Springboot2快速集成

1. 通过一个实例快速搭建SSM。
2. 通过实例来看看各个环节的最佳实践。
3. 如何使用业务异常。
4. 如何设计一个对前端友好的接口。
5. 通过单元测试使你的工作更加轻松和安全。
6. 简单聊聊代码规范。
7. 利用CI/CD来帮助你处理繁杂的重复性工作。

源码地址 https://github.com/bestaone/Mybatis4Springboot

Spring5、springboot2近况

---

• spring5

  最大的亮点是 Spring webflux。Spring webflux 是一个新的非堵塞函数式 Reactive Web 框架，可以用来建立异步的，非阻塞，事件驱动的服务，并且扩展性非常好。

• springboot

  集成了大量常用的第三方库配置（例如Jackson, JDBC, Mongo, Redis, Mail等等），Spring Boot应用中这些第三方库几乎可以零配置的开箱即用（out-of-the-box），大部分的Spring Boot应用都只需要非常少量的配置代码，开发者能够更加专注于业务逻辑。

一分钟helloworld看看新姿势

---

• 创建文件

  新建项目Demo

  创建文件 pom.xml

  src/main/java、src/main/resources、src/test/java

  创建包 hello

pom.xml

    4.0.0
    com.caad.springboot.test
    Demo
    jar
    1.0-SNAPSHOT

    
        org.springframework.boot
        spring-boot-starter-parent
        2.0.0.M7
    
    
    
        
            org.springframework.boot
            spring-boot-starter-web
        
    
    
    
        
            spring-milestones
            Spring Milestones
            https://repo.spring.io/libs-milestone
            
                false
            
        
    

    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
        
    

    
        
            spring-snapshots
            Spring Snapshots
            http://repo.spring.io/snapshot
            
                true
            
        
        
            spring-milestones
            Spring Milestones
            http://repo.spring.io/milestone
            
                false
            
        
        
            spring-releases
            Spring Releases
            http://repo.spring.io/release
            
                false
            
        
    

创建启动类 SampleController.java

package hello;

import org.springframework.boot.*;
import org.springframework.boot.autoconfigure.*;
import org.springframework.stereotype.*;
import org.springframework.web.bind.annotation.*;

@Controller
@EnableAutoConfiguration
public class SampleController {

    @RequestMapping("/")
    @ResponseBody
    String home() {
        return "Hello World!";
    }

    public static void main(String[] args) throws Exception {
        SpringApplication.run(SampleController.class, args);
    }
    
}

• 运行

mvn install
mvn spring-boot:run

• 测试

http://localhost:8080/

标准的三层模型

---

• 目录结构

- com.caad.springboot.test
    - controller
        - UserController.java
    - service
        - UserService.java
    - dao
        - UserDao.java
    - domain
        - enums
            - GenderType.java
        - User.java
    - Application.java

为什么service不使用interface了

• 代码实现

public class User {

    private Long id;
    private String name;
    private GenderType gender;
    private Date createTime;

}

public enum GenderType {

    MALE,
    FEMALE,
    UNKNOW,
    OTHER;

}

@RestController
@RequestMapping(value = "/user")
public class UserController {

    @Autowired
    private UserService userService;

    @RequestMapping(value = "/find/{id}")
    public User find(@PathVariable("id") Long id) {
        User user = userService.findById(id);
        return user;
    }

}

@Service
public class UserService {

    @Autowired
    private UserDao dao;

    public User findById(Long id) {
        return dao.findById(id);
    }

}

@Repository
public class UserDao {

    public User findById(Long id) {
        User user = new User();
        user.setId(123L);
        user.setName("test");
        user.setGender(GenderType.UNKNOW);
        user.setCreateTime(new Date());
        return user;
    }

}

• 测试
  http://localhost:8080/user/find/1

集成mybatis

---

• 添加依赖maven依赖

    mysql
    mysql-connector-java



    org.mybatis.spring.boot
    mybatis-spring-boot-starter
    1.3.1

• 添加springboot配置文件 application.yml

server.port: 8888

spring.datasource:
  driverClassName: com.mysql.jdbc.Driver
  url: jdbc:mysql://172.16.2.154:3307/aqs_test?useUnicode=true&characterEncoding=utf-8
  username: 
  password: r5rD6a8NBnWP9NGs

mybatis:
  config-locations: classpath:mybatis/mybatis-config.xml
  mapper-locations: classpath:mybatis/mapper/*.xml
  type-aliases-package: com.caad.springboot.test.domain

• 添加mybatis配置文件 mybatis-config.xml

• 修改DAO注解

@Mapper
public interface UserDao {

    @Select("SELECT id, name, gender, createTime FROM User where id=#{id}")
    public User findById(Long id);

}

• 初始化数据库

CREATE TABLE `User` (
  `id` bigint(20) NOT NULL,
  `name` varchar(20) DEFAULT NULL,
  `gender` varchar(20) DEFAULT NULL,
  `createTime` datetime DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

• CRUD

@Insert("INSERT INTO User(id,name,gender,createTime) VALUES(#{id}, #{name}, #{gender}, #{createTime})")
void insert(User user);

@Delete("DELETE FROM User WHERE id = #{id}")
void delete(Long id);

@Update("UPDATE User SET name=#{name},gender=#{gender},createTime=#{createTime} WHERE id =#{id}")
void update(User user);

@Select("SELECT id, name, gender, createTime FROM User")
List findAll();

