#Java篇：java项目init和写接口流程步骤详细

idea里面 file—new-project

Server url

https://start.aliyun.com

目录结构

数据库链接项目配置

application.yml

server:
  port: 8888
spring:
    datasource:
     url: jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=UTF-8
     username: root
     password: root
     driver-class-name: com.mysql.cj.jdbc.Driver

主要目录

controller

service

impl实现类

model

mapper

java接口详细描述

创建文件顺序

model—Role
mapper—RoleMapper 继承Role
service----IRoleService 继承Role
service(impl)—RoleServiceImpl 实现IRoleService
controller—RoleController 实现接口返回前端

model—Role

// model---Role
package com.xiaolibao.javacxyxiaolibao.model;

import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

@TableName("role_info")
@Data
public class Role {
    private String id;
    private String name;
    private String phone;
}

mapper—RoleMapper

// mapper---RoleMapper
package com.xiaolibao.javacxyxiaolibao.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.xiaolibao.javacxyxiaolibao.model.Role;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public  interface RoleMapper extends BaseMapper<Role> {

}

service----IRoleService

// service----IRoleService 继承Role
package com.xiaolibao.javacxyxiaolibao.service;

import com.baomidou.mybatisplus.extension.service.IService;
import com.xiaolibao.javacxyxiaolibao.model.Role;

import java.util.List;

public interface IRoleService extends IService<Role>  {
    List<Role> test();
}

impl— RoleServiceImpl

// RoleServiceImpl 实现IRoleService
package com.xiaolibao.javacxyxiaolibao.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.xiaolibao.javacxyxiaolibao.mapper.RoleMapper;
import com.xiaolibao.javacxyxiaolibao.model.Role;
import com.xiaolibao.javacxyxiaolibao.service.IRoleService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class RoleServiceImpl extends ServiceImpl<RoleMapper, Role> implements IRoleService {
    @Autowired
    private RoleMapper roleMapper;

    @Override
    public List<Role> test() {
        List<Role> roles = roleMapper.selectList(null);
        return roles;
    }
}

####controller— RoleController

// RoleController 实现接口返回前端
package com.xiaolibao.javacxyxiaolibao.controller;

import com.xiaolibao.javacxyxiaolibao.model.Role;
import com.xiaolibao.javacxyxiaolibao.service.IRoleService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
@RequestMapping("/role")
public class RoleController {
 @Autowired
    private IRoleService roleService;
 @GetMapping("/test")
    public List<Role> test(){
      List<Role> test = roleService.test();
      return  test;
    }
}