springboot-mybatis xml配置

    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 。
    MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。

    

本机主要介绍mybatis通过xml配置方式操作数据库，这也是项目开发中通用的一种，将sql编写在xml中，便于维护、开发、升级等，不需要做太多的改动即可使用。

创建maven项目

在pom.xml中引入依赖包

xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0modelVersion>

    <groupId>com.example.springbootgroupId>
    <artifactId>springboot-mybatisartifactId>
    <version>0.0.1-SNAPSHOTversion>
    <packaging>jarpackaging>

    <name>springboot-mybatisname>
    <description>Demo project for Spring Bootdescription>

    <parent>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-parentartifactId>
        <version>1.5.12.RELEASEversion>
        <relativePath/> 
    parent>

    <properties>
        <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
        <java.version>1.7java.version>
        
        <mybatis-spring.version>1.3.2mybatis-spring.version>
        
        <mybatis-pagehelper.version>4.1.0mybatis-pagehelper.version>
    properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
        dependency>
        
        <dependency>
            <groupId>org.mybatis.spring.bootgroupId>
            <artifactId>mybatis-spring-boot-starterartifactId>
            <version>${mybatis-spring.version}version>
        dependency>
        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
            <scope>runtimescope>
        dependency>
        
        <dependency>
            <groupId>com.github.pagehelpergroupId>
            <artifactId>pagehelperartifactId>
            <version>${mybatis-pagehelper.version}version>
        dependency>
    dependencies>

    <build>
        <finalName>springboot-mybatisfinalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-maven-pluginartifactId>
            plugin>
        plugins>
    build>

project>

在src/main/resources/application.properties配置文件中增加数据库连接

#服务端口
#server.port=8088
#server.context-path=/springboot

#mysql数据连接
spring.datasource.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&serverTimezone=UTC
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=root
#spring.datasource.max-active=20
#spring.datasource.max-idle=8
#spring.datasource.min-idle=8
#spring.datasource.initial-size=20

#mybatis 配置
# 配置映射文件加载
mybatis.mapper-locations=classpath*:mapper/*.xml
# 实体类通过别名使用
#mybatis.type-aliases-package=com.example.springboot.mybatis.entity

编写实体类

package com.example.springboot.mybatis.entity;

public class User {
   private String id;

   private String username;

   private String password;

   private String email;

   /**
    * 是否可用(0禁用,1可用)
    */
   private Integer useable;

   /**
    * 创建时间
    */
   private String addtime;

   /**
    * 登陆时间
    */
   private String logintime;

   /**
    * 登陆IP
    */
   private String loginip;

编写dao类

package com.example.springboot.mybatis.dao;

import com.example.springboot.mybatis.entity.User;
import org.apache.ibatis.annotations.Mapper;
import java.util.List;

/**
 * 基于接口编程，通过mybatis与spring整合注入，在xml中编写sql语句
 */
@Mapper
public interface UserMapper {

   List queryList();

   void save(User user);

   void batchDelete(Integer[] ids);

   void update(User user);

}

编写dao对应xml配置文件

创建src/main/resources/mapper/UserMapper.xml文件，内容如下：

xml version="1.0" encoding="UTF-8"?>
 mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
   "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.springboot.mybatis.dao.UserMapper">

    <select id="queryList" resultType="com.example.springboot.mybatis.entity.User">
      SELECT u.id, u.username, u.password, u.email, u.useable, u.addtime, u.logintime, u.loginip FROM t_user u
   select>
   
   <select id="queryById" resultType="com.example.springboot.mybatis.entity.User">
      SELECT u.id, u.username, u.password, u.email, u.useable, u.addtime, u.logintime, u.loginip FROM t_user u where u.id = #{id}
   select>
   
   <insert id="save">
      insert into t_user(id,username, password, email, useable, addtime)
      values(#{id},#{username}, #{password}, #{email}, #{useable}, now())
   insert>
   
   <update id="update">
      update t_user set password = #{password}, email = #{email}, useable = #{useable} where id = #{id}
   update>
   
   <delete id="batchDelete">
      delete from m_user where id in
      <foreach collection="array" item="item" open="(" separator="," close=")">
         #{item}
      foreach>
   delete>
   
   
mapper>

编写service类

package com.example.springboot.mybatis.service;

import com.example.springboot.mybatis.dao.UserMapper;
import com.example.springboot.mybatis.entity.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import java.util.List;


/**
* @desc 通过mybatis xml配置文件读取数据
* @Author wangsh
* @date 2018/5/5 23:12
* @return 
*/
@Service
public class UserService2 {

   @Autowired
   private UserMapper userMapper;

   public List queryList() {
      List queryList = userMapper.queryList();
      return queryList;
   }

   public void batchDelete(Integer[] ids) {
      userMapper.batchDelete(ids);
   }

   // REQUIRED:表示必须又事物管理，如果没有事物，就创建一个事物
   @Transactional(propagation = Propagation.REQUIRED, isolation = Isolation.DEFAULT, timeout = 36000, rollbackFor = Exception.class)
   public void update(User user) {
      userMapper.update(user);
   }

   // REQUIRED:表示必须又事物管理，如果没有事物，就创建一个事物
   @Transactional(propagation = Propagation.REQUIRED, isolation = Isolation.DEFAULT, timeout = 36000, rollbackFor = Exception.class)
   public void save(User user) {
      userMapper.save(user);
   }
}

编写controller类

package com.example.springboot.mybatis.web;

import com.example.springboot.mybatis.entity.User;
import com.example.springboot.mybatis.service.UserService;
import com.example.springboot.mybatis.service.UserService2;
import com.example.springboot.mybatis.util.UUIDUtil;
import com.github.pagehelper.PageHelper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;

/**
 * @desc mybatis 操作数据库查询示例
 * @Author wangsh
 * @date 2018/5/5 23:18
 * @return
 */
@RestController
@RequestMapping("/user")
public class UserController {

  
   /**
    * 通过mybatis xml配置文件读取数据
    */
   @Autowired
   private UserService2 userService2;

   @RequestMapping("/queryList2")
   @ResponseBody
   public List queryList() {
      List queryList = userService2.queryList();
      return queryList;
   }

   @RequestMapping("/save2")
   @ResponseBody
   public User save2() {
      User user = new User();
      user.setId(UUIDUtil.getUUID());
      user.setUsername("lisi");
      user.setPassword("lisi");
      userService2.save(user);
      return user;
   }
}

编写启动服务类

package com.example.springboot.mybatis;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.transaction.annotation.EnableTransactionManagement;

/**
 * @desc mybatis启动服务
 * @Author wangsh
 * @date 2018/5/5 23:20
 * @return
 */
@SpringBootApplication
//如果mybatis中service实现类中加入@Transaction事务注解，需要此处添加该注解
@EnableTransactionManagement
//扫描的是mapper.xml中namespace指向值的包位置
@MapperScan("com.example.*")
public class SpringbootMybatisApplication {

   public static void main(String[] args) {
      SpringApplication.run(SpringbootMybatisApplication.class, args);
   }
}

启动服务测试

浏览器输入： http://localhost:8080//user/queryList2