Java tutorial
package org.apache.velocity.tools.generic.log; /* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ import org.apache.velocity.app.Velocity; import org.apache.velocity.runtime.log.Log; /** * Redirects commons-logging messages to Velocity's configured LogChute. * * <p>To use, specify this class in your commons-logging.properties: * <pre><code> * org.apache.commons.logging.Log=org.apache.velocity.tools.generic.log.LogChuteCommonsLog * </code></pre> * </p> * @since VelocityTools 2.0 * @version $Id: LogChuteCommonsLog.java 72115 2004-11-11 07:00:54Z nbubna $ */ public class LogChuteCommonsLog implements org.apache.commons.logging.Log { private static Log target = null; /** * Allow subclasses to statically access the static target. */ protected static Log getVelocityLog() { return target; } /** * Set a VelocityEngine to handle all the log messages. */ public static void setVelocityLog(Log target) { LogChuteCommonsLog.target = target; } // ******************** begin non-static stuff ******************* private String category; public LogChuteCommonsLog() { this(""); } public LogChuteCommonsLog(String category) { this.category = category + ": "; } protected Log getTarget() { if (target == null) { return Velocity.getLog(); } else { return target; } } /*************** Commons Log Interface ****************/ /** * Passes messages to Velocity's LogChute at "DEBUG" level. * (it's the lowest available. sorry.) */ public void trace(Object message) { getTarget().trace(category + message); } /** * Passes messages to Velocity's LogChute at "DEBUG" level. * (it's the lowest available. sorry.) */ public void trace(Object message, Throwable t) { getTarget().trace(category + message, t); } /** * Passes messages to Velocity's LogChute at "DEBUG" level. */ public void debug(Object message) { getTarget().debug(category + message); } /** * Passes messages to Velocity's LogChute at "DEBUG" level. */ public void debug(Object message, Throwable t) { getTarget().debug(category + message, t); } /** * Passes messages to Velocity's LogChute at "INFO" level. */ public void info(Object message) { getTarget().info(category + message); } /** * Passes messages to Velocity's LogChute at "INFO" level. */ public void info(Object message, Throwable t) { getTarget().info(category + message, t); } /** * Passes messages to Velocity's LogChute at "WARN" level. */ public void warn(Object message) { getTarget().warn(category + message); } /** * Passes messages to Velocity's LogChute at "WARN" level. */ public void warn(Object message, Throwable t) { getTarget().warn(category + message, t); } /** * Passes messages to Velocity's LogChute at "ERROR" level. */ public void error(Object message) { getTarget().error(category + message); } /** * Passes messages to Velocity's LogChute at "ERROR" level. */ public void error(Object message, Throwable t) { getTarget().error(category + message, t); } /** * Passes messages to Velocity's LogChute at "ERROR" level. * (it's the highest available. sorry.) */ public void fatal(Object message) { getTarget().error(category + message); } /** * Passes messages to Velocity's LogChute at "ERROR" level. * (it's the highest available. sorry.) */ public void fatal(Object message, Throwable t) { getTarget().error(category + message, t); } /** * Returns true if Velocity's LogChute returns true * for isTraceEnabled(). */ public boolean isTraceEnabled() { return getTarget().isTraceEnabled(); } /** * Returns true if Velocity's LogChute returns true * for isDebugEnabled(). */ public boolean isDebugEnabled() { return getTarget().isDebugEnabled(); } /** * Returns true if Velocity's LogChute returns true * for isInfoEnabled(). */ public boolean isInfoEnabled() { return getTarget().isInfoEnabled(); } /** * Returns true if Velocity's LogChute returns true * for isWarnEnabled(). */ public boolean isWarnEnabled() { return getTarget().isWarnEnabled(); } /** * Returns true if Velocity's LogChute returns true * for isErrorEnabled(). */ public boolean isErrorEnabled() { return getTarget().isErrorEnabled(); } /** * Returns true if isErrorEnabled() returns true, since * Velocity's LogChute doesn't support this level. */ public boolean isFatalEnabled() { return isErrorEnabled(); } }