spring boot 整合 mybatis-蒲公英云

1、在pom.xml中添加mysql和mybatis 的maven依赖

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>1.3.2</version>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>

2、在src/main/resources 目录下创建mybatis目录，并在下面创建mybatis-config.xml，同时创建一个mapper目录，用于存放sql映射文件

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mybatis-config.xml 内容如下：

<?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>
        <typeAlias alias="Integer" type="java.lang.Integer" />
        <typeAlias alias="Long" type="java.lang.Long" />
        <typeAlias alias="HashMap" type="java.util.HashMap" />
        <typeAlias alias="LinkedHashMap" type="java.util.LinkedHashMap" />
        <typeAlias alias="ArrayList" type="java.util.ArrayList" />
        <typeAlias alias="LinkedList" type="java.util.LinkedList" />
    </typeAliases>
</configuration>

3、在application.properties中添加数据库连接信息和 mybatis配置信息

#mysql
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/boot_v2?useUnicode=true&characterEncoding=utf8&characterSetResults=utf8&useSSL=false
spring.datasource.username=root
spring.datasource.password=root
#mybatis
#扫描指定路径下的实体，并用实体的简单名称作为别名
mybatis.type-aliases-package=com.ldy.bootv2.demo.entity
#自动扫描加载mybatis配置文件
mybatis.config-location=classpath:mybatis/mybatis-config.xml
#自动扫描加载Sql映射文件
mybatis.mapper-locations=classpath:mybatis/mapper/*.xml
#mapper目录下分多个模块时可以这样写
#mybatis.mapper-locations=classpath:mybatis/mapper/*/*.xml

4、创建数据库表

CREATE TABLE `user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `age` int(11) DEFAULT NULL,
  `name` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;
INSERT INTO `user` VALUES ('1', '20', 'zs'), ('2', '21', 'ls');

5、编写数据库表对应实体类：UserEntity.java

package com.ldy.bootv2.demo.entity;
import java.io.Serializable;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
@ApiModel
public class UserEntity implements Serializable {
    private static final long serialVersionUID = 1L;
        @ApiModelProperty(value="id，新建时不传，修改时传")
    private Integer id;
    @ApiModelProperty(value="名称")
    private String userName;
    @ApiModelProperty(value="年龄")
    private Integer userAge;
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public Integer getUserAge() {
        return userAge;
    }
    public void setUserAge(Integer userAge) {
        this.userAge = userAge;
    }
}

6、编写Dao层代码：UserMapper.java

package com.ldy.bootv2.demo.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import com.ldy.bootv2.demo.entity.UserEntity;
@Mapper
public interface UserMapper {
    List<UserEntity> getAll();
    UserEntity getOne(Integer id);
    int insert(UserEntity user);
    int update(UserEntity user);
    int delete(Integer id);
}

7、编写Controller：UserController

package com.ldy.bootv2.demo.controller;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.ldy.bootv2.demo.entity.UserEntity;
import com.ldy.bootv2.demo.mapper.UserMapper;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiParam;
@Api(tags = "用户信息管理接口-API")
@RestController
@RequestMapping("/user")
public class UserController {
    private static Logger logger = LoggerFactory.getLogger(UserController.class);
    @Autowired
    UserMapper userMapper;
    @GetMapping("/findAll")
    @ApiOperation("查询全部用户")
    public List<UserEntity> findAll() {
        logger.info("您调用了findAll接口");
        return userMapper.getAll();
    }
    @GetMapping("/getOne/{id}")
    @ApiOperation("根据ID查询用户")
    public UserEntity getOne(@ApiParam(value="用户id",required=true) @PathVariable("id") Integer id) {
        logger.info("您调用了getOne接口");
        return userMapper.getOne(id);
    }
    @PutMapping("/saveOrUpdate")
    @ApiOperation("新增或者修改用户")
    public String saveOrUpdate(@ModelAttribute UserEntity entity) {
        logger.info("您调用了saveOrUpdate接口");
        try {
            if(null == entity.getId()) {
                userMapper.insert(entity);
            }else {
                userMapper.update(entity);
            }
        } catch (Exception e) {
            logger.error("失败，原因：" + e.getMessage());
            return "error";
        }
        return "success";
    }
    @DeleteMapping("/delete/{id}")
    @ApiOperation("根据ID删除用户")
    public String deleteById(@ApiParam(value="用户id",required=true) @PathVariable("id") Integer id) {
        logger.info("您调用了delete接口");
        try {
            userMapper.delete(id);
        } catch (Exception e) {
            logger.error("失败，原因：" + e.getMessage());
            return "error";
        }
        return "success";
    }
}