此文主要讲述在初学 Java 时，常用的 Log4J 日志记录配置文件详解及实例源代码整理。希望能对初学 Java 编程的亲们有所帮助。若有不足之处，敬请大神指正，不胜感激！源代码测试通过日期为：2015-1-30 13:54:02，请知悉。
所需的 jar 包下载链接为：http://yunpan.cn/cKE56sxqtQCfP 访问密码 63d8
有关 Log4J 日志文件中日志级别及文件配置的详细情况，在 Log4J 的配置文件（xml、properties）中有详细的介绍，敬请参阅！
- xml 配置文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<!-- ========================== 日志输出等级 ================================ -->
<!-- OFF：最高等级, 用于关闭所有日志记录 -->
<!-- FATAL：输出严重级别的消息 -->
<!-- ERROR：输出错误级别的消息 -->
<!-- WARN：输出警告级别的消息 -->
<!-- INFO：输出信息级别的消息 -->
<!-- DEBUG：输出调试级别的消息 -->
<!-- TRACE：输出跟踪级别的消息 -->
<!-- ALL：最低等级, 用于打开所有日志记录 -->
<!-- 只有当输出日期的级别大于或等于为日志配置器配置的日志级别时, 这个方法才会执行. 指定日志器的日志级别, 不同的日志器会实现不同的日志输出方案 --> <!-- ========================== 自定义输出格式说明 ================================ -->
<!-- %p 输出优先级，即DEBUG，INFO，WARN，ERROR，FATAL -->
<!-- %r 输出自应用启动到输出该log信息耗费的毫秒数 -->
<!-- %c 输出所属的类目，通常就是所在类的全名 -->
<!-- %t 输出产生该日志事件的线程名 -->
<!-- %n 输出一个回车换行符，Windows平台为“\r\n”，Unix平台为“\n” -->
<!-- %d 输出日志时间点的日期或时间，默认格式为ISO8601，也可以在其后指定格式，比如：%d{yyy MMM dd HH:mm:ss,SSS}，输出类似：2002年10月18日 22：10：28，921 -->
<!-- %l 输出日志事件的发生位置，包括类目名、发生的线程，以及在代码中的行数。举例：Testlog4.main(TestLog4.java:10) -->
<!-- ========================================================================== --> <!-- ========================== 输出方式说明================================ -->
<!-- Log4j提供的appender有以下几种: -->
<!-- org.apache.log4j.ConsoleAppender(控制台), -->
<!-- org.apache.log4j.FileAppender(文件), -->
<!-- org.apache.log4j.DailyRollingFileAppender(每天产生一个日志文件), -->
<!-- org.apache.log4j.RollingFileAppender(文件大小到达指定尺寸的时候产生一个新的文件), -->
<!-- org.apache.log4j.WriterAppender(将日志信息以流格式发送到任意指定的地方) -->
<!-- ========================================================================== --> <log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
<!-- 系统运行日志 {TRACE, ERROR} -->
<appender name="InfoConsole" class="org.apache.log4j.ConsoleAppender">
<!-- 不进行缓存, 直接输出 -->
<param name="ImmediateFlush" value="true"></param>
<!-- 指定输出控制台, 默认情况下是 System.out -->
<param name="Target" value="System.err"></param>
<!-- 设置输出文件项目和格式 -->
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="{InfoConsole} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n" />
</layout> <!--限制输出级别 -->
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="ERROR" ></param>
<param name="LevelMin" value="TRACE" ></param>
</filter>
</appender> <!-- 系统运行的错误日志 {ERROR, FATAL}, 单一 -->
<appender name="SysRunningErrorLog" class="org.apache.log4j.FileAppender">
<!-- 设置File参数：日志输出文件名 -->
<param name="File" value="logs/SysRunningErrorLog.log" ></param>
<!-- 设置在重新启动服务时，在原有日志的基础添加新日志 -->
<param name="Append" value="true" ></param> <layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="{SysRunningErrorLog} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n" ></param>
</layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="FATAL" ></param>
<param name="LevelMin" value="ERROR" ></param>
</filter>
</appender> <!-- 系统运行的调试日志 {DEBUG}, 大小-->
<appender name="SysRunningDebugLog" class="org.apache.log4j.RollingFileAppender">
<param name="File" value="logs/SysRunningDebugLog.log" ></param>
<param name="Append" value="true" ></param>
<!-- 设置文件大小 -->
<param name="MaxFileSize" value="5MB" ></param>
<!-- 设置文件备份 -->
<param name="MaxBackupIndex" value="21" ></param>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="{SysRunningDebugLog} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n" ></param>
</layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="DEBUG" ></param>
<param name="LevelMin" value="DEBUG" ></param>
</filter>
</appender> <!-- 系统运行的用户日志 {INFO, WARN}, 每天, LOG -->
<appender name="SysRunCustUseLog" class="org.apache.log4j.DailyRollingFileAppender">
<param name="File" value="logs/SysRunCustUseLog.log" ></param>
