这是一个简单的log4j配置文件内容，具体配置信息项的含义，可以查看http://www.cnblogs.com/chenxqNo01/p/6370340.html，里面有具体配置详解
log4j.rootLogger = debug, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %5p (%c.java:%L):%m%n
log4j.appender.msm=org.apache.log4j.RollingFileAppender
log4j.appender.msm.File=log/bbtree-020.log
log4j.appender.msm.layout=org.apache.log4j.PatternLayout
log4j.appender.msm.layout.ConversionPattern=%d %5p (%c.java:%L):%m%n
log4j.logger.java.sql=DEBUG
log4j.logger.java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG
log4j.logger.org.apache=DEBUG
log4j.logger.org.apache.ibatis=DEBUG
log4j.logger.org.apache.ibatis.common.jdbc.SqlMapClientDelegate=DEBUG
log4j.logger.org.apache.ibatis.common.jdbc.ScriptRunner=DEBUG
log4j.logger.org.apache.ibatis.common.jdbc.SimpleDataSource=DEBUG
log4j.logger.org.apache.ibatis.cache.decorators.LoggingCache=DEBUG
log4j.logger.org.springframework.jdbc=DEBUG
log4j.logger.com.bbtree.common=DEBUG