初学SpringBoot和SpringBoot整合SSMP
SpringBoot基础学习笔记
创建SpringBoot工程
略
Application类(引导类)
package com.judy;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class FristSpringBootApplication {
/**
SpringBoot的引导类是Boot工程的执行入口，运行main方法就可以启动项目
SpringBoot工程运行后初始化Spring容器，扫描引导类所在包加载bean
*/
public static void main(String[] args) {
SpringApplication.run(FristSpringBootApplication.class, args);
}
}
pom.xml文件
通过勾选添加maven坐标
<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>2.7.1version>
<relativePath/>
parent>
<groupId>com.judygroupId>
<artifactId>Frist_SpringBootartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>Frist_SpringBootname>
<description>Frist_SpringBootdescription>
<properties>
<java.version>1.8java.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.mybatis.spring.bootgroupId>
<artifactId>mybatis-spring-boot-starterartifactId>
<version>2.2.2version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<scope>runtimescope>
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>
yml文件(properties文件)
# 修改服务器端口
server:
port: 80
# 修改banner
spring:
banner:
location: classpath:banner.txt
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTC
username: root
password: root
# 数据库相关配置
整合第三方技术
JUnit
- 导入测试对应的starter
- 测试类使用@SpringBootTest修饰
- 使用自动装配的形式添加要测试的对象
注意：
- 测试类如果存在于引导类所在包或子包中无需指定引导类
- 测试类如果不存在于引导类所在的包或子包中需要通过classes
属性指定引导类
@SpringBootTest(classes = SpringbootJUnitApplication.class)//测试类注解
class Springboot07JunitApplicationTests {
@Autowired
private Service service;
@Test
public void testSave(){
service.save();
}
}
MyBatis
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/dataBase?serverTimezone=UTC
username: root
password: root
@Mapper
public interface UserDao {
@Select("select * from user")
public List<User> getAll();
}
@SpringBootTest
class SpringbootMybatisApplicationTests {
@Autowired
private Dao dao;
@Test
public void testGetById() {
User user = dao.getById(1);
System.out.println(user);
}
}
MyBatis-Plus
手动添加SpringBoot整合MyBatis-Plus的坐标，可以通过mvnrepository获取
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.4.3version>
由于SpringBoot中未收录MyBatis-Plus的坐标版本，需要指定对应的Version
dependency>
//定义数据层接口与映射配置，继承BaseMapper
@Mapper
public interface UserDao extends BaseMapper<User> {
}
Druid
# 变更Druid的配置方式
spring:
datasource:
druid:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/dataBase?serverTimezone=UTC
username: root
password: root
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druid-spring-boot-starterartifactId>
<version>1.2.6version>
dependency>
SpringBoot整合SSMP(Spring+SpringMVC+MyBatisPlus)
LomBok：一个Java类库，提供了一组注解，简化POJO实体类开发
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
dependency>
实体类开发：
//@Data (LomBok)
@Data/*作用：为当前实体类在编译期设置对应的get/set方法，
toString方法，hashCode方法，equals方法等*/
public class Book {
private Integer id;
private String type;
private String name;
private String description;
}
数据层开发：
- 导入MyBatisPlus与Druid对应的starter
springboot没有对应版本:( 要自行添加
<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>
- 配置数据源与MyBatisPlus对应的基础配置
spring:
datasource:
druid:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/ssm_db?servierTimezone=UTC
username: root
password: root
mybatis-plus:
global-config:
db-config:
table-prefix: tbl_ #数据库对应名称前缀
id-type: auto # 主键
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl # 开启日志
开发Dao接口
@Mapper
//继承BaseMapper并指定泛型
//（MyBatisPlus）Mapper 继承该接口后，无需编写 mapper.xml 文件，即可获得CRUD功能
public interface BookDao extends BaseMapper<Book> {
}
分页功能：
- 使用IPage封装分页数据
- 分页操作依赖MyBatisPlus分页拦截器实现功能
- 借助MyBatisPlus日志查阅执行SQL语句
IPage对象中封装了分页操作中的所有数据
数据
当前页码值
每页数据总量
最大页码值
数据总量
分页操作是在MyBatisPlus的常规操作基础上增强得到，内部是动态的拼写SQL语句，因此需要增强对应的功能，使用MyBatisPlus拦截器实现
@Configuration
public class MpConfig {
@Bean
public MybatisPlusInterceptor mpInterceptor() {
//1.定义Mp拦截器
MybatisPlusInterceptor mpInterceptor = new MybatisPlusInterceptor();
//2.添加具体的拦截器
//分页功能拦截器
mpInterceptor.addInnerInterceptor(new PaginationInnerInterceptor());
return mpInterceptor;
}
}
业务层开发：
//定义接口
public interface BookService {
boolean save(Book book);
boolean delete(Integer id);
boolean update(Book book);
Book getById(Integer id);
List<Book> getAll();
IPage<Book> getByPage(int currentPage,int pageSize);
}
//实现类
@Service
public class BookServiceImpl implements BookService {
@Autowired
private BookDao bookDao;
//bookDao已经继承BaseDao接口
//内部定义了相关方法
@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);
return bookDao.selectPage(page,null);
}
}
表现层开发：
表现层消息一致性处理
/*
1. 设计统一的返回值结果类型便于前端开发读取数据
2. 返回值结果类型可以根据需求自行设定，没有固定格式
3. 返回值结果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
public class R {
private Boolean flag;
private Object data;
private String msg;
public R() {
}
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;
}
}
业务消息一致性处理
//作为springMVC的异常处理器
@RestControllerAdvice
public class ProjectExceptionAdvice {
//拦截所有的异常信息
@ExceptionHandler
public R doException(Exception ex){
ex.printStackTrace();
return new R(false,"出错了");
}
}
/**
基于Restful进行表现层接口开发
新增：POST
删除：DELETE
修改：PUT
查询：GET
*/
@RestController
@RequestMapping("/books")
public class BookController {
@Autowired
private BookService bookService;
@GetMapping
public R getAll(){
return new R(true,bookService.getAll());
}
@PostMapping
public R save(@RequestBody Book book){
return new R(bookService.save(book));
}
@PutMapping
