添加slf4j-api和slf4j-log4j12 两个jar包:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.21</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.21</version>
</dependency>
在src/main/resources目录下添加配置文件log4j.properties:
# Root logger option
log4j.rootLogger=INFO, stdout, file
# Redirect log messages to console
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{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Redirect log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
#log4j.appender.file.File=${catalina.home}/logs/myapp.log
log4j.appender.file.File=myapp.log
log4j.appender.file.MaxFileSize=5MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
在需要输出日志的位置使用:
...
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
...
private Logger logger=LoggerFactory.getLogger(UserController.class);
...
logger.info("registrate new user,username="+userForm.getUsername()+",password="+userForm.getPassword());
...