<param name="Append" value="true" ></param>
<param name="ImmediateFlush" value="true" ></param>
<param name="DatePattern" value="'-'yyyyMMdd'.log'" ></param>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="{SysRunCustUseLog} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n" ></param>
</layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="WARN" ></param>
<param name="LevelMin" value="INFO" ></param>
</filter>
</appender> <!-- 系统运行的用户日志 {INFO, WARN}, 每天, HTM -->
<appender name="SysRunCustUseLogHtm" class="org.apache.log4j.DailyRollingFileAppender">
<param name="File" value="logs/SysRunCustUseLogHtm.html" ></param>
<param name="Append" value="true" ></param>
<param name="ImmediateFlush" value="true" ></param>
<param name="DatePattern" value="'-'yyyyMMdd'.html'" ></param>
<layout class="org.apache.log4j.HTMLLayout">
<param name="Title" value="Logs info for the current running system from Log4J Message"></param>
</layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="WARN" ></param>
<param name="LevelMin" value="INFO" ></param>
</filter>
</appender> <!-- 系统运行的用户日志 {INFO, WARN} 每天, XML -->
<appender name="SysRunCustUseLogXml" class="org.apache.log4j.DailyRollingFileAppender">
<param name="File" value="logs/SysRunCustUseLogXml.xml"></param>
<param name="DatePattern" value="'-'yyyyMMdd'.xml'"></param>
<layout class="org.apache.log4j.xml.XMLLayout"></layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="WARN"></param>
<param name="LevelMin" value="INFO"></param>
</filter>
</appender> <!-- 系统运行的所有日志 {TRACE, FATAL} -->
<!-- MySQL, sqlserver JDBC 连接实例
<param name="URL" value="jdbc:mysql://127.0.0.1:3306/test" ></param>
<param name="driver" value="com.mysql.jdbc.Driver" ></param>
<param name="URL" value="jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=Aaron" ></param>
<param name="driver" value="com.microsoft.jdbc.sqlserver.SQLServerDriver" ></param>
-->
<!--
<appender name="SysRunInfoDB" class="org.apache.log4j.jdbc.JDBCAppender">
<param name="URL" value="jdbc:oracle:thin:@127.0.0.1:1521:aaron" ></param>
<param name="driver" value="oracle.jdbc.driver.OracleDriver" ></param>
<param name="user" value="hr" ></param>
<param name="password" value="hr" ></param>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="INSERT INTO sysRunInfoLog4J (appenderName, logTime, infoLevel, fileName, threadName, className, lineNumber, infoMsg) VALUES ('SysRunInfoDB', '%d', '%p', '%F', '%t', '%c', '%L', '%m')"></param>
</layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="FATAL"></param>
<param name="LevelMin" value="TRACE"></param>
</filter>
</appender>
--> <!-- 发邮件（只有ERROR时才会发送！） -->
<!-- <appender name="adMail" class="org.apache.log4j.net.SMTPAppender">
<param name="threshold" value="debug"></param>
<param name="BufferSize" value="512"></param>
<param name="From" value="test@163.com"></param>
<param name="SMTPHost" value="smtp.163.com"></param>
<param name="Subject" value="Logs info for the current running system from Log4J Message"></param>
<param name="To" value="test@163.com"></param>
<param name="SMTPUsername" value="test"></param>
<param name="SMTPPassword" value="test"></param>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="{adMail} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n"></param>
</layout> <filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="FATAL"></param>
<param name="LevelMin" value="ERROR"></param>
</filter>
</appender> --> <!--- 异步测试，当日志达到缓存区大小时候执行所包的appender -->
<appender name="ASYNC" class="org.apache.log4j.AsyncAppender">
<param name="BufferSize" value="256"></param>
<appender-ref ref="SysRunningDebugLog"></appender-ref>
<appender-ref ref="SysRunCustUseLog"></appender-ref>
<appender-ref ref="SysRunCustUseLogHtm"></appender-ref>
