log4j升级到log4j2

log4j升级到log4j2

1、导入依赖

log4j2应尽量使用同一版本，否则可能出现不兼容的情况

<dependency>
    <groupId>org.apache.logging.log4jgroupId>
    <artifactId>log4j-1.2-apiartifactId>
    <version>2.9.1version>
dependency>
<dependency>
    <groupId>org.apache.logging.log4jgroupId>
    <artifactId>log4j-webartifactId>
    <version>2.9.1version>
dependency>

<dependency>
    <groupId>org.apache.logging.log4jgroupId>
    <artifactId>log4j-coreartifactId>
    <version>2.9.1version>
dependency>

<dependency>
    <groupId>org.apache.logging.log4jgroupId>
    <artifactId>log4j-apiartifactId>
    <version>2.9.1version>
dependency>

2、log4j.properties升级为log4j2.properties

log4j2支持log4j2.properties配置文件

status = warn
name = MyApp
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#指定输出源‘类型’为控制台
appender.console.type = Console
appender.console.name = consoleLogDemo
appender.console.filter.threshold.type = ThresholdFilter
appender.console.filter.threshold.level = debug
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = [%-5p] [%d{yyyy-MM-dd HH:mm:ss}] [%C{1}:%M:%L] %m%n
appender.console.target = System_out
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appender.rolling.type = RollingFile
appender.rolling.name = fileLogDemo
appender.rolling.filter.threshold.type = ThresholdFilter
appender.rolling.filter.threshold.level = info
appender.rolling.layout.type = PatternLayout
appender.rolling.layout.pattern = [%-5p] [%d{yyyy-MM-dd HH:mm:ss}] [%C{1}:%M:%L] %m%n
appender.rolling.append = true
appender.rolling.fileName =/data/logs/workflow/web.log
appender.rolling.filePattern=/data/logs/wokflow/web.log.%d{yyyy-MM-dd}
appender.rolling.policies.type = Policies
appender.rolling.policies.time.type = TimeBasedTriggeringPolicy
appender.rolling.policies.time.interval = 2
appender.rolling.policies.time.modulate = true
appender.rolling.policies.size.type = SizeBasedTriggeringPolicy
appender.rolling.policies.size.size=100MB
appender.rolling.strategy.type = DefaultRolloverStrategy
appender.rolling.strategy.max = 5
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logger.rolling.name = com.iqiyi
logger.rolling.level = info
logger.rolling.additivity = false
logger.rolling.appenderRef.rolling.ref = fileLogDemo
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#指明根级日志的级别
rootLogger.level = info
#指定哪些appender输出源是根级日志的输出级别
rootLogger.appenderRef.consolelogdemo.ref = consoleLogDemo
rootLogger.appenderRef.filelogdemo.ref = fileLogDemo

参考文档：

3、log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration status="error" monitorInterval="30">
    <Properties>
        <Property name="baseDir">logProperty>
    Properties>
    
    <appenders>
        
        <Console name="Console" target="SYSTEM_OUT">
            
            <ThresholdFilter level="trace" onMatch="ACCEPT" onMismatch="DENY"/>
            <PatternLayout pattern="%d %5p %c:%L - %m %throwable{}%n"/>
        Console>
        
        <Async name="ASYNC" bufferSize="262144" includeLocation="true">
            <AppenderRef ref="RollingFile"/>
        Async>
        
        <RollingFile name="RollingFile" fileName="${baseDir}/info.log" filePattern="${baseDir}/info.log.%d{yyyy-MM-dd}">
            
            <PatternLayout pattern="%d %5p %c:%L - %m %throwable{separator( --> )}%n"/>
            
            <TimeBasedTriggeringPolicy interval="1"/>
            <DefaultRolloverStrategy>
                
                <Delete basePath="${baseDir}">
                    <IfFileName glob="info.log.*"/>
                    <IfLastModified age="7d"/>
                Delete>
            DefaultRolloverStrategy>
        RollingFile>
    appenders>
    
    <loggers>
        <root level="INFO">
            <appender-ref ref="Console"/>
            <appender-ref ref="RollingFile"/>
        root>
        
        <logger name="org.hibernate.validator" level="ERROR"/>
    loggers>
configuration>

4、修改web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
         version="2.5">
     
    <listener>
        <listener-class>org.apache.logging.log4j.web.Log4jServletContextListenerlistener-class>
    listener>
    <filter>
        <filter-name>log4jServletFilterfilter-name>
        <filter-class>org.apache.logging.log4j.web.Log4jServletFilterfilter-class>
    filter>
    <filter-mapping>
        <filter-name>log4jServletFilterfilter-name>
        <url-pattern>/*url-pattern>
        <dispatcher>REQUESTdispatcher>
        <dispatcher>FORWARDdispatcher>
        <dispatcher>INCLUDEdispatcher>
        <dispatcher>ERRORdispatcher>
    filter-mapping>
    <context-param>
        <param-name>log4jContextNameparam-name>
        <param-value>myApplicationparam-value>
    context-param>
    <context-param>
        <param-name>log4jConfigurationparam-name>
        <param-value>classpath:log4j2.propertiesparam-value>
    context-param>
    

在web.xml中移除旧的log4j.property的配置

 <context-param>
      <param-name>log4jConfigLocationparam-name>
      <param-value>classpath:log4j.propertiesparam-value>
 context-param>

5、log4j2测试

使用的LogManager.getLogger(Object.class)方式获取对象

加入测试类，并运行。如在项目磁盘目录下正常输出日志内容则说明log4j2添加成功：

public class TestLogger {
    private static final Logger log = LoggerFactory.getLogger(TestLogger.class);
    public static void main(String[] args) {
        int number=10;
        log.info("AAAAAAAAAAInfo : number is " + number);
        log.warn("AAAAAAAAAAAAAAAWarning : number is " + number);
        log.debug("AAAAAAAAADebug : number is " + number);
        log.error("AAAAAAAAAAAError : number is " + number);
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    }
}