Log4j按级别输出日志到不同的文件

原创

tianya23 2011-06-14 16:11:06 博主文章分类：Java基础 ©著作权

文章标签 职场 log4j 休闲 文章分类 Java 后端开发

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spring中对log的使用：

private static final Log logger = LogFactory.getLog(ContextLoader.class);

private static final String DEFAULT_STRATEGIES_PATH = "ContextLoader.properties";

private static final Properties defaultStrategies;

可见：static final中的大写只针对String类型，代表字符串常量，其他类型则一般不用大写。

写法1：方便继承：protected ，不用写类名：this.getClass().getName()

protected Logger logger = LoggerFactory.getLogger(this.getClass().getName());

方法2：在构造函数中初始化

protected static Logger logger; 
    CaseToSourcePanamaMojo(){ 
        logger = LoggerFactory.getLogger(getClass().getName()); 
    }

例子：无配置文件

Logger logger = Logger.getLogger(Log4jSample.class); 
        BasicConfigurator.configure(); 
        logger.setLevel(Level.INFO); 
         
        logger.debug("debug msg."); 
        logger.info("info msg."); 
        logger.warn("warn msg."); 
        logger.error("error msg."); 
        logger.fatal("fatal msg.");

Log4j按级别输出日志到不同的文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">

<log4j:configuration xmlns:log4j='http://jakarta.apache.org/log4j/'>



<appender name="LOG.DEBUG" class="org.apache.log4j.RollingFileAppender">
<param name="File" value="debug.log" />
<param name="MaxFileSize" value="5120KB" />
<param name="MaxBackupIndex" value="10" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{yyy-MM-dd HH:mm:ss} [%-5p] %c {%F:%L} - %m%n" />
</layout>
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMin" value="DEBUG" />
<param name="LevelMax" value="DEBUG" />
</filter>
</appender>

<appender name="LOG.INFO" class="org.apache.log4j.RollingFileAppender">
<param name="File" value="info.log" />
<param name="MaxFileSize" value="5120KB" />
<param name="MaxBackupIndex" value="10" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{yyy-MM-dd HH:mm:ss} [%-5p] %c {%F:%L} - %m%n" />
</layout>
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMin" value="INFO" />
<param name="LevelMax" value="INFO" />
</filter>
</appender>

<appender name="LOG.WARN" class="org.apache.log4j.RollingFileAppender">
<param name="File" value="warn.log" />
<param name="MaxFileSize" value="5120KB" />
<param name="MaxBackupIndex" value="10" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{yyy-MM-dd HH:mm:ss} [%-5p] %c {%F:%L} - %m%n" />
</layout>
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMin" value="WARN" />
<param name="LevelMax" value="WARN" />
</filter>
</appender>

<appender name="LOG.ERROR" class="org.apache.log4j.RollingFileAppender">
<param name="File" value="error.log" />
<param name="MaxFileSize" value="5120KB" />
<param name="MaxBackupIndex" value="10" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{yyy-MM-dd HH:mm:ss} [%-5p] %c {%F:%L} - %m%n" />
</layout>
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMin" value="ERROR" />
<param name="LevelMax" value="ERROR" />
</filter>
</appender>

<appender name="LOG.FATAL" class="org.apache.log4j.RollingFileAppender">
<param name="File" value="fatal.log" />
<param name="MaxFileSize" value="5120KB" />
<param name="MaxBackupIndex" value="10" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{yyy-MM-dd HH:mm:ss} [%-5p] %c {%F:%L} - %m%n" />
</layout>
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMin" value="FATAL" />
<param name="LevelMax" value="FATAL" />
</filter>
</appender>



<root>
<priority value="DEBUG"/>

<appender-ref ref="LOG.DEBUG" />
<appender-ref ref="LOG.INFO" />
<appender-ref ref="LOG.WARN" />
<appender-ref ref="LOG.ERROR" />
<appender-ref ref="LOG.FATAL" />
</root>
</log4j:configuration>

import junit.framework.Test;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.apache.log4j.xml.DOMConfigurator;
public class Simpandfile
{
static Logger logger = Logger.getLogger(Test.class);

public static void main(String args[])
{
// 以property方式读到配置文件。
//PropertyConfigurator.configure("simple.properties");
DOMConfigurator.configure("xmllog4jconfig.xml");
logger.debug("Here is some DEBUG");
logger.info("Here is some INFO");
logger.warn("Here is some WARN");
logger.error("Here is some ERROR");
logger.fatal("Here is some FATAL");
}
}

=============================================================================

1、输出类的相对路径，而不是全部长度

2、ibatis输出sql

log4j.rootLogger=debug,stdout 
log4j.appender.stdout=org.apache.log4j.ConsoleAppender 
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout 
log4j.appender.stdout.layout.conversionPattern=[%5p] %d{mm:ss}/(%F:%M:%L)%n%m%n%n 
log4j.logger.com.ibatis=debug 
log4j.logger.com.ibatis.common.jdbc.SimpleDataSource=debug 
log4j.logger.com.ibatis.common.jdbc.ScriptRunner=debug 
log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate=debug 
log4j.logger.java.sql.Connection=debug 
log4j.logger.java.sql.Statement=debug 
log4j.logger.java.sql.PreparedStatement=debug,stdout