1. 程式人生 > >SpringBoot(五):SpringBoot整合MyBatis

SpringBoot(五):SpringBoot整合MyBatis

怎麼說了,寫部落格雖然是一件很費時間的事情,而且還是個菜鳥,但是如果寫的東西能夠幫助到別人,還是值得開心的。

回顧:

上篇寫了JdbcTemplate,但是想到使用Mybatis,JPA的人估計不少,所以這篇寫一下SpringBoot整合Mybatis,JPA的話以後有時間再弄,因為自己也沒用過。

一、資料準備

其實還是上篇的,以防有人是直接看這篇的,就還是貼出來吧。

CREATE TABLE `tb_user` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT 'ID',
  `username` varchar(50) NOT NULL
COMMENT '使用者名稱', `age` int(11) NOT NULL COMMENT '年齡', `ctm` datetime NOT NULL COMMENT '建立時間', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8
INSERT INTO `db_test`.`tb_user` (`username`, `age`, `ctm`) VALUES('張三', '18', NOW()) ;
INSERT INTO `db_test`.`tb_user` (`username`, `age`, `ctm`
) VALUES('李四', '20', NOW()) ;
INSERT INTO `db_test`.`tb_user` (`username`, `age`, `ctm`) VALUES('王五', '19', NOW()) ;

二、引入依賴

<!-- Spring-Mybatis -->
		<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency> <!-- MySQL --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency>

另外web依賴也需要,因為我們採用MVC模式。

<!-- Add typical dependencies for a web application -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

三、資料庫配置檔案

spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/db_user
    username: root
    password: root

四、程式碼

最開始使用mybati比較麻煩,各種配置檔案、實體類、dao層對映關聯、還有一大推其它配置。當然mybatis也發現了這種弊端,初期開發了generator可以根據表結果自動生產實體類、配置檔案和dao層程式碼,可以減輕一部分開發量;後期也進行了大量的優化可以使用註解了。

於是兩種使用方式都介紹一下,一、無配置註解版 二、配置檔案版

1.無配置檔案註解版

加入配置檔案

mybatis:
  type-aliases-package: cn.saytime.bean

這裡寫圖片描述

實體類User.class

package cn.saytime.bean;

import java.util.Date;

/**
 * @ClassName cn.saytime.bean.User
 * @Description
 * @date 2017-07-04 22:47:28
 */
public class User {

	private int id;
	private String username;
	private int age;
	private Date ctm;

	public User() {
	}

	public User(String username, int age) {
		this.username = username;
		this.age = age;
		this.ctm = new Date();
	}

	// Getter、Setter
}

UserMapper.class

package cn.saytime.mapper;

import cn.saytime.bean.User;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import java.util.List;

// @Mapper 這裡可以使用@Mapper註解,但是每個mapper都加註解比較麻煩,所以統一配置@MapperScan在掃描路徑在application類中
public interface UserMapper {

	@Select("SELECT * FROM tb_user WHERE id = #{id}")
	User getUserById(Integer id);

	@Select("SELECT * FROM tb_user")
	public List<User> getUserList();

	@Insert("insert into tb_user(username, age, ctm) values(#{username}, #{age}, now())")
	public int add(User user);

	@Update("UPDATE tb_user SET username = #{user.username} , age = #{user.age} WHERE id = #{id}")
	public int update(@Param("id") Integer id, @Param("user") User user);

	@Delete("DELETE from tb_user where id = #{id} ")
	public int delete(Integer id);
}

UserService.class

package cn.saytime.service;

import cn.saytime.bean.User;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * @ClassName cn.saytime.service.UserService
 * @Description
 */
public interface UserService {

	User getUserById(Integer id);

	public List<User> getUserList();

	public int add(User user);

	public int update(Integer id, User user);

	public int delete(Integer id);
}

UserServiceimpl.class

package cn.saytime.service.impl;

import cn.saytime.bean.User;
import cn.saytime.mapper.UserMapper;
import cn.saytime.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * @ClassName cn.saytime.service.impl.UserServiceImpl
 * @Description
 */
@Service
public class UserServiceImpl implements UserService {

