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
需要添加mybatis-plus
的配置文件。
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>2.7.6version>
<relativePath/>
parent>
<groupId>com.examplegroupId>
<artifactId>SpringBootSSMPartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>SpringBootSSMPname>
<description>SpringBootSSMPdescription>
<properties>
<java.version>17java.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.4.3version>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druid-spring-boot-starterartifactId>
<version>1.2.6version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<scope>runtimescope>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-testartifactId>
<scope>testscope>
dependency>
dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>
plugins>
build>
project>
-- ----------------------------
-- 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+');
server:
port: 80
spring:
datasource:
druid:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTC
username: root
password: 123456
mybatis-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
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
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
dependency>
创建Book类
package com.example.springbootssmp.domain;
//lombok
import 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<Book> {
}
@SpringBootTest
public class BookDaoTestCase {
@Autowired
private BookDao bookDao;
@Test
void testGetById(){
System.out.println(bookDao.selectById(1));
}
@Test
void 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);
}
@Test
void 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);
}
@Test
void testDelete(){
bookDao.deleteById(16);
}
@Test
void testGetAll(){
bookDao.selectList(null);
}
}
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 {
@Bean
public 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());
}
@Test
void testGetBy(){
QueryWrapper<Book> 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));
}
@Test
void testGetBy2(){
String name = "1";
LambdaQueryWrapper<Book> lqw = new LambdaQueryWrapper<Book>();
//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));
}
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。
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<Book> getAll();
IPage<Book> getPage(int currentPage,int pageSize);
}
BookServiceImpl.java
@Service
public class BookServiceImpl implements BookService {
@Autowired
private BookDao bookDao;
@Override
public Boolean save(Book book) {
return bookDao.insert(book) > 0;
}
@Override
public Boolean update(Book book) {
return bookDao.updateById(book) > 0;
}
@Override
public Boolean delete(Integer id) {
return bookDao.deleteById(id) > 0;
}
@Override
public Book getById(Integer id) {
return bookDao.selectById(id);
}
@Override
public List<Book> getAll() {
return bookDao.selectList(null);
}
@Override
public IPage<Book> getPage(int currentPage, int pageSize) {
IPage page = new Page(currentPage,pageSize);
bookDao.selectPage(page,null);
return page;
}
}
IBookService.java
public interface IBookService extends IService<Book> {
//添加非通用操作API接口
boolean saveBook(Book book);
boolean modify(Book book);
boolean delete(Integer id);
IPage<Book> getPage(int currentPage, int pageSize);
IPage<Book> getPage(int currentPage, int pageSize, Book book);
}
BookServiceImpl.java
@Service
public class BookServiceImpl extends ServiceImpl<BookDao, Book> implements IBookService {
@Autowired
private BookDao bookDao;
//添加非通用操作API
@Override
public boolean saveBook(Book book) {
return bookDao.insert(book) > 0;
}
@Override
public boolean modify(Book book) {
return bookDao.updateById(book) > 0;
}
@Override
public boolean delete(Integer id) {
return bookDao.deleteById(id) > 0;
}
@Override
public IPage<Book> getPage(int currentPage, int pageSize) {
IPage page = new Page(currentPage,pageSize);
bookDao.selectPage(page,null);
return page;
}
@Override
public IPage<Book> getPage(int currentPage, int pageSize, Book book) {
LambdaQueryWrapper<Book> lqw = new LambdaQueryWrapper<Book>();
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;
}
}
BookServiceTest.java
@SpringBootTest
public class BookServiceTest {
@Autowired
private IBookService bookService;
@Test
void testGetById(){
System.out.println(bookService.getById(4));
}
@Test
void 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);
}
@Test
void 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);
}
@Test
void testDelete(){
bookService.removeById(18);
}
@Test
void testGetAll(){
bookService.list();
}
@Test
void testGetPage(){
IPage<Book> page = new Page<Book>(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());
}
}
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:
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 {
@Autowired
private IBookService bookService;
@GetMapping
public List<Book> getAll(){
return bookService.list();
}
@PostMapping
public Boolean save(@RequestBody Book book){
return bookService.save(book);
}
@PutMapping
public 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<Book> 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。
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 {
@Autowired
private IBookService bookService;
@GetMapping
public Tool getAll(){
return new Tool(true, bookService.list());
}
@PostMapping
public 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-_-!");
}
@PutMapping
public 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<Book> 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);
}
}