log4j的使用

pom

        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>

配置

### 设置###
log4j.rootLogger = debug,stdout,D,E

### 输出信息到控制抬 ###
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 = [%-5p] %d method:%l%n%m%n

### 输出DEBUG 级别以上的日志到=D://logs/demo_jdbc/debug.log ###
log4j.appender.D = org.apache.log4j.DailyRollingFileAppender
log4j.appender.D.File = D://logs/demo_jdbc/debug.log
log4j.appender.D.Append = true
log4j.appender.D.Threshold = DEBUG 
log4j.appender.D.layout = org.apache.log4j.PatternLayout
log4j.appender.D.layout.ConversionPattern = %d  [ %t:%r ] - [ %p ]  %m%n

### 输出ERROR 级别以上的日志到=D://logs/demo_jdbc/error.log ###
log4j.appender.E = org.apache.log4j.DailyRollingFileAppender
log4j.appender.E.File =D://logs/demo_jdbc/error.log 
log4j.appender.E.Append = true
log4j.appender.E.Threshold = ERROR 
log4j.appender.E.layout = org.apache.log4j.PatternLayout
log4j.appender.E.layout.ConversionPattern = %d  [ %t:%r ] - [ %p ]  %m%n

使用

private static Logger logger = Logger.getLogger(UserDaoImpl.class);

    //添加用户
    public boolean insertUser(User user){



        String sql = "insert into user(name,psd) value(?,?)";
        boolean ok= true;
        try {
            PreparedStatement ptmt = conn.prepareStatement(sql);

            ptmt.setString(1,user.getName());
            ptmt.setString(2,user.getPsd());

            if(ptmt.executeUpdate()==0){
                ok = false;
                logger.debug("用户插入失败");
            }else {
                logger.debug("用户插入成功");
            }
        }catch (Exception e){
            e.printStackTrace();
            logger.error("用户插入异常");
        }
        return ok;
    }

效果