log4j Test

package test;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class Log4jTest {
    private static Log logger = LogFactory.getLog(Log4jTest.class); 
    public static void main(String[] args) {
        logger.error("ERROR");
        logger.debug("DEBUG");
        logger.warn("WARN");
        logger.info("INFO");
        logger.trace("TRACE");
        System.out.println(logger.getClass());
    }

}

1 将commons-logging-1.0.4.jar，log4j.jar放入新建文件夹lib下，然后选中二者，build path 后，classpath发生了改变

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="src" path="src"/>
    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
    <classpathentry kind="lib" path="lib/commons-logging-1.0.4.jar"/>
    <classpathentry kind="lib" path="lib/log4j.jar"/>
    <classpathentry kind="output" path="bin"/>
</classpath>

2 添加 \bin\log4j.properties

# log4j configuration used during build and unit tests

log4j.rootLogger=info,stdout,R
log4j.threshhold=ALL
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ISO8601} %-5p %c{2} (%F:%M(%L)) - %m%n

log4j.appender.R=org.apache.log4j.RollingFileAppender
log4j.appender.R.File=test.txt
log4j.appender.R.MaxFileSize=100KB
log4j.appender.R.MaxBackupIndex=0
log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%d{ISO8601} %-5p %c{2} (%F:%M(%L)) - %m%n

运行，日志文件位置：log4jtest\test.txt