MyBatis笔记——初次环境配置

ゝ一纸荒年。 2021-12-20 05:29 278阅读 0赞

## 简单介绍 ##

MyBatis 本是apache的一个开源项目iBatis, 2010年这个项目由apache software foundation 迁移到了google code，并且改名为MyBatis 。2013年11月迁移到Github。  
iBATIS一词来源于“internet”和“abatis”的组合，是一个基于Java的持久层框架。iBATIS提供的持久层框架包括SQL Maps和Data Access Objects（DAO）

![流程][20150920192527510]  
![功能][20150920192551793]

--------------------

## 1.导包 ##

核心包  
![核心包][20150920192911633]

依赖包  
![依赖包][20150920192946354]

**当然还要有数据库驱动包**

--------------------

## 2.写xml配置 ##

项目结构如下  
![项目结构][20150920194008270]

### 2.1添加SqlMapConfig.xml配置文件 ###

<?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>
        <environments default="development">
            <environment id="development">
                <transactionManager type="JDBC" />
                <dataSource type="POOLED">
                    <property name="driver" value="com.mysql.jdbc.Driver" />
                    <property name="url" value="jdbc:mysql://localhost:3306/db_pwc" />
                    <property name="username" value="pwc" />
                    <property name="password" value="123456" />
                </dataSource>
            </environment>
        </environments>
        <mappers>
            <mapper resource="com/pwc/pojo/User.xml" />
        </mappers>
    </configuration>

### 2.2添加POJO类User.java ###

package com.pwc.pojo;
    public class User {
          
        private int id;
        private String name;
        private int age;
        public int getId() {
            return id;
        }
        public void setId(int id) {
            this.id = id;
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public int getAge() {
            return age;
        }
        public void setAge(int age) {
            this.age = age;
        }
        @Override
        public String toString() {
            return "User [id=" + id + ", name=" + name + ", age=" + age + "]";
        }
        public User(int id, String name, int age) {
            super();
            this.id = id;
            this.name = name;
            this.age = age;
        }
        public User() {
        }
    }

### 2.3添加POJO类User的映射文件User.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="com.pwc.dao.mapper.UserMapper">
        <select id="findById" parameterType="int" resultType="com.pwc.pojo.User">
            SELECT * FROM User WHERE id = #{id}
        </select>
    
        <insert id="insert" parameterType="com.pwc.pojo.User">
            INSERT INTO User(name,age) VALUES(#{name},#{age})
        </insert>
    
        <delete id="deleteById" parameterType="int">
            DELETE * FROM User WHERE id=#{id}
    
        </delete>
    
        <select id="findByAge" parameterType="int" resultType="com.pwc.pojo.User">
            SELECT * FROM User WHERE age=#{age}
        </select>
    
    </mapper>

--------------------

## 3.测试 ##

package com.pwc.test;
    
    import org.apache.ibatis.session.SqlSession;
    import org.apache.ibatis.session.SqlSessionFactory;
    import org.apache.ibatis.session.SqlSessionFactoryBuilder;
    
    import com.pwc.pojo.User;
    
    public class Test {
    
        public static void main(String[] args) {
            SqlSessionFactoryBuilder builder=new SqlSessionFactoryBuilder();
            SqlSessionFactory factory = builder.build(Test.class.getClassLoader().getResourceAsStream("SqlMapConfig.xml"));
    
            SqlSession session = factory.openSession();
            User user=session.selectOne("findById", 1);
            System.out.println(user.toString());
    
        }
    
    }

--------------------

**测试结果如下：**  
User \[id=1, name=pwc, age=18\]

转载于:https://www.cnblogs.com/pwc1996/p/4839135.html

[20150920192527510]: /images/20211220/ac3573625cff4fc09acd234be10c5167.png
[20150920192551793]: /images/20211220/25a84d7be5344d4cbb5af9ae416a8ec5.png
[20150920192911633]: /images/20211220/7eb0069d82564da4905b66d4c06a345e.png
[20150920192946354]: /images/20211220/b7ef071a85f8425c8464c613675119af.png
[20150920194008270]: /images/20211220/30d27bd2fb144323a6cba0e1adc24ff6.png