如何使用AsyncAppender在log4j的？(How to use AsyncAppender

如何才能写日志消息给Web服务使用AsyncAppender在log4j的？我要创造我自己的Appender这将延长AsyncAppender或只是将自定义的appender到AsyncAppender？如果第二个选择是正确的，我应该在哪里拿AsyncAppender对象？是否有任何的例子吗？

Answer 1:

在log4j的配置文件，该文件将涉及到一个真正的appender添加AsyncAppender。对于演示：将asyncappender到的log4j.xml控制台的appender

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd" >
<log4j:configuration>
<appender name="console" class="org.apache.log4j.ConsoleAppender">
    <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="[%p] %d{dd MMM hh:mm:ss aa} %t [%l] %m%n"/>
    </layout>
</appender>
<appender name="async" class="org.apache.log4j.AsyncAppender">
    <param name="BufferSize" value="500"/>
    <appender-ref ref="console"/>
</appender>
<root>
    <priority value="all"></priority>
    <appender-ref ref="async"/>
</root>
</log4j:configuration>

Answer 2:

我们想用log4j.AsyncAppender，但找不到任何setter方法在log4j.property文件附加其他附加目的地。因此，我们扩展了log4j.AsyncAppender类并添加二传手添加其他附加目的地。这有助于主程序线程是独立的log4j的日志操作。下面的详细信息。

log4j的条目：

定义一个记录器“com.noPath”与log4j的文件追加程序，“fileAppender”。需要注意的是记录器路径是无关紧要的，故而得名“com.noPath”

log4j.logger.com.noPath=DEBUG,fileAppender
log4j.appender.fileAppender=org.apache.log4j.RollingFileAppender
log4j.appender.fileAppender.File=c:/test.log

通过延伸的log4j AsyncAppender自定义类com.log.AsyncAppenderHelper定义记录，企业的需求，“com.business”，附加上一步的文件附加目的地，“fileAppender”，将log4j AsyncAppender

log4j.logger.com.business=DEBUG,asyncLog
log4j.appender.asyncLog=com.log.AsyncAppenderHelper
log4j.appender.asyncLog.appenderFromLogger=com.noPath

Java类com.log.AsyncAppenderHelper延伸log4j.AsyncAppender，有它在类路径中可用。

package com.log
import java.util.Enumeration;
import org.apache.log4j.Appender;
import org.apache.log4j.AsyncAppender;
import org.apache.log4j.Logger;

/*
 * This class helps configure to AsyncAppender from log4j as part of log4j.properties
 * You can inject other appenders to AsyncAppender using the AsyncAppenderHelper
 * This would free up the main program thread to be independent of log4j's logging operation
 * @Author http://www.linkedin.com/in/jobypgeorge
 */

public class AsyncAppenderHelper extends AsyncAppender{

    public AsyncAppenderHelper(){
        super();
    }

    public void setAppenderFromLogger(String name){
        Logger l = Logger.getLogger(name);

        Enumeration<Appender> e = l.getAllAppenders();

        while(e.hasMoreElements()){
             Appender a = e.nextElement();
             this.addAppender(a);
             System.out.println("The newAppender "+a.getName() +" attach status "+this.isAttached(a));
        }

     }
}