本文共 11155 字，大约阅读时间需要 37 分钟。

1.新建一个模块

2.配置项目环境及首页

注意：以下程序不用@Autowired导入的原因是会一直报bean创建失败的错误，解决方法尚未找到

1、导入依赖pom.xml

   
       
    
     4.0.0
        
            
     
      org.springframework.boot
             
     
      spring-boot-starter-parent
             
     
      2.3.5.RELEASE
             
      
         
        
    
     com.loey
        
    
     springboot-04-staffmanagement
        
    
     1.0.0
        
            
     
      11
         
        
            
                 
      
       org.mybatis.spring.boot
                  
      
       mybatis-spring-boot-starter
                  
      
       2.0.0
              
             
             
                 
      
       mysql
                  
      
       mysql-connector-java
                  
              
             
           
                 
      
       org.springframework.boot
                  
      
       spring-boot-starter-thymeleaf
              
             
                 
      
       org.springframework.boot
                  
      
       spring-boot-starter-web
              
             
                 
      
       org.springframework.boot
                  
      
       spring-boot-starter-test
                  
      
       test
                  
                      
                           
        
         org.junit.vintage
                            
        
         junit-vintage-engine
                        
                   
              
         
        
            
                 
                      
       
        src/main/java
                       
                           
        
         **/*.xml
                        
                   
              
             
                 
                  
                      
       
        org.mybatis.generator
                       
       
        mybatis-generator-maven-plugin
                       
       
        1.3.6
                       
                           
                            
        
         GeneratorMapper.xml
                            
        
         true
                            
        
         true
                        
                   
                  
                      
       
        org.springframework.boot
                       
       
        spring-boot-maven-plugin
                   
              
         
    
   

2、导入实体类

public class Department {
       private Integer deptno;    private String dname;    private String loc;

public class Employee {
       private Integer empno;    private String ename;    private String job;    private Integer mgr;    private Date hiredate;    private Double sal;    private Double comm;    private Integer deptno;    private Department department;

3、编写mapper接口以及实现类

DepartmentMapper

package com.loey.mapper;import com.loey.model.Department;import org.springframework.stereotype.Repository;import javax.annotation.Resource;import java.util.*;@Repositorypublic class DepartmentMapperImpl implements DepartmentMapper {
       private static Map
   
     map = null;    static{
           map = new HashMap
    
     ();        map.put(10,new Department(10,"人事部","北京"));        map.put(30,new Department(30,"财务部","北京"));        map.put(20,new Department(20,"后勤部","北京"));    }    @Override    public int deleteByPrimaryKey(Integer deptno) {
           map.remove(deptno);        return 0;    }    @Override    public int insert(Department record) {
           Integer deptno = record.getDeptno();        map.put(deptno,record);        return 0;    }    @Override    public Department selectByPrimaryKey(Integer deptno) {
           Department department = map.get(deptno);        return department;    }    @Override    public Collection
     
       selectAllDepartment() {
           Collection
      
        departments = map.values();        return departments;    }    @Override    public int updateByPrimaryKey(Department record) {
           Integer deptno = record.getDeptno();        map.put(deptno,record);        return 0;    }}
      
     
    
   

EmployeeMapper

package com.loey.mapper;import com.loey.model.Employee;import org.springframework.stereotype.Repository;import java.util.Collection;import java.util.List;public interface EmployeeMapper {
       int deleteByPrimaryKey(Integer empno);    int insert(Employee record);    Employee selectByPrimaryKey(Integer empno);    Collection
   
     selectAllEmployees();    int updateByPrimaryKey(Employee record);}
   

@PostConstruct注解理解

@Autowired不能给静态变量注入

Java中该注解的说明：

• @PostConstruct该注解被用来修饰一个非静态的void（）方法。
• 被@PostConstruct修饰的方法会在服务器加载Servlet的时候运行，并且只会被服务器执行一次。
• PostConstruct在构造函数之后执行，init（）方法之前执行。

通常我们会是在Spring框架中使用到@PostConstruct注解 该注解的方法在整个Bean初始化中的执行顺序：

package com.loey.mapper;import com.loey.model.Department;import com.loey.model.Employee;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Repository;import javax.annotation.PostConstruct;import java.util.*;@Repositorypublic class EmployeeMapperImpl implements EmployeeMapper {
   //   @Autowired不能给静态变量注入//    @Autowired//    private DepartmentMapper departmentMapper;/*   @Autowired    private DepartmentMapper myDepartmentMapper;    @PostConstruct    public void init(){        departmentMapper = this.myDepartmentMapper;        System.out.println(departmentMapper);    }*/    private static DepartmentMapper departmentMapper = new DepartmentMapperImpl();    //模拟数据库中的数据    private static Map
   
