实体类package com.example.pojo;
public class User {
private String name;
private int age;
private String address;
}数据访问层接口package com.example.dao;
import com.example.pojo.User;
/
*** 数据访问层接口
*/
public interface UserMapper {
//导入用户信息
int insertUser(User user);
}实现类package com.example.dao;
import com.example.pojo.User;
/
*** 数据访问层的实现类
*/
public class UserMapperImpl implements UserMapper{
//模拟用户信息导入
@Override
public int insertUser(User user) {
System.out.println("用户: " + user.getName() + ", 导入成功!");
return 1;
}
}业务逻辑层接口package com.example.Service;
import com.example.pojo.User;
/
*** 业务逻辑层接口
*/
public interface UserService {
//导入用户数据的功能
int insertUser(User user);
}实现类package com.example.Service.impl;
import com.example.Service.UserService;
import com.example.dao.UserMapper;
import com.example.dao.UserMapperImpl;
import com.example.pojo.User;
/
*** 业务逻辑层实现类
*/
public class UserServiceImpl implements UserService {
//数据访问层接口指向数据访问层实现类
UserMapper userMapper = new UserMapperImpl();
@Override
public int insertUser(User user) {
return userMapper.insertUser(user);
}
}界面层package com.example.controller;
import com.example.Service.UserService;
import com.example.Service.impl.UserServiceImpl;
import com.example.pojo.User;
/
*** 界面层
*/
public class UserController {
//业务逻辑层接口指向业务逻辑层实现类
UserService userService = new UserServiceImpl();
public int insertUser(User user){
return userService.insertUser(user);
}
}测试package com.example.test;
import com.example.controller.UserController;
import com.example.pojo.User;
import org.junit.Test;
public class TestInsert {
//测试非Spring框架的简单三层架构
@Test
public void testInsertUser(){
UserController userController = new UserController();
int num = userController.insertUser(new User("荷包蛋", 20, "黑河"));
if(num == 1){
System.out.println("非Spring框架的简单三层架构,运行成功!");
}else{
System.out.println("非Spring框架的站群服务器简单三层架构,运行失败!");
}
}
}输出结果用户: 荷包蛋, 导入成功!
Spring接管下的简单三层架构,运行成功!
Process finished with exit code 0测试分析测试执行流程示意图
测试分析层级变化：界面层 --> 业务逻辑层 --> 数据访问层 --> 业务逻辑层 --> 界面层对象访问的变化：界面层对象 --> 业务逻辑层接口指向业务逻辑层实现类 --> 数据访问层接口指向数据访问层实现类 --> 数据访问层实现类完成对数据的操作方法调用变化：界面层对象的insertUser(User u) --> 业务逻辑层实现类的insertUser(User u) --> 数据访问层实现类的insertUser(User u)
Spring接管下的三层项目构建对传统三层项目构建的修改：由上述测试分析中"对象访问的变化可知"，需要用到的构学实现类有：UserController，UserServiceImpl，层项UserMapperImpl在Spring接管下，IT技术网目架需要在bean工厂中，构学注册上述实体类的层项对象，将原先需要程序员手动创建管理的目架对象交给Spring框架去接手管理
业务逻辑层实现类修改为：
//此时的业务逻辑层实现类：不再手动创建数据访问层的对象，交给Spring容器来管理，构学新增：setter方法和无参构造函数
package com.example.Service.impl;
import com.example.Service.UserService;
import com.example.dao.UserMapper;
import com.example.pojo.User;
/
*** 业务逻辑层实现类
*/
public class UserServiceImpl implements UserService {
//数据访问层接口指向数据访问层实现类
public UserMapper userMapper;
public void setUserMapper(UserMapper userMapper) {
this.userMapper = userMapper;
}
public UserServiceImpl() {
}
@Override
public int insertUser(User user) {
return userMapper.insertUser(user);
}
}界面层所做修改与对业务逻辑层的层项实现类的修改类似：package com.example.controller;
import com.example.Service.UserService;
import com.example.pojo.User;
/
*** 界面层
*/
public class UserController {
//业务逻辑层接口指向业务逻辑层实现类
UserService userService;
public void setUserService(UserService userService) {
this.userService = userService;
}
public UserController() {
}
public int insertUser(User user){
return userService.insertUser(user);
}
}applicationContext.xml
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
测试package com.example.test;
import com.example.controller.UserController;
import com.example.pojo.User;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestInsert {
//测试Spring接管下的简单三层架构
@Test
public void testInsertUser(){
//创建Spring容器
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
//取出界面层对象
UserController uController = (UserController) applicationContext.getBean("uController");
//调用界面层对象方法
int num = uController.insertUser(new User("荷包蛋", 20, "黑河"));
if(num == 1){
System.out.println("Spring接管下的简单三层架构,运行成功!");
}else{
System.out.println("Spring接管下的简单三层架构,运行失败!");
}
}
}输出结果用户: 荷包蛋, 导入成功!
Spring接管下的WordPress模板简单三层架构,运行成功!
Process finished with exit code 0(责任编辑：应用开发)
