001    /*****************************************************************************
002     * Copyright (C) PicoContainer Organization. All rights reserved.            *
003     * ------------------------------------------------------------------------- *
004     * The software in this package is published under the terms of the BSD      *
005     * style license a copy of which has been included with this distribution in *
006     * the LICENSE.txt file.                                                     *
007     *                                                                           *
008     * Original code by Paul Hammant                                             *
009     *****************************************************************************/
010    
011    package org.picocontainer.gems.monitors;
012    
013    import static org.picocontainer.monitors.ComponentMonitorHelper.ctorToString;
014    import static org.picocontainer.monitors.ComponentMonitorHelper.format;
015    import static org.picocontainer.monitors.ComponentMonitorHelper.memberToString;
016    import static org.picocontainer.monitors.ComponentMonitorHelper.methodToString;
017    import static org.picocontainer.monitors.ComponentMonitorHelper.parmsToString;
018    
019    import java.io.IOException;
020    import java.io.ObjectInputStream;
021    import java.io.ObjectOutputStream;
022    import java.io.Serializable;
023    import java.lang.reflect.Constructor;
024    import java.lang.reflect.Member;
025    import java.lang.reflect.Method;
026    
027    import org.apache.log4j.LogManager;
028    import org.apache.log4j.Logger;
029    import org.apache.log4j.Priority;
030    import org.picocontainer.ComponentAdapter;
031    import org.picocontainer.ComponentMonitor;
032    import org.picocontainer.MutablePicoContainer;
033    import org.picocontainer.PicoContainer;
034    import org.picocontainer.Injector;
035    import org.picocontainer.Behavior;
036    import org.picocontainer.monitors.ComponentMonitorHelper;
037    import org.picocontainer.monitors.NullComponentMonitor;
038    
039    
040    /**
041     * A {@link org.picocontainer.ComponentMonitor} which writes to a Log4J {@link org.apache.log4j.Logger} instance.
042     * The Logger instance can either be injected or, if not set, the {@link LogManager LogManager}
043     * will be used to retrieve it at every invocation of the monitor.
044     *
045     * @author Paul Hammant
046     * @author Mauro Talevi
047     */
048    @SuppressWarnings("serial")
049    public class Log4JComponentMonitor implements ComponentMonitor, Serializable {
050    
051    
052            /**
053             * Log4j Logger.
054             */
055        private transient Logger logger;
056        
057        /**
058         * Delegate Monitor.
059         */
060        private final ComponentMonitor delegate;
061    
062        /**
063         * Creates a Log4JComponentMonitor with no Logger instance set.
064         * The {@link LogManager LogManager} will be used to retrieve the Logger instance
065         * at every invocation of the monitor.
066         */
067        public Log4JComponentMonitor() {
068            delegate = new NullComponentMonitor();
069            
070        }
071        
072        /**
073         * Creates a Log4JComponentMonitor with a given Logger instance class.
074         * The class name is used to retrieve the Logger instance.
075         *
076         * @param loggerClass the class of the Logger
077         */
078        public Log4JComponentMonitor(final Class<?> loggerClass) {
079            this(loggerClass.getName());
080        }
081    
082        /**
083         * Creates a Log4JComponentMonitor with a given Logger instance name. It uses the
084         * {@link org.apache.log4j.LogManager LogManager} to create the Logger instance.
085         *
086         * @param loggerName the name of the Log
087         */
088        public Log4JComponentMonitor(final String loggerName) {
089            this(LogManager.getLogger(loggerName));
090        }
091    
092        /**
093         * Creates a Log4JComponentMonitor with a given Logger instance
094         *
095         * @param logger the Logger to write to
096         */
097        public Log4JComponentMonitor(final Logger logger) {
098            this();
099            this.logger = logger;
100        }
101    
102        /**
103         * Creates a Log4JComponentMonitor with a given Logger instance class.
104         * The class name is used to retrieve the Logger instance.
105         *
106         * @param loggerClass the class of the Logger
107         * @param delegate the delegate
108         */
109        public Log4JComponentMonitor(final Class<?> loggerClass, final ComponentMonitor delegate) {
110            this(loggerClass.getName(), delegate);
111        }
112    
113        /**
114         * Creates a Log4JComponentMonitor with a given Logger instance name. It uses the
115         * {@link org.apache.log4j.LogManager LogManager} to create the Logger instance.
116         *
117         * @param loggerName the name of the Log
118         * @param delegate the delegate
119         */
120        public Log4JComponentMonitor(final String loggerName, final ComponentMonitor delegate) {
121            this(LogManager.getLogger(loggerName), delegate);
122        }
123    
124        /**
125         * Creates a Log4JComponentMonitor with a given Logger instance
126         *
127         * @param logger the Logger to write to
128         * @param delegate the delegate
129         */
130        public Log4JComponentMonitor(final Logger logger, final ComponentMonitor delegate) {
131            this(delegate);
132            this.logger = logger;
133        }
134    
135        public Log4JComponentMonitor(final ComponentMonitor delegate) {
136            this.delegate = delegate;
137        }
138    
139        /** {@inheritDoc} **/
140        public <T> Constructor<T> instantiating(final PicoContainer container, final ComponentAdapter<T> componentAdapter,
141                                         final Constructor<T> constructor
142        ) {
143            Logger logger = getLogger(constructor);
144            if (logger.isDebugEnabled()) {
145                logger.debug(format(ComponentMonitorHelper.INSTANTIATING, ctorToString(constructor)));
146            }
147            return delegate.instantiating(container, componentAdapter, constructor);
148        }
149    
150        /** {@inheritDoc} **/
151        public <T> void instantiated(final PicoContainer container, final ComponentAdapter<T> componentAdapter,
152                                 final Constructor<T> constructor,
153                                 final Object instantiated,
154                                 final Object[] parameters,
155                                 final long duration) {
156            Logger logger = getLogger(constructor);
157            if (logger.isDebugEnabled()) {
158                logger.debug(format(ComponentMonitorHelper.INSTANTIATED, ctorToString(constructor), duration, instantiated.getClass().getName(), parmsToString(parameters)));
159            }
160            delegate.instantiated(container, componentAdapter, constructor, instantiated, parameters, duration);
161        }
162    
163        /** {@inheritDoc} **/
164        public <T> void instantiationFailed(final PicoContainer container,
165                                        final ComponentAdapter<T> componentAdapter,
166                                        final Constructor<T> constructor,
167                                        final Exception cause) {
168            Logger logger = getLogger(constructor);
169            if (logger.isEnabledFor(Priority.WARN)) {
170                logger.warn(format(ComponentMonitorHelper.INSTANTIATION_FAILED, ctorToString(constructor), cause.getMessage()), cause);
171            }
172            delegate.instantiationFailed(container, componentAdapter, constructor, cause);
173        }
174    
175        /** {@inheritDoc} **/
176        public void invoking(final PicoContainer container,
177                             final ComponentAdapter<?> componentAdapter,
178                             final Member member,
179                             final Object instance) {
180            Logger logger = getLogger(member);
181            if (logger.isDebugEnabled()) {
182                logger.debug(format(ComponentMonitorHelper.INVOKING, memberToString(member), instance));
183            }
184            delegate.invoking(container, componentAdapter, member, instance);
185        }
186    
187        /** {@inheritDoc} **/
188        public void invoked(final PicoContainer container,
189                            final ComponentAdapter<?> componentAdapter,
190                            final Method method,
191                            final Object instance,
192                            final long duration) {
193            Logger logger = getLogger(method);
194            if (logger.isDebugEnabled()) {
195                logger.debug(format(ComponentMonitorHelper.INVOKED, methodToString(method), instance, duration));
196            }
197            delegate.invoked(container, componentAdapter, method, instance, duration);
198        }
199    
200        /** {@inheritDoc} **/
201        public void invocationFailed(final Member member, final Object instance, final Exception cause) {
202            Logger logger = getLogger(member);
203            if (logger.isEnabledFor(Priority.WARN)) {
204                logger.warn(format(ComponentMonitorHelper.INVOCATION_FAILED, memberToString(member), instance, cause.getMessage()), cause);
205            }
206            delegate.invocationFailed(member, instance, cause);
207        }
208    
209        /** {@inheritDoc} **/
210        public void lifecycleInvocationFailed(final MutablePicoContainer container,
211                                              final ComponentAdapter<?> componentAdapter, final Method method,
212                                              final Object instance,
213                                              final RuntimeException cause) {
214            Logger logger = getLogger(method);
215            if (logger.isEnabledFor(Priority.WARN)) {
216                logger.warn(format(ComponentMonitorHelper.LIFECYCLE_INVOCATION_FAILED, methodToString(method), instance, cause.getMessage()), cause);
217            }
218            delegate.lifecycleInvocationFailed(container, componentAdapter, method, instance, cause);
219        }
220    
221        /** {@inheritDoc} **/
222        public Object noComponentFound(final MutablePicoContainer container, final Object componentKey) {
223            Logger logger = this.logger != null ? this.logger : LogManager.getLogger(ComponentMonitor.class);
224            if (logger.isEnabledFor(Priority.WARN)) {
225                logger.warn(format(ComponentMonitorHelper.NO_COMPONENT, componentKey));
226            }
227            return delegate.noComponentFound(container, componentKey);
228    
229        }
230    
231        /** {@inheritDoc} */
232        public Injector newInjector(final Injector injector) {
233            return delegate.newInjector(injector);
234        }
235    
236        /** {@inheritDoc} **/
237        public Behavior newBehavior(Behavior behavior) {
238            return delegate.newBehavior(behavior);
239        }
240    
241        protected Logger getLogger(final Member member) {
242            if ( logger != null ){
243                return logger;
244            } 
245            return LogManager.getLogger(member.getDeclaringClass());
246        }
247    
248        
249        /**
250         * Serializes the monitor.
251         * @param oos object output stream.
252         * @throws IOException
253         */
254        private void writeObject(final ObjectOutputStream oos) throws IOException {
255            oos.defaultWriteObject();
256            if (logger != null) {
257                    oos.writeBoolean(true);
258                    oos.writeUTF(logger.getName());
259            } else {
260                    oos.writeBoolean(false);                        
261            }
262        }
263        
264        /**
265         * Manually creates a new logger instance if it was defined earlier.
266         * @param ois
267         * @throws IOException
268         * @throws ClassNotFoundException
269         */
270        private void readObject(final ObjectInputStream ois) throws IOException, ClassNotFoundException {
271            ois.defaultReadObject();
272            boolean hasDefaultLogger = ois.readBoolean();
273            if (hasDefaultLogger) {
274                    String defaultLoggerCategory = ois.readUTF();
275                    assert defaultLoggerCategory != null : "Serialization indicated default logger, "
276                            +"but no logger category found in input stream.";
277                    logger = LogManager.getLogger(defaultLoggerCategory);
278            }
279        }
280    
281    }