基于SpringBoot的SSMP整合案例

简介：SSMP(Spring+SpringMVC+MyBatis)，通过SpringBoot整合SSMP来完成增删改查案例。

功能开发模块

1. 实体类开发————使用Lombok快速制作实体类
2. Dao开发————整合MyBatisPlus，制作数据层测试
3. Service开发————基于MyBatisPlus进行增量开发，制作业务层测试类
4. Controller开发————基于Restful开发，使用PostMan测试接口功能
5. Controller开发————前后端开发协议制作
6. 页面开发————基于VUE+ElementUI制作，前后端联调，页面数据处理，页面消息处理
   • 列表
   • 新增
   • 修改
   • 删除
   • 分页
   • 查询
7. 项目异常处理
8. 按条件查询————页面功能调整、Controller修正功能、Service修正功能

创建模块

数据层(Dao层)操作

创建项目

pom.xml

需要添加mybatis-plus的配置文件。

4.0.0org.springframework.bootspring-boot-starter-parent2.7.6 com.exampleSpringBootSSMP0.0.1-SNAPSHOTSpringBootSSMPSpringBootSSMP17org.springframework.bootspring-boot-starter-webcom.baomidoumybatis-plus-boot-starter3.4.3com.alibabadruid-spring-boot-starter1.2.6mysqlmysql-connector-javaruntimeorg.projectlomboklombokorg.springframework.bootspring-boot-starter-testtestorg.springframework.bootspring-boot-maven-plugin

创建数据库

-- ----------------------------
-- Table structure for tbl_book
-- ----------------------------
DROP TABLE IF EXISTS `tbl_book`;
CREATE TABLE `tbl_book`  (`id` int(11) NOT NULL AUTO_INCREMENT,`type` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,`name` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,`description` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 51 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;-- ----------------------------
-- Records of tbl_book
-- ----------------------------
INSERT INTO `tbl_book` VALUES (1, '计算机理论', 'Spring实战 第5版', 'Spring入门经典教程，深入理解Spring原理技术内幕');
INSERT INTO `tbl_book` VALUES (2, '计算机理论', 'Spring 5核心原理与30个类手写实战', '十年沉淀之作，手写Spring精华思想');
INSERT INTO `tbl_book` VALUES (3, '计算机理论', 'Spring 5 设计模式', '深入Spring源码剖析Spring源码中蕴含的10大设计模式');
INSERT INTO `tbl_book` VALUES (4, '计算机理论', 'Spring MVC+MyBatis开发从入门到项目实战', '全方位解析面向Web应用的轻量级框架，带你成为Spring MVC开发高手');
INSERT INTO `tbl_book` VALUES (5, '计算机理论', '轻量级Java Web企业应用实战', '源码级剖析Spring框架，适合已掌握Java基础的读者');
INSERT INTO `tbl_book` VALUES (6, '计算机理论', 'Java核心技术 卷I 基础知识（原书第11版）', 'Core Java 第11版，Jolt大奖获奖作品，针对Java SE9、10、11全面更新');
INSERT INTO `tbl_book` VALUES (7, '计算机理论', '深入理解Java虚拟机', '5个维度全面剖析JVM，大厂面试知识点全覆盖');
INSERT INTO `tbl_book` VALUES (8, '计算机理论', 'Java编程思想（第4版）', 'Java学习必读经典,殿堂级著作！赢得了全球程序员的广泛赞誉');
INSERT INTO `tbl_book` VALUES (9, '计算机理论', '零基础学Java（全彩版）', '零基础自学编程的入门图书，由浅入深，详解Java语言的编程思想和核心技术');
INSERT INTO `tbl_book` VALUES (10, '市场营销', '直播就该这么做：主播高效沟通实战指南', '李子柒、李佳琦、薇娅成长为网红的秘密都在书中');
INSERT INTO `tbl_book` VALUES (11, '市场营销', '直播销讲实战一本通', '和秋叶一起学系列网络营销书籍');
INSERT INTO `tbl_book` VALUES (12, '市场营销', '直播带货：淘宝、天猫直播从新手到高手', '一本教你如何玩转直播的书，10堂课轻松实现带货月入3W+');

yml

server:port: 80spring:datasource:druid:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTCusername: rootpassword: 123456mybatis-plus:global-config:db-config:table-prefix: tbl_id-type: auto # 数据库id自增configuration:log-impl: org.apache.ibatis.logging.stdout.StdOutImpl # 开启MP运行日志

lonbok实体类快速开发

简介：一个提供一组注解来简化POJO实体类的开发的Java库。

导入依赖

	
org.projectlomboklombok

创建Book类

package com.example.springbootssmp.domain;
//lombokimport lombok.Data;@Data
// @Data注解实现了类的除了构造方法外的所有方法的自动生成，大大简化了开发
public class Book {private Integer id;private String type;private String name;private String description;
}

创建BookDao

package com.example.springbootssmp.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;import com.example.springbootssmp.domain.Book;
import org.apache.ibatis.annotations.Mapper;@Mapper
public interface BookDao extends BaseMapper {}

数据层开发（实现基础的CRUD)

测试dao层

测试代码
测试基本的增删改查

@SpringBootTest
public class BookDaoTestCase {@Autowiredprivate BookDao bookDao;@Testvoid testGetById(){System.out.println(bookDao.selectById(1));}@Testvoid testSave(){Book book = new Book();book.setType("测试数据123");book.setName("测试数据123");book.setDescription("测试数据123");bookDao.insert(book);}@Testvoid testUpdate(){Book book = new Book();book.setId(17);book.setType("测试数据abcdefg");book.setName("测试数据123");book.setDescription("测试数据123");bookDao.updateById(book);}@Testvoid testDelete(){bookDao.deleteById(16);}@Testvoid testGetAll(){bookDao.selectList(null);}}

分页查询

创建配置文件

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 {@Beanpublic MybatisPlusInterceptor mybatisPlusInterceptor(){MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();interceptor.addInnerInterceptor(new PaginationInnerInterceptor());return interceptor;}
}

测试代码

@Test
void testGetPage(){IPage page = new Page(2,5); // 从第二页开始查 每页最多5个记录bookDao.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());
}

运行结果

条件查询

@Testvoid testGetBy(){QueryWrapper qw = new QueryWrapper<>();// like 条件模糊查询 查询name like Spring的 %Spring%的样子的qw.like("name","Spring");System.out.println(bookDao.selectList(qw));}@Testvoid testGetBy2(){String name = "1";LambdaQueryWrapper lqw = new LambdaQueryWrapper();//if(name != null) lqw.like(Book::getName,name);lqw.like(name != null,Book::getName,name);  // 查询之前先看看name是否为空System.out.println(bookDao.selectList(lqw));}

业务层（Service）

概述：Service实现对Dao层的控制，即业务层对数据层的控制。

注意：需要注意的是，Service的方法命名的方式需要与Dao层有所区别一点，防止搞混。

基础CRUD

方式一（原始开发）
BookService.java

public interface BookService {Boolean save(Book book);Boolean update(Book book);Boolean delete(Integer id);Book getById(Integer id);List getAll();IPage getPage(int currentPage,int pageSize);
}

BookServiceImpl.java

@Service
public class BookServiceImpl implements BookService {@Autowiredprivate BookDao bookDao;@Overridepublic Boolean save(Book book) {return bookDao.insert(book) > 0;}@Overridepublic Boolean update(Book book) {return bookDao.updateById(book) > 0;}@Overridepublic Boolean delete(Integer id) {return bookDao.deleteById(id) > 0;}@Overridepublic Book getById(Integer id) {return bookDao.selectById(id);}@Overridepublic List getAll() {return bookDao.selectList(null);}@Overridepublic IPage getPage(int currentPage, int pageSize) {IPage page = new Page(currentPage,pageSize);bookDao.selectPage(page,null);return page;}
}

方式二（业务快速开发）
文件结构

IBookService.java

public interface IBookService extends IService {//添加非通用操作API接口boolean saveBook(Book book);boolean modify(Book book);boolean delete(Integer id);IPage getPage(int currentPage, int pageSize);IPage getPage(int currentPage, int pageSize, Book book);}

BookServiceImpl.java

@Service
public class BookServiceImpl extends ServiceImpl implements IBookService {@Autowiredprivate BookDao bookDao;//添加非通用操作API@Overridepublic boolean saveBook(Book book) {return bookDao.insert(book) > 0;}@Overridepublic boolean modify(Book book) {return bookDao.updateById(book) > 0;}@Overridepublic boolean delete(Integer id) {return bookDao.deleteById(id) > 0;}@Overridepublic IPage getPage(int currentPage, int pageSize) {IPage page = new Page(currentPage,pageSize);bookDao.selectPage(page,null);return page;}@Overridepublic IPage getPage(int currentPage, int pageSize, Book book) {LambdaQueryWrapper lqw = new LambdaQueryWrapper();lqw.like(Strings.isNotEmpty(book.getType()),Book::getType,book.getType());lqw.like(Strings.isNotEmpty(book.getName()),Book::getName,book.getName());lqw.like(Strings.isNotEmpty(book.getDescription()),Book::getDescription,book.getDescription());IPage page = new Page(currentPage,pageSize);bookDao.selectPage(page,lqw);return page;}
}

测试类
文件结构

BookServiceTest.java

@SpringBootTest
public class BookServiceTest {@Autowiredprivate IBookService bookService;@Testvoid testGetById(){System.out.println(bookService.getById(4));}@Testvoid testSave(){Book book = new Book();book.setType("测试数据123");book.setName("测试数据123");book.setDescription("测试数据123");bookService.save(book);}@Testvoid testUpdate(){Book book = new Book();book.setId(17);book.setType("-----------------");book.setName("测试数据123");book.setDescription("测试数据123");bookService.updateById(book);}@Testvoid testDelete(){bookService.removeById(18);}@Testvoid testGetAll(){bookService.list();}@Testvoid testGetPage(){IPage page = new Page(2,5);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());}}

运行结果

表现层（Controller）

这里的Restful风格需要参考这篇文章：restful风格快速入门
接受参数：

• 实体数据：@RequestBody
• 路径变量：@PathVariable
  
  

方式一

package com.example.springbootssmp.controller;import com.baomidou.mybatisplus.core.metadata.IPage;
import com.example.springbootssmp.domain.Book;
import com.example.springbootssmp.service.IBookService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;import java.util.List;@RestController
@RequestMapping("/books")
public class BookController {@Autowiredprivate IBookService bookService;@GetMappingpublic List getAll(){return bookService.list();}@PostMappingpublic Boolean save(@RequestBody Book book){return bookService.save(book);}@PutMappingpublic Boolean update(@RequestBody Book book){return bookService.modify(book);}@DeleteMapping("{id}")public Boolean delete(@PathVariable Integer id){return bookService.delete(id);}@GetMapping("{id}")public Book getById(@PathVariable Integer id){return bookService.getById(id);}@GetMapping("{currentPage}/{pageSize}")public IPage getPage(@PathVariable int currentPage,@PathVariable int pageSize){return bookService.getPage(currentPage,pageSize, null);}
}

方式一存在着问题，问题在于对于返回的数据，没有一个标识，使得我们知道数据是否查询成功，如果查询失败了，怎么返回失败的信息，于是我们就在方式二中进行了完善。
这些问题导致了没有没有一个统一的返回值结果，不便于前端开发的读取数据，于是在方式二中就创建了Tool类的前后端协议。

方式二
创建util包的Tool类

package com.example.springbootssmp.controller.util;import lombok.Data;@Data
public class Tool {private Boolean flag; // 查询是否成功private Object data;  // 查询获得的数据private String msg; // 返回的信息public Tool(){}public Tool(Boolean flag){this.flag = flag;}public Tool(Boolean flag,Object data){this.flag = flag;this.data = data;}public Tool(Boolean flag,String msg){this.flag = flag;this.msg = msg;}public Tool(String msg){this.flag = false;this.msg = msg;}
}

完善BookController类

@RestController
@RequestMapping("/books")
public class BookController {@Autowiredprivate IBookService bookService;@GetMappingpublic Tool getAll(){return new Tool(true, bookService.list());}@PostMappingpublic Tool save(@RequestBody Book book) throws IOException {if (book.getName().equals("123") ) throw new IOException();boolean flag = bookService.save(book);return new Tool(flag, flag ? "添加成功^_^" : "添加失败-_-!");}@PutMappingpublic Tool update(@RequestBody Book book) throws IOException {if (book.getName().equals("123") ) throw new IOException();boolean flag = bookService.modify(book);return new Tool(flag, flag ? "修改成功^_^" : "修改失败-_-!");}@DeleteMapping("{id}")public Tool delete(@PathVariable Integer id){return new Tool(bookService.delete(id));}@GetMapping("{id}")public Tool getById(@PathVariable Integer id){return new Tool(true, bookService.getById(id));}@GetMapping("{currentPage}/{pageSize}")public Tool getPage(@PathVariable int currentPage,@PathVariable int pageSize,Book book){
//        System.out.println("参数==>"+book);IPage page = bookService.getPage(currentPage, pageSize,book);//如果当前页码值大于了总页码值，那么重新执行查询操作，使用最大页码值作为当前页码值if( currentPage > page.getPages()){page = bookService.getPage((int)page.getPages(), pageSize,book);}return new Tool(true, page);}}

前后端调用(通过axios发送异步请求)

前端文件在这里下载:https://gitee.com/geek-li-hua/widgets.git

最后的运行结果
访问地址：http://localhost/pages/books.html