springboot整合SSM实现简易的CRUD操作

项目图示：

在这里插入图片描述

一、导入响应的pom依赖

<?xml version="1.0" encoding="UTF-8"?>
<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>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
       

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.31</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.18</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

二、编译配置文件

application.properties

spring.thymeleaf.cache=false
spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html

application.yml

server:
  port: 8888

mybatis:
  config-location: classpath:mybatis/mybatis-config.xml        # mybatis配置文件所在路径
  type-aliases-package: com.entities                          # 所有Entity别名类所在包
  mapper-locations:
    - classpath:mybatis/mapper/**/*.xml                       # mapper映射文件

spring:
  application:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource            # 当前数据源操作类型
    driver-class-name: com.mysql.cj.jdbc.Driver           # mysql驱动包
    url: jdbc:mysql://localhost:3306/cloud?serverTimezone=UTC              # 数据库名称
    username: root
    password: 123456
    dbcp2:
      min-idle: 5                                           # 数据库连接池的最小维持连接数
      initial-size: 5                                       # 初始化连接数
      max-total: 5                                          # 最大连接数
      max-wait-millis: 200                                  # 等待连接获取的最大超时时间

三、按图所示，编写对应的实体类

在这里插入图片描述
1.Controller

package com.Controller;

import java.util.List;

import com.Service.DeptService;
import com.entities.Dept;
import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class DeptController
{
    
    
	@Autowired
	private DeptService service;
	
	@RequestMapping(value = "/dept/add", method = RequestMethod.POST)
	public boolean add(@RequestBody Dept dept)
	{
    
    
		return service.add(dept);
	}

	@RequestMapping(value = "/dept/get/{id}", method = RequestMethod.GET)
	public Dept get(@PathVariable("id") Long id)
	{
    
    
		return service.get(id);
	}

	@RequestMapping(value = "/dept/list", method = RequestMethod.GET)
	public List<Dept> list()
	{
    
    
		return service.list();
	}
	
}

2.Dao

package com.Dao;
import java.util.List;
import com.entities.Dept;
import org.apache.ibatis.annotations.Mapper;
@Mapper
public interface DeptDao
{
    
    
	public boolean addDept(Dept dept);

	public Dept findById(Long id);

	public List<Dept> findAll();
}

3.entities（因为这里使用的是lombok自动生成getter和setter方法方便操作）

package com.entities;

import java.io.Serializable;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;
import lombok.experimental.Accessors;

@SuppressWarnings("serial")
@NoArgsConstructor
@AllArgsConstructor
@Data
@Accessors(chain=true)
public class Dept implements Serializable// entity --orm--- db_table
{
    
    
	private Long 	deptno; // 主键
	private String 	dname; // 部门名称
	private String 	db_source;//源

}

4.Service
接口方法

package com.Service;

import com.entities.Dept;

import java.util.List;



public interface DeptService
{
    
    
	public boolean add(Dept dept);

	public Dept get(Long id);

	public List<Dept> list();
}

实现类方法

package com.Service.impl;

import java.util.List;

import com.Dao.DeptDao;
import com.Service.DeptService;
import com.entities.Dept;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;


@Service
public class DeptServiceImpl implements DeptService
{
    
    
	@Autowired
	private DeptDao dao;
	
	@Override
	public boolean add(Dept dept)
	{
    
    
		return dao.addDept(dept);
	}

	@Override
	public Dept get(Long id)
	{
    
    
		return dao.findById(id);
	}

	@Override
	public List<Dept> list()
	{
    
    
		return dao.findAll();
	}

}

四、source包(mybatis/mapper)

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.Dao.DeptDao">

	<select id="findById" resultType="Dept" parameterType="Long">
		select deptno,dname,db_source from dept where deptno=#{deptno};
	</select>
	<select id="findAll" resultType="Dept">
		select deptno,dname,db_source from dept;
	</select>
	<insert id="addDept" parameterType="Dept">
		INSERT INTO dept(dname,db_source) VALUES(#{dname},DATABASE());
	</insert>

</mapper>

mybatis开启二级缓存

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
  PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>

	<settings>
		<setting name="cacheEnabled" value="true" /><!-- 二级缓存开启 -->
	</settings>

</configuration>