【转】SLF4J整合log4j

一，引入jar

maven 项目中,只需要引入下面的dependency

<dependency>  
    <groupId>org.slf4j</groupId>  
    <artifactId>slf4j-log4j12</artifactId>  
    <version>1.7.2</version>  
</dependency>

二、配置log4j.properties

因为log4j是具体的实现框架，需要配置log4j.properties

# rootLogger参数分别为：根Logger级别，输出器stdout，输出器log
log4j.rootLogger = info,stdout,log

# 输出信息到控制台
log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern = %d [%-5p] %l %rms: %m%n

# 输出DEBUG级别以上的日志到D://logs/debug.log
log4j.appender.log = org.apache.log4j.DailyRollingFileAppender
log4j.appender.log.DatePattern = '.'yyyy-MM-dd
log4j.appender.log.File = D://debug.log
log4j.appender.log.Encoding = UTF-8
#log4j.appender.log.Threshold = INFO
log4j.appender.log.layout = org.apache.log4j.PatternLayout
log4j.appender.log.layout.ConversionPattern = %d [%-5p] (%c.%t): %m%n

三、初始化log4j环境

web环境中，启动容器时候，就初始化log4j，在web.xml中配置如下：

<!-- 配置log4j配置文件路径 -->
    <context-param>
        <param-name>log4jConfigLocation</param-name>
        <param-value>classpath:conf/log4j.properties</param-value>
    </context-param>
    <!-- 60s 检测日志配置 文件变化 -->
    <context-param>
        <param-name>log4jRefreshInterval</param-name>
        <param-value>60000</param-value>
    </context-param>

    <!-- 配置Log4j监听器 -->
    <listener>
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
    </listener>

四、使用

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Main {
    private static final Logger logger = LoggerFactory.getLogger(Main.class);
    public static void main(String[] args) {
        int status = 0;
        if (status == 0) {
            logger.info("status:{}", status);
        } else {
            logger.info("status:{}", status);
        }
        logger.info("end!");
    }
}

五、总结

如果需要更换项目的SLF4J日志框架实现，比如logback，不需要修改代码，直接更换日志框架的实现，很方便。

转载：https://www.cnblogs.com/Jason-Xiang/p/6549608.html