在配置完Hibernate，运行时出现错误：

log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.

解决办法如下:

在src下面新建file名为log4j.properties内容如下:

### direct log messages to stdout ###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p%c{1}:%L - %m%n
### root logger option ###
log4j.rootLogger=warn, stdout
### Hibernate logging options ###
log4j.logger.net.sf.hibernate=info
### log JDBC bind parameters ###
log4j.logger.net.sf.hibernate.type=info
### log PreparedStatement cache activity ###
log4j.logger.net.sf.hibernate.ps.PreparedStatementCache=info

log4j:WARN No appenders could be found for logger