factory) {
155 if (logFactory == null) {
156 logFactory = factory;
158
159 Enumeration elements = classRegistry.elements();
161 while (elements.hasMoreElements()) {
162 Class clazz = (Class )elements.nextElement();
163
164 if (log.isDebugEnabled())
165 log.debug("Reset Log for: " + clazz.getName());
166
167 Method setLog = null;
168
169 try {
172 setLog = clazz.getMethod("setLog", setLogParamClasses);
173 } catch(Exception e) {
174 String msg = "Internal Error: pre-check for " + clazz.getName() + " failed?!";
175 log.fatal(msg, e);
176 throw new DiscoveryException(msg, e);
177 }
178
179 Object [] setLogParam = new Object [] { factory.getInstance(clazz.getName()) };
180
181 try {
182 setLog.invoke(null, setLogParam);
183 } catch(Exception e) {
184 String msg = "Internal Error: setLog failed for " + clazz.getName();
185 log.fatal(msg, e);
186 throw new DiscoveryException(msg, e);
187 }
188 }
189 }
190 }
191 }
192 |
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