创建项目
1、创建maven / SpringBoot 项目
2、添加依赖
3、创建SpringBoot引导类 Application
项目基本结构
引导类Application 同级目录下创建模块包
在resources目录存放xml、配置文件及页面等
controller 控制层
定义前端请求与后端接口间的映射关系
Tips:这里只是映射,具体的业务逻辑方法在services包中说明
工作原理:
- 前端向指定的URL发送请求;
- 后端接收到请求,根据URL的格式,查找controller层中的不同方法,将该请求传给符合条件的方法进行处理;
- 处理完毕后返回response(这个response可以是一个html页面,也可以是json对象和json字符串)
@Slf4j @Controller @RequestMapping(value = "/api/demo") public class DemoController { @Autowired private DemoService demoService; @RequestMapping(value = "/register", method = RequestMethod.POST) public String register(String name, Integer age, String pwd, Model model, HttpServletRequest request, HttpServletResponse response)throws Exception{ try{ //打印日志 log.info(name+","+age+","+pwd); //获取注册的结果 User result = DempService.register(name, age, pwd); if(result.isSuccess()){ //将结果存到model里面,用于前端view层展示 model.addAttribute("result",result); //跳转至注册结果页面 return "registerResult"; }else{ response.setContentType("application/json; charset=utf-8"); response.getWriter().print("{\"code\":\"0002\",\"msg\":\"用户名已存在,注册失败!\"}"); } }catch (Exception e){ e.printStackTrace(); } return null; } @RequestMapping(value = "/login", method = RequestMethod.POST) public String login(String name, String pwd, Model model, HttpServletRequest request, HttpServletResponse response) throws Exception{ try{ //打印日志 log.info(name+","+pwd); //获取登录查询的结果 User result = demoServices.login(name, pwd); if(result.isSuccess()){ //将结果存到model里面,用于前端view层展示 model.addAttribute("result",result); HttpSession session = request.getSession(); session.setAttribute("name", result.getName()); session.setAttribute("password",result.getPwd()); System.out.println("登录后的sessionID:"+session.getId()); //跳转至登录结果页面 return "loginResult"; }else{ response.setContentType("application/json; charset=utf-8"); response.getWriter().print("{\"code\":\"0001\",\"msg\":\"用户名或密码错误!\"}"); } }catch (Exception e){ e.printStackTrace(); } return null; }示例
model 数据库实体层 DTO
数据库表对应的Entity类,每个字段都是表中的一列
Tips:注意属性名与数据库列名的对照
public class User { private Long id; private String username; private String password; private String identity; //getter与setter方法 //... }
service 业务层
定义后端接口的具体业务逻辑方法的实现
存放services接口与具体的实现类
- 借助dao包(即mapper)中提供的数据库相关功能,完成前端要求功能所需的数据的查询与插入,并返回相关的entity类对象。
Tips:services包的相关方法只是调用dao包的相关方法
命名规则
- 接口为XxxServices / XxxInterfaceService:只是简单地声明相关业务逻辑方法,没有别的代码和注解;
- 接口实现类为XxxServicesImpl / XxxServices,继承自XxxServices / XxxInterfaceService,需要实现这些业务逻辑方法
格式:
public Demo sercice_func(...){ Demo result = new Demo(); xxx = DemoMapper.mapper_func(...); try{ if(xxx != null){ //sql成功,成功接收返回值 result.setXxx(...); result.setMsg("成功!"); }else{ //sql失败 result.setXxx(...); result.setMsg("失败,..."); }catch (Exception e){ e.printStackTrace(); result.setMsg(e.getMessage()); } return result; }
public interface DemoInterfaceService { User register(String name, Integer age, String pwd); User login(String name, String pwd); }接口 DemoInterfaceService.java
@Service public class DemoServices ements DemoInterfaceService { @Autowired private DemoMapper demoMapper; @Override public User register(String name, Integer age, String pwd){ User existUser = demoMapper.findUserByName(name); User result = new User(); try { if (existUser != null) { result.setXxx(...); } else { demoMapper.register(name, age, pwd);//注册后再使用该名字查询用户信息 User currentRegUser = demoMapper.findUserByName(name); result.setXxx(...); } } catch (Exception e) { e.printStackTrace(); result.setMsg(e.getMessage()); } return result; } @Override public User login(String name, String pwd){ User result = new User(); result.setSuccess(false); Long userId = demoMapper.login(name,pwd); try{ if(userId != null){ result.setMsg("登录成功!"); result.setSuccess(true); //根据userId查询出当前登录用户 User currentLoginUser = demoMapper.findUserById(userId); result.setXxx(...); }else{ result.setMsg("用户名或密码不正确!"); result.setSuccess(false); } } catch (Exception e){ e.printStackTrace(); result.setMsg(e.getMessage()); } return result; } }接口实现类 DemoService.java
mapper 数据持久层 DAO
定义接口dao,声明了数据库操作的相关方法,业务逻辑层的各项功能通过dao方法实现与数据库的交互
Tips:具体的方法实现在mapper.xml中完善 方法对应id
DemoMapper.java
@Repository @Mapper public interface DemoMapper { //查询用户是否存在,若是存在则提示已存在 User findUserByName(String name); //新增用户 void register(String name, Integer age, String pwd); //用户登录--根据用户名和密码查询ID是否存在 Long login(String name, String pwd); User findUserById(Long id); }
DemoMapper.xml
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.xxx.demo.mapper.DemoMapper" > <resultMap id="DemoResultMap" type="com.xxx.Demo.Model.DemoModel" > <id column="id" property="id" jdbcType="INTEGER" /> <result column="name" property="name" jdbcType="VARCHAR" /> <result column="pwd" property="pwd" jdbcType="VARCHAR" /> <result column="age" property="age" jdbcType="INTEGER" /> </resultMap> <sql id="Base_Column_List" > id, name, age, pwd </sql> <select id="findUserByName" resultMap="BaseResultMap"> select <include refid="Base_Column_List" /> from user where name=#{name} </select> <select id="login" resultType="java.lang.Long"> select u.id from user u where u.name=#{param1} and u.pwd=#{param2} </select> <select id="findUserById" resultMap="BaseResultMap"> select * from user u where u.id=#{id} </select> <insert id="register"> insert into user (name,age,pwd) values(#{param1},#{param2},#{param3}) </insert> </mapper>
Tips:
-
- mapper的namespace属性,必须是mapper名且名称从com开始:com.xxx.xxx.XxxMapper;
- 如果要返回多个查询项,就要用resultMap,它对应一个entity类,借助类对象返回;
- mapper 中方法传入的参数,通过#{参数名}传进xml文件。
标签:顺序,String,name,pwd,result,User,编写,public,SpringBoot From: https://www.cnblogs.com/phoenixy/p/16771332.html参考:[SpringBoot 完整项目编写流程](https://www.cnblogs.com/ShineLeBlog/p/16476702.html)