日志

日志工厂

如果一个数据库操作，出现了异常，我们需要排错。日志就是最好的助手！
曾经：sout,debug
现在：日志工厂

SLF4J
LOG4J【掌握】
LOG4J2
JDK_LOGGING
COMMONS_LOGGING
STDOUT_LOGGING 【掌握】
NO_LOGGING

在Mybatis中，具体使用哪一个日志实现，在设置中决定。
STDOUT_LOGGING标准日志输出
在mybatis核心配置文件中，配置我们的日志！

   <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

LOG4J

什么是LOG4j？

Apache Log4j 是一个功能强大、工业级的 Java 日志框架，由 API、其实现和组件组成，以帮助部署各种用例。
我们也可以控制每一条日志的输出格式
通过定义每一条日志信息的级别，我们能够更加细致地控制日志的生成过程
通过一个配置文件来灵活地进行配置，而不需要修改应用的代码

1、先导入LOG4J的包 <pom.xml>

 <dependencies>
        <!-- Source: https://mvnrepository.com/artifact/log4j/log4j -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
            <scope>compile</scope>
        </dependency>
    </dependencies>

2、log4j.properties

#将等级为DEBUG的日志信息输出到console和file这两个目的地，console和file的定义在下面的代码
log4j.rootLogger=DEBUG,console,file

#控制台输出的相关设置
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.Threshold=DEBUG
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=[%c]-%m%n

#文件输出的相关设置
log4j.appender.file = org.apache.log4j.RollingFileAppender
log4j.appender.file.File=./log/kuang.log
log4j.appender.file.MaxFileSize=10mb
log4j.appender.file.Threshold=DEBUG
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=[%p][%d{yy-MM-dd}][%c]%m%n

#日志输出级别
log4j.logger.org.mybatis=DEBUG
log4j.logger.java.sql=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

3、配置log4j为日志的实现<mybatis-config.xml>

 <settings>
        <!-- 标准的日志工厂实现 -->
        <!--<setting name="logImpl" value="STDOUT_LOGGING"/>-->
        <setting name="logImpl" value="LOG4J"/>
    </settings>