public R update(@RequestBody Book book){
return new R(bookService.update(book));
}
@DeleteMapping("{id}")
public R delete(@PathVariable Integer id){
return new R(bookService.delete(id));
}
@GetMapping("{id}")
public R getById(@PathVariable Integer id){
return new R(true,bookService.getById(id));
}
@GetMapping("{current}/{size}")
public R getPage(@PathVariable int current,@PathVariable int size){
IPage<Book> page = bookService.getPage(current, size);
//如果当前页码大于最大页码。则重新执行查询and当前页码值为最大页码数
if(current > page.getPages()){
page = bookService.getPage((int)page.getPages(), size);
}
return new R(true,page);
}
}
目录：
- pom.xml
配置起步依赖
<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>2.7.0version>
parent>
<groupId>com.judygroupId>
<artifactId>SpringBoot_SSMP_demoartifactId>
<version>0.0.1-SNAPSHOTversion>
<properties>
<java.version>1.8java.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
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.springframework.bootgroupId>
<artifactId>spring-boot-starter-testartifactId>
<scope>testscope>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-devtoolsartifactId>
dependency>
dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
<version>2.7.0version>
plugin>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-surefire-pluginartifactId>
<configuration>
<testFailureIgnore>truetestFailureIgnore>
configuration>
plugin>
plugins>
build>
project>
- application.yml
设置数据源、端口、框架技术相关配置等
server:
port: 80
spring:
datasource:
druid:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/ssm_db?serverTimezone=UTC
username: root
password: 123123
mybatis-plus:
global-config:
db-config:
table-prefix: tbl_
id-type: auto
# 主键
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
# 开启日志
- dao
继承BaseMapper、设置@Mapper
package com.judy.dao;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.judy.domain.Book;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
/**
* @author:Judy
* ClassName:BookDao
* package:com.judy.dao
*/
@Mapper
public interface BookDao extends BaseMapper<Book> {
}
- service
调用数据层接口或MyBatis-Plus提供的接口快速开发
package com.judy.service;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.judy.domain.Book;
import java.util.List;
/**
* @author:Judy
* ClassName:BookService
* package:com.judy.service
*/
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);
IPage<Book> getPage(int currentPage,int pageSize,Book book);
}
package com.judy.service.Impl;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.judy.dao.BookDao;
import com.judy.domain.Book;
import com.judy.service.BookService;
import org.apache.logging.log4j.util.Strings;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
/**
* @author:Judy
* @date:2022/6/19 15:40
* ClassName:BookServiceImpl
* package:com.judy.service.Impl
*/
@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);
return bookDao.selectPage(page,null);
}
}
- controller
基于Restful开发
package com.judy.controller;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.judy.controller.utils.R;
import com.judy.domain.Book;
import com.judy.service.BookService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
/**
* @author:Judy
* ClassName:BookController
* package:com.judy.controller
*/
@RestController
@RequestMapping("/books")
public class BookControllerR {
@Autowired
private BookService bookService;
@GetMapping
public R getAll(){
return new R(true,bookService.getAll());
}
@PostMapping
public R save(@RequestBody Book book){
return new R(bookService.save(book));
}
@PutMapping
public R update(@RequestBody Book book){
return new R(bookService.update(book));
}
@DeleteMapping("{id}")
public R delete(@PathVariable Integer id){
return new R(bookService.delete(id));
}
@GetMapping("{id}")
public R getById(@PathVariable Integer id){
return new R(true,bookService.getById(id));
}
@GetMapping("{current}/{size}")
public R getPage(@PathVariable int current,@PathVariable int size){
IPage<Book> page = bookService.getPage(current, size);
//如果当前页码大于最大页码。则重新执行查询and当前页码值为最大页码数
if(current > page.getPages()){
page = bookService.getPage((int)page.getPages(), size);
}
return new R(true,page);
}
}
- 其他：
package com.judy.controller.utils;
import lombok.Data;
/**
* @author:Judy
* ClassName:R
* package:com.judy.controller.utils
*/
@Data
public class R {
private Boolean flag;
private Object data;
private String msg;
public R() {
}
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;
}
}
package com.judy.controller.utils;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
/**
* @author:Judy
* ClassName:ProjectExceptionAdvice
* package:com.judy.controller.utils
*/
//作为springMVC的异常处理器
@RestControllerAdvice
public class ProjectExceptionAdvice {
//拦截所有的异常信息
@ExceptionHandler
public R doException(Exception ex){
//
ex.printStackTrace();
return new R(false,"BOOMMMM!!!!");
}
}
package com.judy.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;
/**
* @author:Judy
* ClassName:MPconfig
* package:com.judy.config
*/
@Configuration//配置类
public class MPconfig {
@Bean//第三方Bean交给spring管理
public MybatisPlusInterceptor mybatisPlusInterceptor(){
MybatisPlusInterceptor mybatisPlusInterceptor = new MybatisPlusInterceptor();
mybatisPlusInterceptor.addInnerInterceptor(new PaginationInnerInterceptor());
//分页功能拦截器
return mybatisPlusInterceptor;
}
}