Apache Log4j 2是Log4j的升级版,它比Log4j 1.x 版本有了很大的性能提升,吸收了LogBack的先进功能,更通过优秀的锁机制、LMAX Disruptor、"无垃圾"机制等先进特性,在性能上全面超越了Log4j和LogBack
升级Log4j2后的项目地址:
https://github.com/ryiann/ssm-dubbo
为什么升级Log4j2,有哪些优点?
- 日志模板功能
- 支持异步输出日志
- 略…具体请查看官方文档
好了,本文的重点也不是介绍Log4j2的优点,本文主要记录下Dubbo框架升级Log4j2的一些坑,所以这里不介绍那么多了
之前使用dubbo框架采用的是log4j日志,自从知道了log4j2的优秀日志模板,在写法上有了改进,就一直念念不忘,今天花了点时间把日志升了下级,不过也遇到了一些坑,升级后,出现log4j、log4j2冲突问题,控制台一直出现以下WARN,一些日志打印不出来
Zookeeper/ZkClient等默认使用log4j的组件无法打印日志
log4j:WARN No appenders could be found for logger (org.springframework.web.context.ContextLoader).
解决
###导入log4j2依赖
按实际情况引入桥接,如果没有使用commons-logging日志,就不用引入log4j-jcl
,博主没有引入
<!-- 桥接:告诉Slf4j使用Log4j2 -->
<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-slf4j-impl -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.8.2</version>
</dependency>
<!-- 桥接:告诉commons-logging使用Log4j2 -->
<!--<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-jcl</artifactId>
<version>2.8.2</version>
</dependency>-->
<!-- log4j2 api -->
<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-api -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.8.2</version>
</dependency>
<!-- log4j2 core -->
<!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-core -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.8.2</version>
</dependency>
排除非log4j2日志的依赖
<!-- dubbo -->
<!-- https://mvnrepository.com/artifact/com.alibaba/dubbo -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>dubbo</artifactId>
<version>2.5.3</version>
<exclusions>
<exclusion>
<artifactId>spring</artifactId>
<groupId>org.springframework</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper</artifactId>
<version>3.4.6</version>
<exclusions>
<!-- 排除log4j1的方式 -->
<exclusion>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
</exclusion>
<!-- 排除logback的方式 -->
<exclusion>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
</exclusion>
</exclusions>
</dependency>
<!-- zkclient -->
<!-- https://mvnrepository.com/artifact/com.101tec/zkclient -->
<dependency>
<groupId>com.101tec</groupId>
<artifactId>zkclient</artifactId>
<version>0.10</version>
</dependency>
编译项目、运行,飞起… Over