Spring Data JPA进阶学习与Swagger

1.初始Swagger

swagger的由来

• 随着互联网技术的发展，现在的网站架构基本都由原来的后端渲染，变成了：前端渲染、先后端分离的形态，而且前端技术和后端技术在各自的道路上越走越远。
• 前端和后端的唯一联系，变成了API接口；API文档变成了前后端开发人员联系的纽带，变得越来越重要，swagger就是一款让你更好的书写API文档的框架。

添加依赖

• 在pom.xml中引入依赖

<dependency>
<groupId>com.spring4all</groupId>
<artifactId>swagger-spring-boot-starter</artifactId>
<version>1.8.0.RELEASE</version>
</dependency>

2.Spring Data JPA进阶练习

1.持久化类

package com.example.springdatajpa.entity; 

import lombok.Data; 

import javax.persistence.Column; 
import javax.persistence.Entity; 
import javax.persistence.GeneratedValue; 
import javax.persistence.Id; 
import java.io.Serializable; 

@Entity 
@Data 
public class SysUser implements Serializable { 
@Id 
@GeneratedValue 
private Long id; 

@Column(nullable = false) 
private String account; 

@Column(nullable = false) 
private String password; 

private String nickname; 

private Integer fans; 

public SysUser(String account, String password, String nickname,
Integer fans) {

this.account = account; 
this.password = password; 
this.nickname = nickname; 
this.fans = fans; 
} 

public SysUser() { 
} 
} 

2.repository接口

package com.example.springdatajpa.dao; 

import com.example.springdatajpa.entity.SysUser; 
import org.springframework.data.jpa.repository.JpaRepository; 
import org.springframework.data.jpa.repository.Query; 
import org.springframework.data.repository.query.Param; 

import java.util.List; 

/** 
* 继承JpaRepository，默认已经具备创建（save）、更新（save）、删除（delete）、查
询（findAll、findOne）等基本功能

*/ 
public interface UserRepository extends JpaRepository<SysUser, Long> { 

//根据账号精确查询用户，采用的是通过解析方法名创建查询 
SysUser findByAccount(String account); 

//根据昵称关键词查询用户，采用的是通过解析方法名创建查询 
List<SysUser> findByNicknameLike(String keywords); 

//查询昵称含有指定关键词并且按粉丝数降序排列，采用自定义的JPQL查询 
@Query("from SysUser u where u.nickname like
CONCAT('%',:nickname,'%') order by u.fans desc ")

List<SysUser> findUsers(@Param("nickname") String nickname); 23
} 

3.单元测试

package com.example.springdatajpa.dao; 

import com.example.springdatajpa.entity.SysUser; 
import org.junit.Test; 
import org.junit.runner.RunWith; 
import org.springframework.boot.test.context.SpringBootTest; 
import org.springframework.test.context.junit4.SpringRunner; 

import javax.annotation.Resource; 

import java.util.List; 


@RunWith(SpringRunner.class) 
@SpringBootTest 
public class UserRepositoryTest { 
@Resource 
private UserRepository userRepository; 

@Test 
public void initData() { 
// 创建6条用户记录 
SysUser[] users = { 
new SysUser("aaa@qq.com", "111", "简书大学堂", 1129), 
new SysUser("bbb@qq.com", "222", "宇文欢", 897), 
new SysUser("ccc@qq.com", "333", "一只枝", 776), 
new SysUser("ddd@qq.com", "444", "lostdays", 666), 
new SysUser("eee@qq.com", "555", "十七楼的安素", 433), 
new SysUser("fff@qq.com", "666", "徐林Grace", 112) 
}; 
for (int i = 0; i < 6; i++) { 
userRepository.save(users[i]); 
} 
} 

@Test 
public void findAll() { 
List<SysUser> users = userRepository.findAll(); 
users.forEach(sysUser -> System.out.println(sysUser)); 
} 

@Test 
public void findOne() { 
SysUser user = userRepository.findById(21L).get(); 
System.out.println(user); 
} 

@Test 
public void findByAccount() { 
SysUser sysUser = userRepository.findByAccount("aaa@qq.com"); 
System.out.println(sysUser); 
} 

@Test 
public void findByNicknameLike() { 
List<SysUser> users = userRepository.findByNicknameLike("%@qq%"); 
users.forEach(user -> System.out.println(user)); 
} 

@Test 
public void findUsers() { 
List<SysUser> users = userRepository.findUsers("简"); 
users.forEach(sysUser -> System.out.println(sysUser)); 
} 

} 

4.service层

package com.example.springdatajpa.service; 

import com.example.springdatajpa.entity.SysUser; 

import java.util.List; 

public interface UserService { 

//查询所有用户 
List<SysUser> getAll(); 

//根据id查询用户 
SysUser getUser(Long id); 

//根据账号精确查询用户 
SysUser getUserByAccount(String account); 

//根据昵称关键词查询用户 
List<SysUser> getUsersByNicknameLike(String keywords); 

//查询昵称含有指定关键词并且按粉丝数降序排列 
List<SysUser> getUsersOrderByFans(String nickname); 

} 

实现类

package com.example.springdatajpa.service.impl; 

import com.example.springdatajpa.dao.UserRepository; 
import com.example.springdatajpa.entity.SysUser; 
import com.example.springdatajpa.service.UserService; 
import org.springframework.stereotype.Service; 

import javax.annotation.Resource; 
import java.util.List; 

@Service 
public class UserServiceImpl implements UserService { 
@Resource 
private UserRepository userRepository; 


@Override 
public List<SysUser> getAll() { 
return userRepository.findAll(); 
} 

@Override 
public SysUser getUser(Long id) { 
return userRepository.findById(id).get(); 
} 

@Override 
public SysUser getUserByAccount(String account) { 
return userRepository.findByAccount(account); 
} 

@Override 
public List<SysUser> getUsersByNicknameLike(String keywords) { 
return userRepository.findByNicknameLike(keywords); 
} 


@Override 
public List<SysUser> getUsersOrderByFans(String nickname) { 
return userRepository.findUsers(nickname); 
} 
}

5.controller层

package com.example.springdatajpa.controller; 

import com.example.springdatajpa.entity.SysUser; 
import com.example.springdatajpa.service.UserService; 
import org.springframework.web.bind.annotation.*; 

import javax.annotation.Resource; 
import java.util.List; 

@RestController 
@RequestMapping(value = "/user") 
public class UserController { 
@Resource 
private UserService userService; 

/** 
* 映射 /user/all请求，获取所有用户数据 
* @return 
*/ 
@GetMapping("/all") 
public List<SysUser> getAll() { 
return userService.getAll(); 
} 

/** 
* 映射 /user/{id}请求，获取指定id的用户数据 ，具体的id值可以直接放在地址url
里传递

* @return 
*/ 
@GetMapping("/{id}") 
public SysUser getUser(@PathVariable Long id) { 
return userService.getUser(id); 
} 

/** 
* 映射 /user/account请求，获取指定账户的用户数据，需要传递一个用户账号参数 
* @return 
*/ 
@GetMapping("/account") 
public SysUser getUserByAccount(@RequestParam String account) { 
return userService.getUserByAccount(account); 
} 

/** 
* 映射 /user/nickname请求，获取根据昵称关键词查询的用户数据，需要传递一个昵
称关键词作为参数，且因为是第二种方法，参数需要：%简书%的形式

* @return 
*/ 
@GetMapping("/nickname") 
public List<SysUser> getUsersByNicknameLike(@RequestParam String
keywords) {

return userService.getUsersByNicknameLike(keywords); 
} 

/** 
* 映射 /user/order请求，获取根据昵称关键词查询并按粉丝数降序排列的用户数据，
需要传递一个昵称关键词作为参数，自己写的查询，参数只需要传递字符串

* @return 
*/ 
@GetMapping("/order") 
public List<SysUser> getUsersOrderByFans(@RequestParam String
nickname) {

return userService.getUsersOrderByFans(nickname); 
} 
} 

6. swagger接⼝⽂档⻚⾯