<appender-ref ref="SysRunCustUseLogXml"></appender-ref>
</appender> <!--通过<logger>的定义可以将各个包中的类日志输出到不同的日志文件中 -->
<!--<logger name="test.log4j" additivity="false">
<level value="INFO"></level>
<appender-ref ref="InfoConsole"></appender-ref>
<appender-ref ref="adDatabase"></appender-ref>
<appender-ref ref="SysRunningErrorLog"></appender-ref>
</logger>--> <!--通过<category></category>的定义可以将各个包中的类日志输出到不同的日志文件中 -->
<!--<category name="test.log4j.JavaLog4J.test" additivity="false">
<level value="DEBUG"></level>
<appender-ref ref="adDailyLogFile"></appender-ref>
</category>--> <!-- 控制输出appender项 -->
<root>
<!-- 控制日志输出的最低级别, 则appender输出日志的最低级别为priority|LevelMin|logger|category中的高级别 -->
<priority value="ALL"></priority>
<!-- 系统运行日志 {TRACE, ERROR} -->
<appender-ref ref="InfoConsole"></appender-ref>
<!-- 系统运行的错误日志 {ERROR, FATAL}, 单一 -->
<appender-ref ref="SysRunningErrorLog"></appender-ref>
<!-- 系统运行的调试日志 {DEBUG}, 大小-->
<appender-ref ref="SysRunningDebugLog"></appender-ref>
<!-- 系统运行的用户日志 {INFO, WARN}, 每天, LOG -->
<appender-ref ref="SysRunCustUseLog"></appender-ref>
<!-- 系统运行的用户日志 {INFO, WARN}, 每天, HTM -->
<appender-ref ref="SysRunCustUseLogHtm"></appender-ref>
<!-- 系统运行的用户日志 {INFO, WARN} 每天, XML -->
<appender-ref ref="SysRunCustUseLogXml"></appender-ref>
<!-- 系统运行的所有日志 {TRACE, FATAL}, 运行此配置, 需要配置相应的数据库信息 -->
<!-- <appender-ref ref="SysRunInfoDB"></appender-ref> -->
</root>
</log4j:configuration>
Log4J XML 文件配置文件详情，内含日志级别及文件输出等详解
- properties 配置文件
# adDatabase \u53D1\u9001\u6570\u636E\u5E93\u4FE1\u606F\u914D\u7F6E
log4j.rootLogger=INFO,adInfoConsole,adInfoFile,adDailyLogFile,adRollingFile,adInfoHtml,adCust
log4j.addivity.org.apache=true # Send to console
log4j.appender.adInfoConsole=org.apache.log4j.ConsoleAppender
# output level
log4j.appender.adInfoConsole.Threshold=INFO
log4j.appender.adInfoConsole.Target=System.err
log4j.appender.adInfoConsole.layout=org.apache.log4j.PatternLayout
log4j.appender.adInfoConsole.layout.ConversionPattern={adInfoConsole} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n
log4j.appender.adInfoConsole.ImmediateFlush=true # Send to file
log4j.appender.adInfoFile=org.apache.log4j.FileAppender
log4j.appender.adInfoFile.Threshold = INFO
log4j.appender.adInfoFile.File=logs/adInfoFile.log
log4j.appender.adInfoFile.Append=true
log4j.appender.adInfoFile.layout=org.apache.log4j.PatternLayout
log4j.appender.adInfoFile.layout.ConversionPattern={adInfoFile} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n # Send to daily file
log4j.appender.adDailyLogFile = org.apache.log4j.DailyRollingFileAppender
log4j.appender.adDailyLogFile.Threshold = ERROR
# file path
log4j.appender.adDailyLogFile.File = logs/adErrorLogFile.log
# default true: add the info to the log file tail; false: rewrite the log file
log4j.appender.adDailyLogFile.Append = true
# directly output the info
log4j.appender.adDailyLogFile.ImmediateFlush = true
# format the file name
log4j.appender.adDailyLogFile.DatePattern = '-'yyyyMMdd'.log'
# '-'yyyy-MM: every month
# '-'yyyy-ww: every week
# '-'yyyy-MM-dd: every day
# '-'yyyy-MM-dd-a: every middle day and night
# '-'yyyy-MM-dd-HH: every hour
# '-'yyyy-MM-dd-HH-mm: every minute
# content format
log4j.appender.adDailyLogFile.layout = org.apache.log4j.PatternLayout
log4j.appender.adDailyLogFile.layout.ConversionPattern ={adDailyLogFile} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n # Send to file
log4j.appender.adRollingFile=org.apache.log4j.RollingFileAppender
log4j.appender.adRollingFile.Threshold=ERROR
log4j.appender.adRollingFile.File=logs/adRollingFile.log
log4j.appender.adRollingFile.Append=true
# the file size (KB, MB, GB)
log4j.appender.adRollingFile.MaxFileSize=1MB
# max backup count
log4j.appender.adRollingFile.MaxBackupIndex=3
