升级之后程序里的日志记录代码不需要更改，实验证明log4j2比log4j效率更高
1、引入官方log4j2 相关资源，maven依赖如下
2、resource目录下增加log4j2.xml文件
3、自定义的layout类，可以根据自己需要改写
package com.bbk.watch.store.common.log4j;
importjava.io.PrintWriter;
importjava.io.StringWriter;
importjava.io.Writer;
import java.nio.charset.Charset;
import java.util.Date;
import org.apache.commons.lang.exception.ExceptionUtils;
import org.apache.logging.log4j.core.LogEvent;
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.PluginFactory;
import org.apache.logging.log4j.core.layout.AbstractStringLayout;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.bbk.watch.store.common.ElkLog;
import com.bbk.watch.store.common.ResponseUtils;
import com.bbk.watch.store.common.ResultBeanFactory;
@Plugin(name = "SampleLayout", category = "Core", elementType = "layout", printObject = true)
public class SampleLayout extends AbstractStringLayout {
/**
*
*/
private static final long serialVersionUID = 1L;
protected SampleLayout(boolean locationInfo, boolean properties, boolean complete,
Charset charset) {
super(charset);
}
@PluginFactory
public static SampleLayout createLayout(@PluginAttribute("locationInfo") boolean locationInfo,
@PluginAttribute("properties") boolean properties,
@PluginAttribute("complete") boolean complete,
@PluginAttribute(value = "charset", defaultString = "UTF-8") Charset charset) {
return new SampleLayout(locationInfo, properties, complete, charset);
}
@Override
public String toSerializable(LogEvent loggingEvent) {
if (loggingEvent.getMessage().getParameters() == null || loggingEvent.getMessage().getParameters().length == 0) {
return String.format("[%s] [%s] %s", "elk",
ResponseUtils.formatDate(new Date()), "不能解析的日志类型" + "\n");
}
StringBuilder exceptionBuiler = new StringBuilder();
Object object = loggingEvent.getMessage().getParameters()[0];
// if
// (DaLog.class.isAssignableFrom(loggingEvent.getMessage().getClass()))
// {
// return StringUtils.EMPTY;
// }
JSONObject logstashEvent = new JSONObject();
if (loggingEvent.getThrown() != null) {
final Throwable throwableInformation = loggingEvent.getThrown();
try {
Writer w = new StringWriter();
throwableInformation.printStackTrace(new PrintWriter(w));
exceptionBuiler.append(w.toString());
} catch (Exception e) {
}
} else if ("ERROR".equals(loggingEvent.getLevel().toString())) {
if (object instanceof Exception) {
Exception exception = (Exception) object;
String stackTrace = ExceptionUtils.getFullStackTrace(exception);
exceptionBuiler.append(stackTrace);
}
}
if (loggingEvent.isIncludeLocation()) {
StackTraceElement stackTraceElement = loggingEvent.getSource();
logstashEvent.put("exceptionName",
String.format("%s %s %s", stackTraceElement.getClassName(), stackTraceElement.getMethodName(), stackTraceElement.getLineNumber()));
}
logstashEvent.put("exceptionLevel", loggingEvent.getLevel().toString());
if (String.class.isAssignableFrom(object.getClass())) {
exceptionBuiler.append(object);
} else if (ElkLog.class.isAssignableFrom(object.getClass())) {
ElkLog elkLog = (ElkLog) object;
exceptionBuiler.append(elkLog.getException());
logstashEvent.put("code", elkLog.getCode());
logstashEvent.put("desc", elkLog.getDesc());
} else if (Exception.class.isAssignableFrom(object.getClass())) {
Exception exception = (Exception) object;
exceptionBuiler.append(ExceptionUtils.getFullStackTrace(exception));
logstashEvent.put("code", ResultBeanFactory.FAIL_CODE);
} else {
}
logstashEvent.put("exception", exceptionBuiler.toString());
return String.format("[%s] [%s] %s", "elk",
ResponseUtils.formatDate(new Date()), JSON.toJSONString(logstashEvent) + "\n");
}
}
4、去掉web.xml log4j1.x相关配置，这里tomcat启动日志不会输出到文件，如果需要可以参考官网http://logging.apache.org/log4j/2.x/manual/webapp.html，没对这一部分进行研究。
