/**
* LOGBack: the reliable, fast and flexible logging library for Java.
*
* Copyright (C) 1999-2006, QOS.ch
*
* This library is free software, you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation.
*/
package ch.qos.logback.core.pattern;
import java.util.HashMap;
import java.util.Map;
import ch.qos.logback.core.Context;
import ch.qos.logback.core.LayoutBase;
import ch.qos.logback.core.pattern.parser.Node;
import ch.qos.logback.core.pattern.parser.Parser;
import ch.qos.logback.core.pattern.parser.ScanException;
import ch.qos.logback.core.spi.ContextAware;
import ch.qos.logback.core.status.ErrorStatus;
import ch.qos.logback.core.status.StatusManager;
abstract public class PatternLayoutBase extends LayoutBase {
Converter head;
String pattern;
Map<String, String> instanceConverterMap = new HashMap<String, String>();
/**
* Concrete implementations of this class are responsible for elaborating the
* mapping between pattern words and converters.
*
* @return A map associating pattern words to the names of converter classes
*/
abstract public Map<String, String> getDefaultConverterMap();
/**
* Returns a map where the default converter map is merged with the map
* contained in the context.
*/
public Map<String, String> getEffectiveConverterMap() {
Map<String, String> effectiveMap = new HashMap<String, String>();
// add the least specific map fist
Map<String, String> defaultMap = getDefaultConverterMap();
if (defaultMap != null) {
effectiveMap.putAll(defaultMap);
}
// contextMap is more specific than the default map
Context context = getContext();
if (context != null) {
Map<String, String> contextMap = context.getConverterMap();
if (contextMap != null) {
effectiveMap.putAll(contextMap);
}
}
// set the most specific map last
effectiveMap.putAll(instanceConverterMap);
return effectiveMap;
}
public void start() {
try {
Parser p = new Parser(pattern);
if (getContext() != null) {
p.setStatusManager(getContext().getStatusManager());
}
Node t = p.parse();
this.head = p.compile(t, getEffectiveConverterMap());
postCompileProcessing(head);
DynamicConverter.startConverters(this.head);
super.start();
} catch (ScanException sce) {
StatusManager sm = getContext().getStatusManager();
sm.add(new ErrorStatus("Failed to parse pattern \"" + getPattern()
+ "\".", this, sce));
}
}
/**
* Let derived classes perform postCompile processing. However, PatternLayout
* found in the classic module needs to add a converter for exception handling
* if there isn't one already.
*
* @param head
*/
protected void postCompileProcessing(Converter head) {
}
protected void setContextForConverters(Converter head) {
Context context = getContext();
Converter c = head;
while (c != null) {
if (c instanceof ContextAware) {
((ContextAware) c).setContext(context);
}
c = c.getNext();
}
}
protected String writeLoopOnConverters(Object event) {
StringBuffer buf = new StringBuffer(128);
Converter c = head;
while (c != null) {
c.write(buf, event);
c = c.getNext();
}
return buf.toString();
}
public String getPattern() {
return pattern;
}
public void setPattern(String pattern) {
this.pattern = pattern;
}
public String toString() {
return this.getClass().getName() + "(" + getPattern() + ")";
}
protected static Converter findTail(Converter head) {
Converter c = head;
while (c != null) {
Converter next = c.getNext();
if (next == null) {
break;
} else {
c = next;
}
}
return c;
}
public Map<String, String> getInstanceConverterMap() {
return instanceConverterMap;
}
}