Web后端开发中对三层架构解耦之控制反转与依赖注入

package com.bigdate.threetier_architecture.dao.impl;
 
import com.bigdate.threetier_architecture.dao.EmpDao;
import com.bigdate.threetier_architecture.pojo.Emp;
import com.bigdate.threetier_architecture.util.XmlParserUtils;
import org.springframework.stereotype.Component;
 
import java.util.List;
 
//交给ioc容器处理 控制反转 称为ioc容器中的bean
@Component
public class EmpDaoA implements EmpDao {
    @Override
    public List<Emp> listEmp() {
        String file=this.getClass().getClassLoader().getResource("emp.xml").getFile();
        List<Emp>empList= XmlParserUtils.parse(file,Emp.class);
        return empList;
    }
}

package com.bigdate.threetier_architecture.service.impl;
 
import com.bigdate.threetier_architecture.dao.EmpDao;
import com.bigdate.threetier_architecture.dao.impl.EmpDaoA;
import com.bigdate.threetier_architecture.pojo.Emp;
import com.bigdate.threetier_architecture.service.EmpService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
 
import java.util.List;
 
//交给ioc容器处理 控制反转 称为ioc容器中的bean
@Component
public class EmpServiceA implements EmpService {
 
    @Autowired//程序在运行时 ioc会提供该类型的bean对象 并赋值给该对象 依赖注入
    private EmpDao empDao;
    @Override
    public List<Emp> listEmp() {
        List<Emp> empList=empDao.listEmp();
        empList.stream().forEach(emp -> {
 
            //处理gender
            String gender=emp.getGender();
            if(gender.equals("1")){
                emp.setGender("男");
            }else emp.setGender("女");
 
            //处理job
            String job=emp.getJob();
            if(job.equals("1")){
                emp.setJob("学生");
            }else emp.setJob("老师");
 
 
 
        });
        return empList;
    }
}

package com.bigdate.threetier_architecture.controller;
 
import com.bigdate.threetier_architecture.pojo.Emp;
import com.bigdate.threetier_architecture.pojo.Result;
import com.bigdate.threetier_architecture.service.EmpService;
import com.bigdate.threetier_architecture.service.impl.EmpServiceA;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
 
import java.util.List;
 
@RestController
public class Controller {
    @Autowired//程序在运行时 ioc会提供该类型的bean对象 并赋值给该对象 依赖注入
    private EmpService empService;
 
    @RequestMapping("/listEmp")
    public Result list(){
 
        //调用service响应数据 再响应数据
        List<Emp> empList=empService.listEmp();
 
        //响应数据
        return Result.success(empList);
 
    }
}