log4j.appender.adRollingFile.layout=org.apache.log4j.PatternLayout
log4j.appender.adRollingFile.layout.ConversionPattern={adErrorRollingFile} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n # Send to html
log4j.appender.adInfoHtml = org.apache.log4j.RollingFileAppender
log4j.appender.adInfoHtml.Threshold = INFO
log4j.appender.adInfoHtml.File = logs/adInfoHtml.html
log4j.appender.adInfoHtml.Append = true
log4j.appender.adInfoHtml.MaxFileSize = 3MB
log4j.appender.adInfoHtml.MaxBackupIndex = 3
log4j.appender.adInfoHtml.layout = org.apache.log4j.HTMLLayout
# the html file name
log4j.appender.adInfoHtml.layout.Title =Logs info for the current running system from Log4J Message # Send to database
# log4j.appender.adDatabase=org.apache.log4j.jdbc.JDBCAppender
# log4j.appender.adDatabase.Threshold=DEBUG
# log4j.appender.adDatabase.URL=jdbc:mysql://localhost:3306/test
# log4j.appender.adDatabase.driver=com.mysql.jdbc.Driver
# log4j.appender.adDatabase.URL=jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=Aaron
# log4j.appender.adDatabase.driver=com.microsoft.jdbc.sqlserver.SQLServerDriver
# log4j.appender.adDatabase.URL=jdbc:oracle:thin:@127.0.0.1:1521:aaron
# log4j.appender.adDatabase.driver=oracle.jdbc.driver.OracleDriver
# log4j.appender.adDatabase.user=hr
# log4j.appender.adDatabase.password=hr
# log4j.appender.adDatabase.sql=INSERT INTO sysRunInfoLog4J (appenderName, logTime, infoLevel, fileName, threadName, className, lineNumber, infoMsg) VALUES ('adDatabase', '%d', '%p', '%F', '%t', '%c', '%L', '%m')
# log4j.appender.adDatabase.layout=org.apache.log4j.PatternLayout
# log4j.appender.adDatabase.layout.ConversionPattern=adDatabase %d %p %F %t %c %L %m # Custom
log4j.appender.adCust=org.apache.log4j.DailyRollingFileAppender
log4j.appender.adCust.File=logs/SampleMsgLog4J.xml
log4j.appender.adCust.DatePattern='-'yyyyMMdd-HH'.xml'
log4j.appender.adCust.layout=org.apache.log4j.xml.XMLLayout # Send to mail
log4j.appender.adMail=org.apache.log4j.net.SMTPAppender
log4j.appender.adMail.Threshold=FATAL
log4j.appender.adMail.BufferSize=10
log4j.appender.adMail.From=web@www.wuset.com
log4j.appender.adMail.SMTPHost=www.wusetu.com
log4j.appender.adMail.Subject=Logs info for the current running system from Log4J Message
log4j.appender.adMail.To=web@www.wusetu.com
log4j.appender.adMail.layout=org.apache.log4j.PatternLayout
log4j.appender.adMail.layout.ConversionPattern={adFatalMail} - %d - %-5p - [%F] [%t] [%c:%L] - %m%n
Log4J properties 文件配置详情实例
- Java Log4J 源代码简单实例
/**
* Aaron.ffp Inc.
* Copyright (c) 2004-2015 All Rights Reserved.
*/
package main.java.aaron.java.demo; import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
//import org.apache.log4j.xml.DOMConfigurator; /**
* Log4J 演示实例
* @author Aaron.ffp
* @version V1.0.0: autoUISelenium main.java.aaron.java.demo Log4JDemo.java, 2015-1-30 13:54:02 Exp $
*/
public class Log4JDemo {
private static Logger logger = Logger.getLogger(Log4JDemo.class.getName()); /**
* 方法主入口
* @author Aaron.ffp
* @version V1.0.0: autoUISelenium main.java.aaron.java.demo Log4JDemo.java main, 2015-1-30 13:54:02 Exp $
*
* @param args
*/
public static void main(String[] args) {
// 初始化log4j的配置文件
// DOMConfigurator.configure("src/log4j.xml");
PropertyConfigurator.configure("src/log4j.properties"); // 记录debug级别的信息
logger.trace("This is trace message."); // 记录debug级别的信息
logger.debug("This is debug message."); // 记录info级别的信息
logger.info("This is info message."); // 记录warn级别的信息
logger.warn("This is warn message."); // 记录error级别的信息
logger.error("This is error message."); // 记录fatal级别的信息
logger.fatal("This is fatal message.");
}
}
Java Log4J 源代码简单实例
至此， Java学习-007-Log4J 日志记录配置文件详解及实例源代码 顺利完结，希望此文能够给初学 Java 的您一份参考。
最后，非常感谢亲的驻足，希望此文能对亲有所帮助。热烈欢迎亲一起探讨，共同进步。非常感谢！ ^_^