在《开发Spring MVC应用程序(1)》中，由于对log4j的配置有问题，导致log4j无法正常工作。现对log4j做如下修正：
# For JBoss: Avoid to setup log4j outside $JBOSS_HOME/server/default/deploy/log4j.xml! # For all other servers: Comment out the Log4J listener in web.xml too. log4j.rootLogger=INFO, stdout, logfile log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - <%m>%n log4j.appender.logfile=org.apache.log4j.RollingFileAppender log4j.appender.logfile.File=springapp.log log4j.appender.logfile.MaxFileSize=512KB # Keep three backup files. log4j.appender.logfile.MaxBackupIndex=3 # Pattern to output: date priority [category] - message log4j.appender.logfile.layout=org.apache.log4j.PatternLayout log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] - %m%n
去掉第三行的注释，指定log文件名为springapp.log，并在log4j.properties同目录下创建该空文件。log4j.properties内容的具体含义可以参考《 Log4j日志管理系统简单使用说明 》
