org.apache.log4j.pattern.LoggingEventPatternConverter Maven / Gradle / Ivy
/*
* 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.
*/
package org.apache.log4j.pattern;
import org.apache.log4j.spi.LoggingEvent;
/**
* LoggingEventPatternConverter is a base class for pattern converters
* that can format information from instances of LoggingEvent.
*
* @author Curt Arnold
*
*/
public abstract class LoggingEventPatternConverter extends PatternConverter {
/**
* Constructs an instance of LoggingEventPatternConverter.
* @param name name of converter.
* @param style CSS style for output.
*/
protected LoggingEventPatternConverter(
final String name, final String style) {
super(name, style);
}
/**
* Formats an event into a string buffer.
* @param event event to format, may not be null.
* @param toAppendTo string buffer to which the formatted event will be appended. May not be null.
*/
public abstract void format(
final LoggingEvent event, final StringBuffer toAppendTo);
/**
* {@inheritDoc}
*/
public void format(final Object obj, final StringBuffer output) {
if (obj instanceof LoggingEvent) {
format((LoggingEvent) obj, output);
}
}
/**
* Normally pattern converters are not meant to handle Exceptions although
* few pattern converters might.
*
* By examining the return values for this method, the containing layout will
* determine whether it handles throwables or not.
* @return true if this PatternConverter handles throwables
*/
public boolean handlesThrowable() {
return false;
}
}