4、Log4j的使用，直接测试运行刚才的查询

D:\jdk-25.0.1\bin\java.exe "-javaagent:C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2025.3\captureAgent\debugger-agent.jar=file:///C:/Users/ADMINI~1/AppData/Local/Temp/capture14781722853202405843.props" -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:D:\IDEA\IntelliJ IDEA 2025.3.1.1\lib\idea_rt.jar=59402" -Dkotlinx.coroutines.debug.enable.creation.stack.trace=false -Ddebugger.agent.enable.coroutines=true -Dkotlinx.coroutines.debug.enable.flows.stack.trace=true -Dkotlinx.coroutines.debug.enable.mutable.state.flows.stack.trace=true -Ddebugger.async.stack.trace.for.all.threads=true -Dfile.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -classpath "D:\IDEA\IntelliJ IDEA 2025.3.1.1\lib\idea_rt.jar;D:\IDEA\IntelliJ IDEA 2025.3.1.1\plugins\junit\lib\junit6-rt.jar;D:\IDEA\IntelliJ IDEA 2025.3.1.1\plugins\junit\lib\junit5-rt.jar;D:\IDEA\IntelliJ IDEA 2025.3.1.1\plugins\junit\lib\junit-rt.jar;F:\IDEA project\mybatis\mybatis-study\mybatis-04\target\test-classes;F:\IDEA project\mybatis\mybatis-study\mybatis-04\target\classes;D:\apache-maven-3.9.11\log4j\log4j\1.2.17\log4j-1.2.17.jar;D:\apache-maven-3.9.11\com\mysql\mysql-connector-j\8.0.33\mysql-connector-j-8.0.33.jar;D:\apache-maven-3.9.11\com\google\protobuf\protobuf-java\3.21.9\protobuf-java-3.21.9.jar;D:\apache-maven-3.9.11\org\mybatis\mybatis\3.5.17\mybatis-3.5.17.jar;D:\apache-maven-3.9.11\junit\junit\4.13.2\junit-4.13.2.jar;D:\apache-maven-3.9.11\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar" com.intellij.rt.junit.JUnitStarter -ideVersion5 -junit4 com.god.dao.UserDaoTest,getUserList
[org.apache.ibatis.logging.LogFactory]-Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
[org.apache.ibatis.logging.LogFactory]-Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
[org.apache.ibatis.io.VFS]-Class not found: org.jboss.vfs.VFS
[org.apache.ibatis.io.JBoss6VFS]-JBoss 6 VFS API is not available in this environment.
[org.apache.ibatis.io.VFS]-Class not found: org.jboss.vfs.VirtualFile
[org.apache.ibatis.io.VFS]-VFS implementation org.apache.ibatis.io.JBoss6VFS is not valid in this environment.
[org.apache.ibatis.io.VFS]-Using VFS adapter org.apache.ibatis.io.DefaultVFS
[org.apache.ibatis.io.DefaultVFS]-Find JAR URL: file:/F:/IDEA%20project/mybatis/mybatis-study/mybatis-04/target/classes/com/god/pojo
[org.apache.ibatis.io.DefaultVFS]-Not a JAR: file:/F:/IDEA%20project/mybatis/mybatis-study/mybatis-04/target/classes/com/god/pojo
[org.apache.ibatis.io.DefaultVFS]-Reader entry: User.class
[org.apache.ibatis.io.DefaultVFS]-Listing file:/F:/IDEA%20project/mybatis/mybatis-study/mybatis-04/target/classes/com/god/pojo
[org.apache.ibatis.io.DefaultVFS]-Find JAR URL: file:/F:/IDEA%20project/mybatis/mybatis-study/mybatis-04/target/classes/com/god/pojo/User.class
[org.apache.ibatis.io.DefaultVFS]-Not a JAR: file:/F:/IDEA%20project/mybatis/mybatis-study/mybatis-04/target/classes/com/god/pojo/User.class
[org.apache.ibatis.io.DefaultVFS]-Reader entry: ����   E :
[org.apache.ibatis.io.ResolverUtil]-Checking to see if class com.god.pojo.User matches criteria [is assignable to Object]
[org.apache.ibatis.datasource.pooled.PooledDataSource]-PooledDataSource forcefully closed/removed all connections.
[org.apache.ibatis.datasource.pooled.PooledDataSource]-PooledDataSource forcefully closed/removed all connections.
[org.apache.ibatis.datasource.pooled.PooledDataSource]-PooledDataSource forcefully closed/removed all connections.
[org.apache.ibatis.datasource.pooled.PooledDataSource]-PooledDataSource forcefully closed/removed all connections.
[org.apache.ibatis.transaction.jdbc.JdbcTransaction]-Opening JDBC Connection
[org.apache.ibatis.datasource.pooled.PooledDataSource]-Created connection 1064905627.
[org.apache.ibatis.transaction.jdbc.JdbcTransaction]-Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@3f792b9b]
[com.god.dao.UserMapper.getUserById]-==>  Preparing: select * from mybatis.user where id = ?;
[com.god.dao.UserMapper.getUserById]-==> Parameters: 1(Integer)
[com.god.dao.UserMapper.getUserById]-<==      Total: 1
User{id=1, name='迪迦', password='123'}
[org.apache.ibatis.transaction.jdbc.JdbcTransaction]-Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@3f792b9b]
[org.apache.ibatis.transaction.jdbc.JdbcTransaction]-Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@3f792b9b]
[org.apache.ibatis.datasource.pooled.PooledDataSource]-Returned connection 1064905627 to pool.

Process finished with exit code 0

简单使用

在要使用Log4j的类中，导入包import org.apache.log4j.Logger;
日志对象，参数为当前类的class

static Logger logger = Logger.getLogger(UserDaoTest.class);

日志级别

       logger.info("info:进入了testLog4j");
       logger.debug("debug:进入了testLog4j");
       logger.error("error:进入了testLog4j");

<UserDaoTest.Java>文件

package com.god.dao;

import com.god.dao.UserMapper;
import com.god.pojo.User;
import com.god.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.apache.log4j.Logger;
import org.junit.Test;

public class UserDaoTest {

    static Logger logger = Logger.getLogger(UserDaoTest.class);
    @Test
    public void getUserList() {
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        
        logger.info("测试，进入getUserList方法成功！！！");
        
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        User user = mapper.getUserById(1);
        System.out.println(user);
        sqlSession.close();
    }

    @Test
    public void testLog4j() {
       logger.info("info:进入了testLog4j");
       logger.debug("debug:进入了testLog4j");
       logger.error("error:进入了testLog4j");
    }
}

posted @ 2026-02-14 11:28 Dominus 阅读(1) 评论(0) 收藏举报

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日志

日志工厂

LOG4J

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