搭建springboot 步骤（查询所有员工为例）

1.新建项目 选择JDBC API / Mybatis Framework /MySQL Driver/Spring Boot Dev Tools /Spring Web/Thymeleaf
2.导入文件application.properties

server.port=8888
server.servlet.context-path=/exec200330

spring.datasource.name=ds
spring.datasource.url=jdbc:mysql://localhost:3306/project2?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT%2B8
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.type=org.apache.commons.dbcp.BasicDataSource
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

mybatis.mapper-locations=classpath:mapper/*.xml

spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html
spring.thymeleaf.mode=html
spring.thymeleaf.encoding=utf-8
spring.thymeleaf.cache=false
spring.resources.chain.strategy.content.enabled=true
spring.resources.chain.strategy.content.paths=/**

spring.servlet.multipart.max-file-size=10MB
spring.servlet.multipart.max-request-size=20MB
在这里插入代码片

3.导入pom.xml文件。

	4.0.0
	
		org.springframework.boot
		spring-boot-starter-parent
		2.2.5.RELEASE
		 
	
	com.neuedu
	exec200330
	0.0.1-SNAPSHOT
	exec200330
	Demo project for Spring Boot

	
		1.8
	

	
		
			org.springframework.boot
			spring-boot-starter-jdbc
			
				
				
					org.apache.tomcat
					tomcat-jdbc
				
			
		
		
			org.springframework.boot
			spring-boot-starter-thymeleaf
		
		
			org.springframework.boot
			spring-boot-starter-web
		
		
			org.mybatis.spring.boot
			mybatis-spring-boot-starter
			2.1.2
		

		
			org.springframework.boot
			spring-boot-devtools
			runtime
			true
		
		
			mysql
			mysql-connector-java
			runtime
		
		
			commons-dbcp
			commons-dbcp
			1.4
		
		
			org.springframework.boot
			spring-boot-starter-test
			test
			
				
					org.junit.vintage
					junit-vintage-engine
				
			
		
	

	
		
			
				org.springframework.boot
				spring-boot-maven-plugin
			
		
	

4.拷贝EmployeeMapper.xml文件

    
       
       
       
       
         
         
         
       
    
    
    
    
    
        SELECT e.*,d.dname
        FROM employees e 
        LEFT JOIN dept d 
        ON (e.deptid = d.deptid)
    
    
    
	

5.把要想写的对象，进行封装新建com.neuedu.po 包 新建EmployeePO.java类

package com.neuedu.po;

import java.sql.Date;

public class EmployeePO {
	
	private Integer empid;
	private String ename;
	private Date hiredate;
	private DeptPO dept;
	
	public Integer getEmpid() {
		return empid;
	}
	public void setEmpid(Integer empid) {
		this.empid = empid;
	}
	public String getEname() {
		return ename;
	}
	public void setEname(String ename) {
		this.ename = ename;
	}
	public Date getHiredate() {
		return hiredate;
	}
	public void setHiredate(Date hiredate) {
		this.hiredate = hiredate;
	}
	public DeptPO getDept() {
		return dept;
	}
	public void setDept(DeptPO dept) {
		this.dept = dept;
	}

}

6.新建com.neuedu.mapper包 新建 EmployeeMapper.java 类

package com.neuedu.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Mapper;

import com.neuedu.po.EmployeePO;


@Mapper
public interface EmployeeMapper {
	
	
	public List getEmployeeList();

}

7.新建com.neuedu.service包 新建EmployeeService.java类

package com.neuedu.service;

import java.util.List;

import com.neuedu.po.EmployeePO;

public interface EmployeeService {
	
	public List getEmployeeList();

}

8.新建com.neuedu.service.impl 包 新建 EmployeeServiceImpl.java类

package com.neuedu.service.impl;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.neuedu.mapper.EmployeeMapper;
import com.neuedu.po.EmployeePO;
import com.neuedu.service.EmployeeService;

@Service
public class EmployeeServiceImpl implements EmployeeService{
	
	
	@Autowired
	private EmployeeMapper mapper;

	@Override
	public List getEmployeeList() {
		// TODO Auto-generated method stub
		return mapper.getEmployeeList();
	}

}

9.新建com.neuedu.controller 包 新建EmployeeHandler.java类

package com.neuedu.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.neuedu.po.EmployeePO;
import com.neuedu.service.EmployeeService;

@RestController
public class EmployeeHandler {
	
	
	@Autowired
	private EmployeeService es;
	@RequestMapping("/emp/list")
	public List getEmployeeList(){
		return es.getEmployeeList();
		
	}

}

10.最后打开spring boot APP 测试程序