log4j之全部保存

 

 如果是采用平时用的形如

log4j.appender.logfile.File=d:/log.txt
log4j.appender.logfile.MaxFileSize=1024KB
log4j.appender.logfile.MaxBackupIndex=4

则回出现一个问题,即只能保存一定数量的文件,在这里是只保存4个log文件,超过4个之后之前的信息就丢失了 ,但有时候 要求保留所有的log文件的时候这样的做法就无能为力了;这个时候就不能再用log4j.properties这个文件类配置了,而要用log4j.xml这个配置文件了;文件的大体形式如下:

<?xml version="1.0" encoding="UTF-8" ?>
  <!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
  <log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
    <!--
    <appender name="console" class="org.apache.log4j.ConsoleAppender">
      <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="%d %-5p %c - %m%n"/>
      </layout>
    </appender>
    -->
    <appender name="log" class="com.skywin.mps.crontab.tools.MpsTaskAppender">
      <param name="file" value="log/log.txt"/>
      <param name="MaxFileSize" value="1024KB"/>
      <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="%d %c - %m%n"/>
      </layout>
      <filter class="org.apache.log4j.varia.LevelMatchFilter">
        <param name="LevelToMatch" value="INFO"/>
      </filter>
      <filter class="org.apache.log4j.varia.DenyAllFilter"/>
    </appender>
    <appender name="trace" class="com.skywin.mps.crontab.tools.MpsTaskAppender">
      <param name="file" value="log/trace.txt"/>
      <param name="MaxFileSize" value="1024KB"/>
      <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="%d %c - %m%n"/>
      </layout>
      <filter class="org.apache.log4j.varia.LevelMatchFilter">
        <param name="LevelToMatch" value="DEBUG"/>
      </filter>
      <filter class="org.apache.log4j.varia.DenyAllFilter"/>
    </appender>
    <appender name="error" class="com.skywin.mps.crontab.tools.MpsTaskAppender">
      <param name="file" value="log/error.txt"/>
      <param name="MaxFileSize" value="1024KB"/>
      <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="%d %c - %m%n"/>
      </layout>
      <filter class="org.apache.log4j.varia.LevelMatchFilter">
        <param name="LevelToMatch" value="ERROR"/>
      </filter>
      <filter class="org.apache.log4j.varia.DenyAllFilter"/>
    </appender>
    <root>
      <appender-ref ref="error"/><appender-ref ref="log"/><appender-ref ref="trace"/></root>
  </log4j:configuration>

其中com.skywin.mps.crontab.tools.MpsTaskAppender是自己写的类

代码如下:

package com.skywin.mps.crontab.tools;

import java.io.File;
import java.io.IOException;
import java.util.Date;

import org.apache.log4j.RollingFileAppender;
import org.apache.log4j.helpers.CountingQuietWriter;
import org.apache.log4j.helpers.LogLog;

public class MpsTaskAppender extends RollingFileAppender {
	public void rollOver() {

		LogLog.debug("rolling over count=".concat(String.valueOf(String
				.valueOf(((CountingQuietWriter) super.qw).getCount()))));
		LogLog.debug("maxBackupIndex=".concat(String.valueOf(String
				.valueOf(super.maxBackupIndex))));
		int index = super.fileName.lastIndexOf('.');
		StringBuffer sb = new StringBuffer(super.fileName);
		sb.insert(index, getTimeExt());
		File target = new File(sb.toString());

		closeFile();
		File file = new File(super.fileName);
		LogLog
				.debug(String.valueOf(String.valueOf((new StringBuffer(
						"Renaming file ")).append(file).append(" to ").append(
						target))));
		file.renameTo(target);
		try {
			// setFile(super.fileName, false, super.bufferedIO,
			// super.bufferSize);
			setFile(super.fileName, true, super.bufferedIO, super.bufferSize);
		} catch (IOException e) {
			LogLog.error(String.valueOf(String.valueOf((new StringBuffer(
					"setFile(")).append(super.fileName).append(
					", false) call failed."))), e);
		}
	}

	private String getTimeExt() {
		String tstr = "_";
		// tstr = String.valueOf(tstr) + String.valueOf(StrDate.date2str(new
		// Date()));
		return tstr + PubTool.date2Str(new Date());
	}

	private String ext;

}