Mybaties框架入门

川长思鸟来 2021-11-23 02:46 340阅读 0赞

# Mybaties框架入门 #

## mybatis是一个java持久层框架，java中操作关系型 数据库用的是jdbc，mybatis是对jdbc的一个封装。 ##

## 1.1导的包 ##

![在这里插入图片描述][20190725174752645.png]

## 1.2IDEA目录架构 ##

![在这里插入图片描述][20190725175109133.png]

## 2.1数据源jdbc.properties(因人而异) ##

jdbc.driver=com.mysql.jdbc.Driver
    jdbc.url=jdbc\:mysql\://127.0.0.1\:3306/ts
    jdbc.username=root
    jdbc.password=root

## 2.2数据库t\_user(因人而异) ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MjA1MTI5_size_16_color_FFFFFF_t_70]

## 3.1pojo ##

package com.baidu.pojo;
    
    public class User {
        public Integer getId() {
            return id;
        }
    
        public void setId(Integer id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        private Integer id;
        private  String name;
    }

## 3.2核心配置文件SqlMapConfig.xml ##

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE configuration
            PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
            "http://mybatis.org/dtd/mybatis-3-config.dtd">
    <configuration>
    
        <properties resource="jdbc.properties"></properties>
    
        <environments default="development">
            <environment id="development">
                <transactionManager type="JDBC"/>
                <dataSource type="POOLED">
                    <property name="driver" value="${jdbc.driver}"/>
                    <property name="url" value="${jdbc.url}"/>
                    <property name="username" value="${jdbc.username}"/>
                    <property name="password" value="${jdbc.password}"/>
                </dataSource>
            </environment>
        </environments>
    
    
        <mappers>
            <mapper resource="sqlMap/UserMapper.xml"/>
            
        </mappers>
    </configuration>

## 3.3UserMapper.xml ##

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE mapper
            PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
            "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
    
    <mapper namespace="test">
        <select id="selectUser" resultType="com.baidu.pojo.User" >
          select * from t_user
        </select>
    </mapper>

## 3.4日志文件log4j.properties ##

# Global logging configuration，建议开发环境中要用debug
    log4j.rootLogger=DEBUG, stdout
    # Console output...
    log4j.appender.stdout=org.apache.log4j.ConsoleAppender
    log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
    log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

## 3.5测试类 ##

package com.baidu.test;
    
    import org.apache.ibatis.io.Resources;
    import org.apache.ibatis.session.SqlSession;
    import org.apache.ibatis.session.SqlSessionFactory;
    import org.apache.ibatis.session.SqlSessionFactoryBuilder;
    import java.io.IOException;
    import java.io.InputStream;
    import java.util.List;
    
    public class TesyMybaties {
        public static void main(String[] args) throws IOException {
    
            String resource = "SqlMapConfig.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    
            SqlSession session = sqlSessionFactory.openSession();
            List<Object> list=session.selectList("test.selectUser");
            System.out.println(list.size());
          session.close();
    
        }
    
    }

## 3.6运行结果 ##

"C:\Program Files\Java\jdk1.8.0_73\bin\java.exe" "-javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2018.3.5\lib\idea_rt.jar=62267:D:\Program Files\JetBrains\IntelliJ IDEA 2018.3.5\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_73\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_73\jre\lib\rt.jar;E:\IDEA\MySpring0722\out\production\Mybaties;E:\IDEA\Mybaties\lib\asm-3.3.1.jar;E:\IDEA\Mybaties\lib\cglib-2.2.2.jar;E:\IDEA\Mybaties\lib\log4j-1.2.17.jar;E:\IDEA\Mybaties\lib\mybatis-3.2.7.jar;E:\IDEA\Mybaties\lib\slf4j-api-1.7.5.jar;E:\IDEA\Mybaties\lib\log4j-api-2.0-rc1.jar;E:\IDEA\Mybaties\lib\log4j-core-2.0-rc1.jar;E:\IDEA\Mybaties\lib\javassist-3.17.1-GA.jar;E:\IDEA\Mybaties\lib\slf4j-log4j12-1.7.5.jar;E:\IDEA\Mybaties\lib\commons-logging-1.1.1.jar;E:\IDEA\Mybaties\lib\mysql-connector-java-5.1.7-bin.jar" com.baidu.test.TesyMybaties
    DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.slf4j.Slf4jImpl' adapter.
    DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
    DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
    DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
    DEBUG [main] - PooledDataSource forcefully closed/removed all connections.
    DEBUG [main] - Opening JDBC Connection
    DEBUG [main] - Created connection 1734853116.
    DEBUG [main] - Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@6767c1fc]
    DEBUG [main] - ==>  Preparing: select * from t_user 
    DEBUG [main] - ==> Parameters: 
    DEBUG [main] - <==      Total: 5
    5
    DEBUG [main] - Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@6767c1fc]
    DEBUG [main] - Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@6767c1fc]
    DEBUG [main] - Returned connection 1734853116 to pool.
    
    Process finished with exit code 0

[20190725174752645.png]: /images/20211122/a6421759a31d4cae9666a8e41887c8bd.png
[20190725175109133.png]: /images/20211122/5bc96b0ffc734ccb80804bb9565c29e7.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5MjA1MTI5_size_16_color_FFFFFF_t_70]: /images/20211122/cf9a612be1054b1da0dfdab085418a88.png