Question

我正在尝试转换之前在log4j 1.x中使用AppenderSkeleton编写的类，现在我正在尝试将我的服务迁移到log4j 2.6。

代码：

package com.amazon.digital.music.purchasing.scheduler.test;

import java.util.ArrayList;
import java.util.List;

import org.apache.log4j.AppenderSkeleton;
import org.apache.log4j.Logger;
import org.apache.log4j.spi.LoggingEvent;

/**
 * A log appender which collects the log messages.
 * Automatically appends itself to the root logger.
 * 
 */
 class LogMessagesCollector extends AppenderSkeleton {
 private final List<String> messages = new ArrayList<String>();

 public LogMessagesCollector() {
     final Logger logger = Logger.getRootLogger();
     logger.addAppender(this);
 }

 @Override
 public boolean requiresLayout() {
     return false;
 }

 @Override
 protected void append(final LoggingEvent loggingEvent) {
     messages.add(loggingEvent.getMessage().toString());
 }

 @Override
 public void close() {
     final Logger logger = Logger.getRootLogger();
     logger.removeAppender(this);
 }

 public List<String> getMessages() {
     return messages;
 }

我按照链接： How to Create a Custom Appender in log4j2?了解如何在log4j2中编写自定义appender，但无法编写可替换此类的类。

任何帮助都会很棒。谢谢！

Answer 1

请查看log4j-core模块的单元测试中的ListAppender。它的类似之处在于它收集列表中的日志事件。它还有一些其他功能可以方便测试，但它可以成为自定义appender的一个很好的模板。

Answer 2

遇到同样的问题。这是自定义解决方案的模板

log4j2.properties

name = PropertiesConfig
property.filename = logs
appenders =  basic

appender.basic.type = Basic
appender.basic.name = Basic
appender.basic.layout.type= PatternLayout
appender.basic.layout.pattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

rootLogger.level = debug
rootLogger.appenderRefs = flume
rootLogger.appenderRef.flume.ref = Basic

BasicAppender.java

import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.Layout;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.appender.AbstractAppender;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.core.layout.PatternLayout;

import java.io.Serializable;

@Plugin(name = "Basic", category = "Core", elementType = "appender", printObject = true)
public class BasicAppender extends AbstractAppender {

    private static volatile BasicAppender instance;

    public BasicAppender(final String name, final Filter filter, final Layout<? extends Serializable> layout){
        super(name, filter, layout);
    }

    @PluginFactory
    public static BasicAppender createAppender(@PluginAttribute("name") String name,
                                               @PluginElement("Layout") Layout layout,
                                               @PluginElement("Filters") Filter filter){
        if (layout == null){
            layout = PatternLayout.createDefaultLayout();
        }
        return new BasicAppender(name, filter, layout);
    }

    public static BasicAppender getInstance(){
        return instance;
    }

    @Override
    public void append(final LogEvent event){
        //custom actions
    }
}

从Log4j 1.x迁移到Log4j2

2 个答案: