Spring Boot 揭秘与实战（二）数据存储篇 - MyBatis整合

本文讲解Spring Boot基础下，如何整合MyBatis框架，编写数据访问。
原文地址：Spring Boot 揭秘与实战（二）数据存储篇 - MyBatis整合
博客地址：blog.720ui.com/

环境依赖

修改 POM 文件，添加mybatis-spring-boot-starter依赖。值得注意的是，可以不添加spring-boot-starter-jdbc。因为，mybatis-spring-boot-starter依赖中存在spring-boot-starter-jdbc。

<dependency>
  <groupId>org.mybatis.spring.boot</groupId>
  <artifactId>mybatis-spring-boot-starter</artifactId>
  <version>1.1.1</version>
</dependency>

添加mysql依赖。

<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>5.1.35</version>
</dependency>
<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>druid</artifactId>
  <version>1.0.14</version>
</dependency>

数据源

方案一使用 Spring Boot 默认配置

在 src/main/resources/application.properties 中配置数据源信息。

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/springboot_db?useUnicode = true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull
spring.datasource.username=root
spring.datasource.password=root

方案二手动创建

在 src/main/resources/config/source.properties 中配置数据源信息。

# mysql
source.driverClassName = com.mysql.jdbc.Driver
source.url = jdbc:mysql://localhost:3306/springboot_db?useUnicode = true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull
source.username = root
source.password = root

通过 Java Config 创建 dataSource 和jdbcTemplate 。

@Configuration
@EnableTransactionManagement
@PropertySource(value = {"classpath:config/source.properties"})
public class BeanConfig {

    @Autowired
    private Environment env;

    @Bean(destroyMethod = "close")
    public DataSource dataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(env.getProperty("source.driverClassName").trim());
        dataSource.setUrl(env.getProperty("source.url").trim());
        dataSource.setUsername(env.getProperty("source.username").trim());
        dataSource.setPassword(env.getProperty("source.password").trim());
        return dataSource;
    }

@Bean
    public JdbcTemplate jdbcTemplate() {
        JdbcTemplate jdbcTemplate = new JdbcTemplate();
        jdbcTemplate.setDataSource(dataSource());
        return jdbcTemplate;
    }
}

脚本初始化

先初始化需要用到的SQL脚本。

CREATE DATABASE /*!32312 IF NOT EXISTS*/`springboot_db` /*!40100 DEFAULT CHARACTER SET utf8 */;

USE `springboot_db`;

DROP TABLE IF EXISTS `t_author`;

CREATE TABLE `t_author` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT COMMENT '用户ID',
  `real_name` varchar(32) NOT NULL COMMENT '用户名称',
  `nick_name` varchar(32) NOT NULL COMMENT '用户匿名',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

MyBatis整合

方案一通过注解的方式

实体对象

public class Author {
    private Long id;
    @JSONField(name="real_name")
    private String realName;
    @JSONField(name="nick_name")
    private String nickName;

    // SET和GET方法
}

DAO相关

@Mapper
public interface AuthorMapper {

    @Insert("insert into t_author(real_name, nick_name) values(#{real_name}, #{nick_name})")
    int add(@Param("realName") String realName, @Param("nickName") String nickName);

    @Update("update t_author set real_name = #{real_name}, nick_name = #{nick_name} where id = #{id}")
    int update(@Param("real_name") String realName, @Param("nick_name") String nickName, @Param("id") Long id);

    @Delete("delete from t_author where id = #{id}")
    int delete(Long id);

    @Select("select id, real_name as realName, nick_name as nickName from t_author where id = #{id}")
    Author findAuthor(@Param("id") Long id);

    @Select("select id, real_name as realName, nick_name as nickName from t_author")
    List<Author> findAuthorList();
}

Service相关

@Service
public class AuthorService {
    @Autowired
    private AuthorMapper authorMapper;

    public int add(String realName, String nickName) {
        return this.authorMapper.add(realName, nickName);
    }
    public int update(String realName, String nickName, Long id) {
        return this.authorMapper.update(realName, nickName, id);      
    }
    public int delete(Long id) {
        return this.authorMapper.delete(id);
    }
    public Author findAuthor(Long id) {
        return this.authorMapper.findAuthor(id);
    }
    public List<Author> findAuthorList() {
        return this.authorMapper.findAuthorList();
    }
}

Controller相关

为了展现效果，我们先定义一组简单的　RESTful API 接口进行测试。

@RestController("mybatis.authorController")
@RequestMapping(value="/data/mybatis/author")
@MapperScan("com.lianggzone.springboot.action.data.mybatis.dao")
public class AuthorController {

  @Autowired
  private AuthorService authorService;
  /**
   * 查询用户列表
   */
  @RequestMapping(method = RequestMethod.GET)
  public Map<String,Object> getAuthorList(HttpServletRequest request) {        
    List<Author> authorList = this.authorService.findAuthorList();
    Map<String,Object> param = new HashMap<String,Object>();
    param.put("total", authorList.size());
    param.put("rows", authorList);
    return param;
  }
  /**
   * 查询用户信息
   */
  @RequestMapping(value = "/{userId:\\d+}", method = RequestMethod.GET)
  public Author getAuthor(@PathVariable Long userId, HttpServletRequest request) {
    Author author = this.authorService.findAuthor(userId);
    if(author == null){
        throw new RuntimeException("查询错误");
    }
    return author;
  }

  /**
   * 新增方法
   */
  @RequestMapping(method = RequestMethod.POST)
  public void add(@RequestBody JSONObject jsonObject) {
    String userId = jsonObject.getString("user_id");
    String realName = jsonObject.getString("real_name");
    String nickName = jsonObject.getString("nick_name");

    try{
        this.authorService.add(realName, nickName);
    }catch(Exception e){
        e.printStackTrace();
        throw new RuntimeException("新增错误");
    }
  }
  /**
   * 更新方法
   */
  @RequestMapping(value = "/{userId:\\d+}", method = RequestMethod.PUT)
    public void update(@PathVariable Long userId, @RequestBody JSONObject jsonObject) {
    Author author = this.authorService.findAuthor(userId);
    String realName = jsonObject.getString("real_name");
    String nickName = jsonObject.getString("nick_name");

    try{
        this.authorService.update(realName, nickName, author.getId());
    }catch(Exception e){
        e.printStackTrace();
        throw new RuntimeException("更新错误");
    } 
  }
  /**
   * 删除方法
   */
  @RequestMapping(value = "/{userId:\\d+}", method = RequestMethod.DELETE)
    public void delete(@PathVariable Long userId) {
    try{
        this.authorService.delete(userId);
    }catch(Exception e){
        throw new RuntimeException("删除错误");
    }
  }
}

方案二通过配置文件的方式

实体对象

public class Author {
    private Long id;
    @JSONField(name="real_name")
    private String realName;
    @JSONField(name="nick_name")
    private String nickName;

    // SET和GET方法
}

配置相关

在 src/main/resources/mybatis/AuthorMapper.xml 中配置数据源信息。

<?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.lianggzone.springboot.action.data.mybatis.dao.AuthorMapper2">

    <!-- type为实体类Student，包名已经配置，可以直接写类名 -->
    <resultMap id="authorMap" type="Author">
        <id property="id" column="id" />
        <result property="realName" column="real_name" />
        <result property="nickName" column="nick_name" />
    </resultMap>

    <select id="findAuthor" resultMap="authorMap" resultType="Author">
        select id, real_name, nick_name from t_author where id = #{id}
    </select>
</mapper>

在 src/main/resources/application.properties 中配置数据源信息。

mybatis.mapper-locations=classpath*:mybatis/*Mapper.xml
mybatis.type-aliases-package=com.lianggzone.springboot.action.data.mybatis.entity

DAO相关

public interface AuthorMapper2 { 
    Author findAuthor(@Param("id") Long id); 
}

Service相关

@Service
public class AuthorService2 {
    @Autowired
    private AuthorMapper2 authorMapper;

    public Author findAuthor(Long id) {
        return this.authorMapper.findAuthor(id);
    }
}

Controller相关

为了展现效果，我们先定义一组简单的　RESTful API 接口进行测试。

@RestController("mybatis.authorController2")
@RequestMapping(value="/data/mybatis/author2")
@MapperScan("com.lianggzone.springboot.action.data.mybatis.dao")
public class AuthorController2 { 
  @Autowired
  private AuthorService2 authorService; 
  /**
   * 查询用户信息
   */
  @RequestMapping(value = "/{userId:\\d+}", method = RequestMethod.GET)
  public Author getAuthor(@PathVariable Long userId, HttpServletRequest request) {
    Author author = this.authorService.findAuthor(userId);
    if(author == null){
        throw new RuntimeException("查询错误");
    }
    return author;
  }
}

总结

上面这个简单的案例，让我们看到了 Spring Boot 整合 MyBatis 框架的大概流程。那么，复杂的场景，大家可以参考使用一些比较成熟的插件，例如com.github.pagehelper、mybatis-generator-maven-plugin等。

源代码

相关示例完整代码： springboot-action

（完）

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Spring Boot 揭秘与实战（二） 数据存储篇 - MyBatis整合

环境依赖

数据源

方案一 使用 Spring Boot 默认配置

方案二 手动创建

脚本初始化

MyBatis整合

方案一 通过注解的方式

实体对象

DAO相关

Service相关

Controller相关

方案二 通过配置文件的方式

实体对象

配置相关

DAO相关

Service相关

Controller相关

总结

源代码

Spring Boot 揭秘与实战（二）数据存储篇 - MyBatis整合

方案一使用 Spring Boot 默认配置

方案二手动创建

方案一通过注解的方式

方案二通过配置文件的方式