     employees = null;    static {
           employees = new HashMap
    
     ();//创建一个员工表      employees.put(1,new Employee(1,"zhangsan","sing",2, new Date(2001 -1900,10 - 1,8),100000.0,10.0,10,departmentMapper.selectByPrimaryKey(10)));        employees.put(2,new Employee(2,"lisi","dance",3,new Date(2002 - 1900,10 - 1,8),10000.0,5.0,30,departmentMapper.selectByPrimaryKey(30)));        employees.put(3,new Employee(3,"wangwu","sing",null,new Date(2003 - 1900,10 - 1,8),200000.0,10.0,20,departmentMapper.selectByPrimaryKey(20)));    }    //主键自增    private static Integer initId = 3;    @Override    public int deleteByPrimaryKey(Integer empno) {
           employees.remove(empno);        return 0;    }    @Override    public int insert(Employee record) {
           initId++;        Integer deptno = record.getDeptno();        Department department = departmentMapper.selectByPrimaryKey(deptno);        record.setDepartment(department);        record.setEmpno(initId);        employees.put(initId,record);        return 0;    }    @Override    public Employee selectByPrimaryKey(Integer empno) {
           Employee employee = employees.get(empno);        System.out.println(employee);        return employee;    }    @Override    public Collection
     
       selectAllEmployees() {
           Collection
      
        AllEmployees = employees.values();        System.out.println(AllEmployees);        return AllEmployees;    }    @Override    public int updateByPrimaryKey(Employee record) {
            Integer empno = record.getEmpno();        Integer deptno = record.getDeptno();        Department department = departmentMapper.selectByPrimaryKey(deptno);        record.setDepartment(department);        employees.put(empno,record);        return 0;    }}
      
     
    
   

4、编写service接口以及实现类

DepartmentService

package com.loey.service;import com.loey.model.Department;import java.util.Collection;import java.util.List;public interface DepartmentService {
       int deleteByPrimaryKey(Integer deptno);    int insert(Department record);    Department selectByPrimaryKey(Integer deptno);    Collection
   
     selectAllDepartment();    int updateByPrimaryKey(Department record);}
   

DepartmentServiceImpl

package com.loey.service;import com.loey.mapper.DepartmentMapper;import com.loey.mapper.DepartmentMapperImpl;import com.loey.model.Department;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.Collection;import java.util.List;/** * @ClassName DepartmentServiceImpl * @Author loey * @Date Create in 2021/1/1 17:47 * @Version 1.0 **/@Servicepublic class DepartmentServiceImpl implements DepartmentService{
   //    @Autowired//    private DepartmentMapper departmentMapper;    private DepartmentMapper departmentMapper = new DepartmentMapperImpl();    @Override    public int deleteByPrimaryKey(Integer deptno) {
           return departmentMapper.deleteByPrimaryKey(deptno);    }    @Override    public int insert(Department record) {
           return departmentMapper.insert(record);    }    @Override    public Department selectByPrimaryKey(Integer deptno) {
           return departmentMapper.selectByPrimaryKey(deptno);    }    @Override    public Collection
   
     selectAllDepartment() {
           return departmentMapper.selectAllDepartment();    }    @Override    public int updateByPrimaryKey(Department record) {
           return departmentMapper.updateByPrimaryKey(record);    }}
   

EmployeeService

package com.loey.service;import com.loey.model.Employee;import java.util.Collection;import java.util.List;public interface EmployeeService {
       int deleteByPrimaryKey(Integer empno);    int insert(Employee record);    Employee selectByPrimaryKey(Integer empno);    Collection
   
     selectAllEmployees();    int updateByPrimaryKey(Employee record);}
   

EmployeeServiceImpl

package com.loey.service;import com.loey.mapper.EmployeeMapper;import com.loey.mapper.EmployeeMapperImpl;import com.loey.model.Employee;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.Collection;import java.util.List;@Servicepublic class EmployeeServiceImpl implements EmployeeService {
   //    @Autowired//    private EmployeeMapper employeeMapper;    private EmployeeMapper employeeMapper = new EmployeeMapperImpl();    @Override    public int deleteByPrimaryKey(Integer empno) {
           return employeeMapper.deleteByPrimaryKey(empno);    }    @Override    public int insert(Employee record) {
           return employeeMapper.insert(record);    }    @Override    public Employee selectByPrimaryKey(Integer empno) {
           return employeeMapper.selectByPrimaryKey(empno);    }    @Override    public Collection
   
     selectAllEmployees() {
           System.out.println(employeeMapper);        return employeeMapper.selectAllEmployees();    }    @Override    public int updateByPrimaryKey(Employee record) {
           return employeeMapper.updateByPrimaryKey(record);    }}
   

5、注意Maven资源导出问题！

           
                
                     
      
       src/main/java
                      
                          
       
        **/*.xml
                       
                  
             
        
   

6.application.properties

#设置连接数据库的配置spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driverspring.datasource.url=jdbc:mysql://localhost:3306/staff_management?useUnicode=true&characterEncoding=UTF-8&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=GMT%2B8spring.datasource.username=rootspring.datasource.password=1127

即使没有连接数据库也要写不然运行不了

3.导入静态资源

1、css，js等放在static文件夹下

4.最终结构如下：

转载地址：http://vmuki.baihongyu.com/