SpringBoot SSMP整合案例

 简而言之：

 具体步骤如下：

1、创建新模块，并勾选web与sql技术集：

2、手动导入所需的额外依赖：

        
            com.baomidou
            mybatis-plus-boot-starter
            3.5.1
        

        
            com.alibaba
            druid-spring-boot-starter
            1.2.6
        

        
            org.projectlombok
            lombok
        

3、修改配置文件：

server:
  port: 80

spring:
  datasource:
    druid:
      driver-class-name: com.mysql.cj.jdbc.Driver
      url: jdbc:mysql://localhost:3306/test?rewriteBatchedStatements=true
      username: root
      password: mypassword

mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

4、表：

5、构建实体类：

@Data
@NoArgsConstructor
@AllArgsConstructor
@TableName("boot_book")
public class Book extends Model {

    @TableId(type = IdType.AUTO)
    private Integer id;
    private String type;
    private String name;
    private String description;

}

1、构建mapper接口：

@Mapper
public interface BookMapper extends BaseMapper {
}

2、配置文件中开启日志，并设置为标准输出：

mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

3、配置MP分页插件：

由于没有applicationContext.xml，配置方法与传统MP不同

package com.kvno.config;

import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MPConfig {

    //分页插件
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor(){
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor());
        return interceptor;
    }

}

4、编写测试类：

@SpringBootTest
public class MapperTestCase {
    @Autowired
    BookMapper bookMapper;

    @Test
    public void testGetById() {
        System.out.println(bookMapper.selectById(1));
    }

    @Test
    public void testInsert() {
        Book book = new Book();
        book.setName("海绵宝宝");
        book.setType("CH");
        book.setDescription("yellow");

        boolean result = book.insert();
        System.out.println(result);
    }

    @Test
    public void testUpdate() {
        Book book = new Book();
        book.setId(3);
        book.setName("海绵宝宝");
        book.setType("CH");
        book.setDescription("square");

        boolean result = book.updateById();
        System.out.println(result);
    }

    @Test
    public void testGetAll() {
        List books = bookMapper.selectList(null);
        for (Book book: books) {
            System.out.println(book);
        }
    }

    @Test
    public void testGetPage() {
        IPage page = new Page<>(1,1);
        bookMapper.selectPage(page,null);
        System.out.println(page.getCurrent());
        System.out.println(page.getSize());
        System.out.println(page.getTotal());
        System.out.println(page.getPages());
        System.out.println(page.getRecords());
    }

    @Test
    public void testWrapper() {
        QueryWrapper userQueryWrapper = new QueryWrapper<>();
        userQueryWrapper.eq("type","CH");
        bookMapper.selectList(userQueryWrapper);
    }
}

 1、定义接口并编写实现类：

public interface BookService {
    Boolean insert(Book book);
    Boolean update(Book book);
    Boolean delete(Integer id);
    Book getById(Integer id);
    List getAll();
    IPage getPage(Integer currentpage,Integer sizePage);
}

@Service
public class BookServiceImpl implements BookService {
    @Autowired
    private BookMapper bookMapper;

    @Override
    public Boolean insert(Book book) {
        return book.insert();
    }

    @Override
    public Boolean update(Book book) {
        return book.updateById();
    }

    @Override
    public Boolean delete(Integer id) {
        return bookMapper.deleteById(id) > 0;
    }

    @Override
    public Book getById(Integer id) {
        return bookMapper.selectById(id);
    }

    @Override
    public List getAll() {
        return bookMapper.selectList(null);
    }

    @Override
    public IPage getPage(Integer currentpage, Integer sizePage) {
        IPage page = new Page(currentpage,sizePage);
        return bookMapper.selectPage(page,null);
    }

}

2、编写测试类：

@SpringBootTest
public class ServiceTestCase {
    @Autowired
    private BookService bookService;

    @Test
    void testGetById() {
        System.out.println(bookService.getById(1));
    }

    @Test
    public void testInsert() {
        Book book = new Book();
        book.setName("test");
        book.setType("CH");
        book.setDescription("service");
        bookService.insert(book);
    }

    @Test
    void testUpdate(){
        Book book = new Book();
        book.setId(4);
        book.setDescription("测试数据service");
        bookService.update(book);
    }

    @Test
    void testDelete(){
        bookService.delete(4);
    }

    @Test
    void testGetAll(){
        bookService.getAll();
    }

    @Test
    public void testGetPage() {
        IPage page = bookService.getPage(2,1);
        System.out.println(page.getCurrent());
        System.out.println(page.getSize());
        System.out.println(page.getTotal());
        System.out.println(page.getPages());
        System.out.println(page.getRecords());
    }
}

• 使用MyBatisPlus提供有业务层通用接口（ISerivce）快速开发service接口，使用业务层通用实现类（ServiceImpl)快速开发service实现类；

• 在通用类基础上做功能重载或功能追加；

• 可以编写额外方法，注意重载时不要覆盖原始操作，避免原始提供的功能丢失。

与MP提供的BaseMapper类似，封装了各种业务层方法。简化了开发过程。

1、接口与实现类：

public interface IBookService extends IService {
    boolean saveBook(Book book);
}