	@Autowired
	private UserMapper userMapper;

	@Override
	public User getUserById(Integer id) {
		return userMapper.getUserById(id);
	}

	@Override
	public List<User> getUserList() {
		return userMapper.getUserList();
	}

	@Override
	public int add(User user) {
		return userMapper.add(user);
	}

	@Override
	public int update(Integer id, User user) {
		return userMapper.update(id, user);
	}

	@Override
	public int delete(Integer id) {
		return userMapper.delete(id);
	}
}

JsonResult.class 通用json返回類

package cn.saytime.bean;

public class JsonResult {

	private String status = null;

	private Object result = null;

	public JsonResult status(String status) {
		this.status = status;
		return this;
	}

	// Getter Setter
}

UserController.class(Restful風格

package cn.saytime.web;

import cn.saytime.bean.JsonResult;
import cn.saytime.bean.User;
import cn.saytime.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

/**
 * @ClassName cn.saytime.web.UserController
 * @Description
 * @date 2017-07-04 22:46:14
 */
@RestController
public class UserController {

	@Autowired
	private UserService userService;

	/**
	 * 根據ID查詢使用者
	 * @param id
	 * @return
	 */
	@RequestMapping(value = "user/{id}", method = RequestMethod.GET)
	public ResponseEntity<JsonResult> getUserById (@PathVariable(value = "id") Integer id){
		JsonResult r = new JsonResult();
		try {
			User user = userService.getUserById(id);
			r.setResult(user);
			r.setStatus("ok");
		} catch (Exception e) {
			r.setResult(e.getClass().getName() + ":" + e.getMessage());
			r.setStatus("error");
			e.printStackTrace();
		}
		return ResponseEntity.ok(r);
	}

	/**
	 * 查詢使用者列表
	 * @return
	 */
	@RequestMapping(value = "users", method = RequestMethod.GET)
	public ResponseEntity<JsonResult> getUserList (){
		JsonResult r = new JsonResult();
		try {
			List<User> users = userService.getUserList();
			r.setResult(users);
			r.setStatus("ok");
		} catch (Exception e) {
			r.setResult(e.getClass().getName() + ":" + e.getMessage());
			r.setStatus("error");
			e.printStackTrace();
		}
		return ResponseEntity.ok(r);
	}

	/**
	 * 新增使用者
	 * @param user
	 * @return
	 */
	@RequestMapping(value = "user", method = RequestMethod.POST)
	public ResponseEntity<JsonResult> add (@RequestBody User user){
		JsonResult r = new JsonResult();
		try {
			int orderId = userService.add(user);
			if (orderId < 0) {
				r.setResult(orderId);
				r.setStatus("fail");
			} else {
				r.setResult(orderId);
				r.setStatus("ok");
			}
		} catch (Exception e) {
			r.setResult(e.getClass().getName() + ":" + e.getMessage());
			r.setStatus("error");

			e.printStackTrace();
		}
		return ResponseEntity.ok(r);
	}

	/**
	 * 根據id刪除使用者
	 * @param id
	 * @return
	 */
	@RequestMapping(value = "user/{id}", method = RequestMethod.DELETE)
	public ResponseEntity<JsonResult> delete (@PathVariable(value = "id") Integer id){
		JsonResult r = new JsonResult();
		try {
			int ret = userService.delete(id);
			if (ret < 0) {
				r.setResult(ret);
				r.setStatus("fail");
			} else {
				r.setResult(ret);
				r.setStatus("ok");
			}
		} catch (Exception e) {
			r.setResult(e.getClass().getName() + ":" + e.getMessage());
			r.setStatus("error");

			e.printStackTrace();
		}
		return ResponseEntity.ok(r);
	}

	/**
	 * 根據id修改使用者資訊
	 * @param user
	 * @return
	 */
	@RequestMapping(value = "user/{id}", method = RequestMethod.PUT)
	public ResponseEntity<JsonResult> update (@PathVariable("id") Integer id, @RequestBody User user){
		JsonResult r = new JsonResult();
		try {
			int ret = userService.update(id, user);
			if (ret < 0) {
				r.setResult(ret);
				r.setStatus("fail");
			} else {
				r.setResult(ret);
				r.setStatus("ok");
			}
		} catch (Exception e) {
			r.setResult(e.getClass().getName() + ":" + e.getMessage());
			r.setStatus("error");

			e.printStackTrace();
		}
		return ResponseEntity.ok(r);
	}

}

Application.java

package cn.saytime;

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

@SpringBootApplication
@MapperScan("cn.saytime.mapper")
public class SpringbootMybaitsApplication {

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

使用PostMan通過測試。

2.配置檔案版

加入配置檔案

mybatis:
  mapper-locations: classpath:mybatis/mapper/*.xml
  config-location: classpath:mybatis/mybatis-config.xml

專案目錄結構:

這裡寫圖片描述

程式碼部分,相比於上面那種方式,改變的只有配置檔案以及下面幾個部分。

UserMapper.class

package cn.saytime.mapper;

import cn.saytime.bean.User;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import org.springframework.stereotype.Repository;

import java.util.List;

/**
 * @ClassName cn.saytime.mapper.UesrMapper
 * @Description
 */
@Repository
public interface UserMapper {

	User getUserById(Integer id);

	public List<User> getUserList();

	public int add(User user);

	public int update(@Param("id") Integer id, @Param("user") User user);

	public int delete(Integer id);
}

mybatis-config.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>
    <typeAliases>
    </typeAliases>
</configuration>

userMapper.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="cn.saytime.mapper.UserMapper" >
    <resultMap id="BaseResultMap" type="cn.saytime.bean.User" >
        <id column="id" property="id" jdbcType="INTEGER" />
        <result column="username" property="username" jdbcType="VARCHAR" />
        <result column="age" property="age" jdbcType="INTEGER" />
        <result column="ctm" property="ctm" jdbcType="TIMESTAMP"/>
    </resultMap>

    <sql id="Base_Column_List" >
        id, username, age, ctm
    </sql>

    <select id="getUserList" resultMap="BaseResultMap"  >
        SELECT
        <include refid="Base_Column_List" />
        FROM tb_user
    </select>

    <select id="getUserById" parameterType="java.lang.Integer" resultMap="BaseResultMap" >
        SELECT
        <include refid="Base_Column_List" />
        FROM tb_user
        WHERE id = #{id}
    </select>

    <insert id="add" parameterType="cn.saytime.bean.User" >
        INSERT INTO
        tb_user
        (username,age,ctm)
        VALUES
        (#{username}, #{age}, now())
    </insert>

    <update id="update" parameterType="java.util.Map" >
        UPDATE
        tb_user
        SET
        username = #{user.username},age = #{user.age}
        WHERE
        id = #{id}
    </update>

    <delete id="delete" parameterType="java.lang.Integer" >
        DELETE FROM
        tb_user
        WHERE
        id = #{id}
    </delete>
</mapper>

上面這種方式也使用PostMan通過測試。

五、簡要說明

不知道大家有沒有注意到一點,就是引入Springboot-mybatis依賴的時候,並不是spring官方的starter,往常的springboot整合的依賴,比如web,redis等,groupId以及artifactId的地址如下:

<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

而這裡是mybatis為spring提供的starter依賴,所以依賴地址是:

<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>1.3.0</version>
		</dependency>

而且值得注意的是,這裡必須要指定版本號,往常我們使用springboot之所以不需要指定版本號,是因為我們引入的Maven Parent 中指定了SpringBoot的依賴,SpringBoot官方依賴Pom檔案中已經指定了它自己整合的第三方依賴的版本號,對於Mybatis,Spring官方並沒有提供自己的starter,所以必須跟正常的maven依賴一樣,要加版本號。