001    /*
002     * Copyright 2004-2005 Stephen J. McConnell.
003     *
004     * Licensed  under the  Apache License,  Version 2.0  (the "License");
005     * you may not use  this file  except in  compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     *   http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed  under the  License is distributed on an "AS IS" BASIS,
012     * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY KIND, either  express  or
013     * implied.
014     *
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package net.dpml.util;
020    
021    /**
022     * Transit Logger is a interface through which different logging solutions
023     * can be provided.
024     *
025     * @author <a href="http://www.dpml.net">Digital Product Meta Library</a>
026     * @version 1.0.1
027     */
028    public interface Logger
029    {
030       /**
031        * Return TRUE is trace level logging is enabled.
032        * @return the enabled state of trace logging
033        */
034        boolean isTraceEnabled();
035    
036       /**
037        * Return TRUE is debug level logging is enabled.
038        * @return the enabled state of debug logging
039        */
040        boolean isDebugEnabled();
041    
042       /**
043        * Return TRUE is info level logging is enabled.
044        * @return the enabled state of info logging
045        */
046        boolean isInfoEnabled();
047    
048       /**
049        * Return TRUE is warn level logging is enabled.
050        * @return the enabled state of warn level logging
051        */
052        boolean isWarnEnabled();
053    
054       /**
055        * Return TRUE is error level logging is enabled.
056        * @return the enabled state of error logging
057        */
058        boolean isErrorEnabled();
059    
060       /**
061        * Record a trace level message.
062        * @param message the trace message to record
063        */
064        void trace( String message );
065    
066       /**
067        * Record a debug level message.
068        * @param message the debug message to record
069        */
070        void debug( String message );
071    
072       /**
073        * Record a informative message.
074        * @param message the info message to record
075        */
076        void info( String message );
077    
078       /**
079        * Record a warning message.
080        * @param message the warning message to record
081        */
082        void warn( String message );
083    
084       /**
085        * Record a warning message.
086        * @param message the warning message to record
087        * @param cause the causal exception
088        */
089        void warn( String message, Throwable cause );
090    
091       /**
092        * Record a error level message.
093        * @param message the error message to record
094        */
095        void error( String message );
096    
097       /**
098        * Record a error level message.
099        * @param message the error message to record
100        * @param cause the causal exception
101        */
102        void error( String message, Throwable cause );
103    
104       /**
105        * Return a child logger relative to the current logger.
106        * @param category the relative category name
107        * @return the child logging channel
108        */
109        Logger getChildLogger( String category );
110    }
111    
112