@Service
public class QuickBookServiceImp extends ServiceImpl implements IBookService {
    @Autowired
    private BookMapper bookMapper;

    @Override
    public boolean saveBook(Book book) {
        return bookMapper.insert(book) > 0;
    }
}

2、测试：

@SpringBootTest
public class QuickServiceTestCase {
    @Autowired
    private IBookService bookService;

    @Test
    void testGetById() {
        System.out.println(bookService.getById(1));
    }

    @Test
    public void testSave() {
        Book book = new Book();
        book.setName("test");
        book.setType("CH");
        book.setDescription("service");
        bookService.save(book);
    }

    @Test
    void testUpdate(){
        Book book = new Book();
        book.setId(4);
        book.setDescription("测试数据service");
        bookService.updateById(book);
    }

    @Test
    void testDelete(){
        bookService.removeById(4);
    }

    @Test
    void testGetAll(){
        bookService.list();
    }

    @Test
    public void testGetPage() {
        IPage page = new Page(2,1);
        bookService.page(page);
        System.out.println(page.getCurrent());
        System.out.println(page.getSize());
        System.out.println(page.getTotal());
        System.out.println(page.getPages());
        System.out.println(page.getRecords());
    }
}

• 基于Restful进行表现层接口开发
• 使用Postman测试接口功能

1、编写controller：

注：@RequestBody：接收前端传递给后端的请求体中的数据。

//@RestController
@RequestMapping("/books")
public class BookControllerTest {
    @Autowired
    private IBookService bookService;

    @GetMapping
    public List getAll() {
        return bookService.list();
    }

    @PostMapping
    public Boolean save(@RequestBody Book book) { //@RequestBody
        return bookService.save(book);
    }

    @PutMapping
    public Boolean update(@RequestBody Book book) {
        return bookService.updateById(book);
    }

    @DeleteMapping("/{id}")
    public Boolean delete(@PathVariable(value = "id") Integer id) {
        return bookService.removeById(id);
    }

    @GetMapping("/{id}")
    public Book getById(@PathVariable(value = "id") Integer id) {
        return bookService.getById(id);
    }

    @GetMapping("/{currentPage}/{pageSize}")
    public IPage getPage(@PathVariable int currentPage, @PathVariable int pageSize){
        IPage page = new Page(currentPage,pageSize);
        return bookService.page(page);
    }

}

2、测试：

返回数据类型不一致会给前端带来不便：

 单纯地封装数据又会造成误解，如数据为null时：

 故采用以下格式：

优点：

示例：

1、设计表现层返回结果的模型类，用于后端与前端进行数据格式统一，也称为前后端数据协议：

@Data
@NoArgsConstructor
@AllArgsConstructor
public class R { //Result
    private Boolean flag;
    private Object data;

    public R(Boolean flag) {
        this.flag = flag;
    }
}

2、编写controller：

@RestController
@RequestMapping("/books")
public class BookController {
    @Autowired
    private IBookService bookService;

    @GetMapping
    public R getAll() {
        return new R(true,bookService.list());
    }

    @PostMapping
    public R save(@RequestBody Book book) { //@RequestBody:接收前端传递给后端的请求体中的数据
        return new R(bookService.save(book));
    }

    @PutMapping
    public R update(@RequestBody Book book) {
        return new R(bookService.updateById(book));
    }

    @DeleteMapping("/{id}")
    public R delete(@PathVariable(value = "id") Integer id) {
        return new R(bookService.removeById(id));
    }

    @GetMapping("/{id}")
    public R getById(@PathVariable(value = "id") Integer id) {
        return new R(true,bookService.getById(id));
    }

    @GetMapping("/{currentPage}/{pageSize}")
    public R getPage(@PathVariable int currentPage, @PathVariable int pageSize){
        return new R(true,bookService.page(new Page(currentPage,pageSize)));
    }

}

3、测试：

1、使用注解@RestControllerAdvice定义SpringMVC异常处理器，异常处理器必须被扫描加载，否则无法生效；对异常消息进行统一处理，出现异常后返回指定类型：

@RestControllerAdvice
public class ProjectExceptionAdvice {

    //拦截所有的异常信息
    @ExceptionHandler(Exception.class)
    public R doException(Exception ex){
        //记录日志
        //通知运维
        //通知开发
        ex.printStackTrace(); //控制台仍然要显示异常
        return new R(false,"服务器故障，请稍后再试！");
    }

}

2、修改表现层返回结果的模型类，封装出现异常后对应的信息：

@Data
@NoArgsConstructor
@AllArgsConstructor
public class R { //Result
    private Boolean flag;
    private Object data;
    private String msg;

    public R(Boolean flag) {
        this.flag = flag;
    }

    public R(Boolean flag,Object data) {
        this.flag = flag;
        this.data = data;
    }

    public R(Boolean flag,String msg) {
        this.flag = flag;
        this.msg = msg;
    }
}