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  • MyBastis初次环境配置讲解

    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)

    1.导包

    当然还要有数据库驱动包

    2.写xml配置

    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]

    
    
    

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  • 原文地址:https://www.cnblogs.com/xiaohui123-com/p/6434123.html
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