Spring Boot 知识笔记（整合Mybatis）

一、pom.xml中添加相关依赖

<!-- 引入starter-->
                    <dependency>
                        <groupId>org.mybatis.spring.boot</groupId>
                        <artifactId>mybatis-spring-boot-starter</artifactId>
                        <version>1.3.2</version>
                        <scope>runtime</scope>
                    </dependency>

             <!-- MySQL的JDBC驱动包    -->
                     <dependency>
                        <groupId>mysql</groupId>
                        <artifactId>mysql-connector-java</artifactId>
                        <scope>runtime</scope>
                    </dependency>
            <!-- 引入第三方数据源 -->
                    <dependency>
                        <groupId>com.alibaba</groupId>
                        <artifactId>druid</artifactId>
                        <version>1.1.6</version>
                    </dependency>

二、在application.properties中添加Mybatis的配置

            #mybatis.type-aliases-package=net.xdclass.base_project.domain
            #可以自动识别
            #spring.datasource.driver-class-name =com.mysql.jdbc.Driver

            spring.datasource.url=jdbc:mysql://localhost:3306/movie?useUnicode=true&characterEncoding=utf-8
            spring.datasource.username =root
            spring.datasource.password =password
            #如果不使用默认的数据源 （com.zaxxer.hikari.HikariDataSource）
            spring.datasource.type =com.alibaba.druid.pool.DruidDataSource

三、启动文件中加入注解，以便可以自动扫描包里面所有的Mapper文件

四、本地mysql数据库中创建movie库，创建对应的表

//创建表的SQL如下
CREATE TABLE `user` (
              `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
              `name` varchar(128) DEFAULT NULL COMMENT '名称',
              `phone` varchar(16) DEFAULT NULL COMMENT '用户手机号',
              `create_time` datetime DEFAULT NULL COMMENT '创建时间',
              `age` int(4) DEFAULT NULL COMMENT '年龄',
              PRIMARY KEY (`id`)
            ) ENGINE=InnoDB AUTO_INCREMENT=18 DEFAULT CHARSET=utf8;

五、创建一个domain类

package net.Eleven.demo.domain;

import java.util.Date;

public class UserNew {
    private int id;
    private String name;
    private String phone;
    private int age;
    private Date creatTime;

    public int getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public String getPhone() {
        return phone;
    }

    public int getAge() {
        return age;
    }

    public Date getCreatTime() {
        return creatTime;
    }

    public void setId(int id) {
        this.id = id;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public void setCreatTime(Date creatTime) {
        this.creatTime = creatTime;
    }

}

六、创建Mapper，访问数据库的接口

package net.Eleven.demo.Mapper;

import net.Eleven.demo.domain.UserNew;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Options;

/**
 * 功能描述：访问数据库的接口，相当于dao层
 * @author Eleven
 */

public interface UserMapper {

    //推荐使用#{}取值，不要用${},因为存在注入的风险
    @Insert("INSERT INTO user(name,phone,create_time,age) VALUES(#{name},#{phone},#{creatTime},#{age})")  //VALUESDE 的值必须与domain中的字段一一对应。
    @Options(useGeneratedKeys = true,keyProperty = "id",keyColumn = "id") //keyProperty java对象的属性；keyColumn表示数据库的字段
    int insert(UserNew userNew);
}

七、创建Service 和Impl

package net.Eleven.demo.Service;

import net.Eleven.demo.domain.UserNew;

public interface UserService {
    public int add(UserNew userNew);
}

package net.Eleven.demo.Service.impl;

import net.Eleven.demo.Mapper.UserMapper;
import net.Eleven.demo.Service.UserService;
import net.Eleven.demo.domain.UserNew;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service   //不要忘了注解
public class UserServiceImpl implements UserService {
    @Autowired
    private UserMapper userMapper;

    @Override
    public int add(UserNew userNew) {
        userMapper.insert(userNew);
        int id = userNew.getId();
        return id;

    }
}

八、创建Controller

package net.Eleven.demo.controller;

import net.Eleven.demo.Service.UserService;
import net.Eleven.demo.domain.JsonData;
import net.Eleven.demo.domain.UserNew;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

@RestController
@RequestMapping("/api/sql/user")
public class UserController {
    @Autowired
    private UserService userService;
    @GetMapping("add")
    public Object add(){
        UserNew userNew = new UserNew();
        userNew.setAge(11);
        userNew.setCreatTime(new Date());
        userNew.setName("Eleven");
        userNew.setPhone("18211111111");
        int id = userService.add(userNew);
        return JsonData.buildSuccess(id);
    }

}

九、创建第八步使用的JsonData类，以便更好的展示返回的数据

package net.Eleven.demo.domain;

import java.io.Serializable;

public class JsonData implements Serializable {

    /**
     *
     */
    private static final long serialVersionUID = 1L;

    private Integer code; // 状态码 0 表示成功，1表示处理中，-1表示失败
    private Object data; // 数据
    private String msg;// 描述

    public JsonData() {
    }

    public JsonData(Integer code, Object data, String msg) {
        this.code = code;
        this.data = data;
        this.msg = msg;
    }
    public JsonData(int code, Object data) {
        super();
        this.code = code;
        this.data = data;
    }

    // 成功，传入数据
    public static JsonData buildSuccess() {
        return new JsonData(0, null, null);
    }

    // 成功，传入数据
    public static JsonData buildSuccess(Object data) {
        return new JsonData(0, data, null);
    }

    // 失败，传入描述信息
    public static JsonData buildError(String msg) {
        return new JsonData(-1, null, msg);
    }

    // 失败，传入描述信息,状态码
    public static JsonData buildError(String msg, Integer code) {
        return new JsonData(code, null, msg);
    }

    // 成功，传入数据,及描述信息
    public static JsonData buildSuccess(Object data, String msg) {
        return new JsonData(0, data, msg);
    }

    // 成功，传入数据,及状态码
    public static JsonData buildSuccess(Object data, int code) {
        return new JsonData(code, data, null);
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    @Override
    public String toString() {
        return "JsonData [code=" + code + ", data=" + data + ", msg=" + msg
                + "]";
    }

}

十、执行结果

十一、遇到的报错

错误提示:

Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: The server time zone value '�й���׼ʱ��' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.

解决办法;

在连接字符串后面加上?serverTimezone=UTC

其中UTC是统一标准世界时间。

完整的连接字符串示例：jdbc:mysql://localhost:3306/test?serverTimezone=UTC

或者还有另一种选择：jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=UTF-8，这个是解决中文乱码输入问题，当然也可以和上面的一起结合：jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC