先导入所需的html资源，html页面保存到templates文件夹中，其余的css，img，js导入到静态资源文件夹中。
1.首页的实现
直接调用会丢失首页的css格式，需要进行thymeleaf接管，并且改掉引用的格式
使用thymeleaf语句之前先导入文件头
xmlns:th="http://www.thymeleaf.org
链接使用@{}，文本使用#{}
2.模拟数据库的实现
创建实体类pojo
部门类：
package com.jie.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Department {
private Integer id;
private String departmentName;
}
员工类：
package com.jie.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.util.Date;
@Data
@NoArgsConstructor
public class Employee {
private Integer id;
private String lastName;
private String email;
private Integer gender;
private Department department;
private Date birth;
//将日期改为自动创建
public Employee(Integer id, String lastName, String email, Integer gender, Department department) {
this.id = id;
this.lastName = lastName;
this.email = email;
this.gender = gender;
this.department = department;
this.birth = new Date();
}
}
编写dao层
package com.jie.dao;
import com.jie.pojo.Department;
import org.springframework.stereotype.Repository;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
@Repository
public class DepartmentDao {
private static Map departments = null;
static {
departments = new HashMap();
departments.put(101,new Department(101,"教学部"));
departments.put(102,new Department(102,"市场部"));
departments.put(103,new Department(103,"教研部"));
departments.put(104,new Department(104,"运营部"));
departments.put(105,new Department(105,"后勤部"));
}
public Collection getDepartments(){
return departments.values();
}
public Department getDepartmentById(Integer id){
return departments.get(id);
}
}
package com.jie.dao;
import com.jie.pojo.Department;
import com.jie.pojo.Employee;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
@Repository
public class EmployeeDao {
private static Map employees = null;
@Autowired
private DepartmentDao departmentDao;
static {
employees = new HashMap();
employees.put(1001,new Employee(1001,"AA","A4536251@qq.com",1,new Department(101,"教学部")));
employees.put(1002,new Employee(1002,"BB","B4536251@qq.com",0,new Department(102,"市场部")));
employees.put(1003,new Employee(1003,"CC","C4536251@qq.com",1,new Department(103,"教研部")));
employees.put(1004,new Employee(1004,"DD","D4536251@qq.com",0,new Department(104,"运营部")));
employees.put(1005,new Employee(1005,"EE","E4536251@qq.com",1,new Department(105,"后勤部")));
}
//增加员工 的实现
private static Integer initId = 1006;
public void Save(Employee employee){
if (employee.getId()==null){
employee.setId(initId++);
}
employee.setDepartment(departmentDao.getDepartmentById(employee.getDepartment().getId()));
employees.put(employee.getId(),employee);
}
//查询全部的员工
public Collection getAll(){
return employees.values();
}
//通过id查询员工
public Employee getEmployeeById(Integer id){
return employees.get(id);
}
//通过id删除员工
public void delete(Integer id){
employees.remove(id);
}
}
这样就模拟好了数据库的实现，还有增删改查Template。
连接数据库：
基础配置：
application.yaml
spring:
datasource:
username: root
password: 123456
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT
package com.gao;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import javax.sql.DataSource;
@SpringBootTest
class Spring03DataApplicationTests {
@Autowired
DataSource dataSource;
@Test
void contextLoads() {
System.out.println(dataSource.getClass());
}
}
JdbcTemplate主要提供以下几类方法：
-
execute方法：可以用于执行任何SQL语句，一般用于执行DDL语句；
-
update方法及batchUpdate方法：update方法用于执行新增、修改、删除等语句；batchUpdate方法用于执行批处理相关语句；
-
query方法及queryForXXX方法：用于执行查询相关语句；
-
call方法：用于执行存储过程、函数相关语句。
package com.gao.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
import java.util.Map;
@RestController
public class JDBCController {
@Autowired
JdbcTemplate jdbcTemplate;
@GetMapping("/list")
public List> userLIst(){
String sql = "select * from user";
List> list_maps = jdbcTemplate.queryForList(sql);
return list_maps;
}
@GetMapping("/addUser")
public String addUser(){
String sql = "insert into user(id,name,pwd) values (5,'就这',456678)";
jdbcTemplate.update(sql);
return "成功";
}
@GetMapping("/updateUser/{id}")
public String updateUser(@PathVariable("id") int id){
String sql = "update user set name=?,pwd=? where id =" +id;
Object[] object = new Object[2];
object[0] = "杰杰";
object[1] = 435567;
jdbcTemplate.update(sql,object);
return "ok";
}
@GetMapping("/deleteUser/{id}")
public String deleteUser(@PathVariable("id") int id){
String sql = "delete from user where id=?";
jdbcTemplate.update(sql,id);
return "delete ok";
}
}