@Service
public class UserService {

    @Autowired
    private UserDao dao;

    public User findById(Long id) {
        return dao.findById(id);
    }

    public User save(User user){
        if(user==null) return null;
        if(user.getId()==null){
            dao.insert(user);
        }else {
            dao.update(user);
        }
        return user;
    }

    public void remove(Long id){
        dao.delete(id);
    }

    public List findAll(){
        return dao.findAll();
    }

}

• 添加单元测试依赖

    org.springframework.boot
    spring-boot-starter-test

• 编写测试类

@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class)
public class UserServiceTest {

    @Autowired
    public UserService service;

    @Test
    public void CRUDTest() {

        //CREATE
        User o = new User();
        o.setCreateTime(new Date());
        o.setName("CRUDTest");
        service.save(o);
        Assert.assertNotNull(o.getId());

        //READ
        o = service.findById(o.getId());
        Assert.assertNotNull(o.getId());

        //UPDATE
        o.setName("CRUDTest1");
        service.save(o);
        o = service.findById(o.getId());
        Assert.assertTrue(o.getName().equals("CRUDTest1"));

        //DELETE
        service.remove(o.getId());
        o = service.findById(o.getId());
        Assert.assertNull(o);

    }
    
}

• 引入主键生成器 IdGenerator

• XML方式实现DAO接口

List findByName(String name);

• 添加mapper文件（文件名需要和接口名一致）

    
        
        
        
        
    

    
        id, name, gender, createTime
    

    
        SELECT  FROM User WHERE name = #{name}
    

• 添加logback.xml配置,查看sql

    
    
    
    
    
    

    
    
    
    
    

    
    
        
            ${LOG_PATTERN}
        
    

    
        
            ${LOG_PATTERN}
        
        ${LOG_FILE}
        
            ${LOG_FILE}.%i.zip
            1
            10
        
        
            10MB
        
    

    
    
        
        
    

• 添加测试代码

List list = service.findByName(o.getName());
Assert.assertNotNull(list.size()>0);

• 几次失误，导致了脏数据，映入测试回滚

@Transactional
@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class)
public class UserServiceTest {

• 添加controller端findAll接口

@RequestMapping(value = "/getAll")
public List getAll() {
    return userService.findAll();
}

• 引入分页插件

    com.github.pagehelper
    pagehelper-spring-boot-starter
    1.2.3

@RequestMapping(value = "/pageAll")
public PageInfo pageAll() {
    PageHelper.startPage(1, 5);
    List list = userService.findAll();
    return new PageInfo(list);
}

如何写一个对用户友好的接口

---

• 问题

  用户有哪些，测试人员、开发人员、浏览器、调试工具、客户端程序等

  开发人员拿到没有统一格式的数据，没办法分层处理

  为了方便框架解析、分层控制，有必要规范输入输出格式

• 事例 getUser

{
    "id": 4354523,
    "name":"张三"
}

{
    "errorCode":-10000,
    "message":"未登录"
}

{
    "bizCode":-1,
    "message":"所查用户不存在"
}

{
    "code": 1,
    "message":""，
    "data"：{
        "id": 4354523,
        "name":"张三"
    }
}

{
    "code": -10000,
    "message":"未登录"，
    "data"：{
    }
}

{
    "code": -1,
    "message":"所查用户不存在"，
    "data"：{
    }
}

• 引入ViewData

public class ViewData implements Serializable{

    private static final long serialVersionUID = 7408790903212368997L;

    private Integer code = 1;

    private String message;

    private T data;

    public ViewData(){}

    public ViewData(T obj) {
        this.data = obj;
    }

    public ViewData(Integer code, String message) {
        this.code = code;
        this.message = message;
    }

    public ViewData(Integer code, String message, T obj) {
        this.code = code;
        this.message = message;
        this.data = obj;
    }

    public static  ViewData ok() {
        return new ViewData<>();
    }

    public static  ViewData ok(T obj) {
        return new ViewData<>(obj);
    }

    public static  ViewData error(String msg) {
        return new ViewData<>(-1, msg);
    }

    public static  ViewData error(Integer code, String msg) {
        return new ViewData<>(code, msg);
    }

}

• 对输出数据进行格式化

package com.caad.springboot.test.api.resp;

public class UserResp {

    private Long id;
    private String username;
    private Date createTime;
    private GenderType gender;

}

@RequestMapping(value = "/find/{id}")
public ViewData find(@PathVariable("id") Long id) {
    User user = userService.findById(id);
    UserResp resp = new UserResp();
    resp.setCreateTime(user.getCreateTime());
    resp.setGender(user.getGender());
    resp.setUsername(user.getName());
    resp.setId(user.getId());
    return ViewData.ok(resp);
}

• 使用@RequestBody对输入参数格式化

package com.caad.springboot.test.api.requ;

public class UserRequ {

    private Long id;
    private String name;
    private String gender;

    public UserRequ() { }

    public UserRequ(Long id, String name, String gender) {
        this.id = id;
        this.name = name;
        this.gender = gender;
    }

}

@RequestMapping(value = "/update")
public ViewData update(@RequestBody UserRequ userRequ) {
    User user = userService.findById(userRequ.getId());
    user.setName(userRequ.getName());
    user.setGender(GenderType.valueOf(userRequ.getGender()));
    userService.save(user);
    return ViewData.ok(user);
}

http://localhost:8080/user/update
{
    "id":1,
    "name":"hi boy",
    "gender":"MALE"
}

• 自定义数据转换

@Component
public class JsonDataSerializer extends JsonSerializer