Redis是一个key-value数据库,支持存储的value类型包括string(字符串)、list(链表)、set(集合)、zset(sorted set --有序集合)和hash(哈希类型)。在Java中,使用较为广泛的客户端有Redisson、Jedis。Spring Data Redis模块默认使用Jedis。
开发环境:IntelliJ IDEA 2019.2.2
Spring Boot版本:2.1.8
一、项目构建
1、新建一个名称为demo的Spring Boot项目。
2、pom.xml
org.springframework.boot
spring-boot-starter-web
org.springframework.boot
spring-boot-starter-data-redis
org.springframework.boot
spring-boot-starter-test
test
org.springframework.boot
spring-boot-devtools
3、application.yml
配置Redis的相关属性。
spring:
redis:
port: 6379
password: 123456
host: localhost
二、实体类
1、User.java
映射Redis的数据:
(1) 类使用@RedisHash注解表示User对象会以hash类型保存;
(2) 字段id使用@Id注解表示自动生成guid;
(3) 字段使用@Indexed表示建立索引,在方法名查询时需要设置此注解;
package com.example.demo.entity;
import org.springframework.data.annotation.Id;
import org.springframework.data.redis.core.RedisHash;
import org.springframework.data.redis.core.index.Indexed;
@RedisHash("user")
public class User {
@Id
private String id;
@Indexed
private String name;
@Indexed
private Integer age;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
}
三、数据访问层
1、数据访问层 UserRepository.java
继承CrudRepository可以不需要任何实现,拥有基本的CRUD操作。也可以手动添加代码实现方法名查询。
package com.example.demo.repository;
import com.example.demo.entity.User;
import org.springframework.data.repository.CrudRepository;
import java.util.List;
public interface UserRepository extends CrudRepository {
//方法名查询:根据字段name查询
List findByName(String name);
//方法名查询:根据字段name和age的And查询
List findByNameAndAge(String name, Integer age);
//方法名查询:根据字段name和age的Or查询
List findByNameOrAge(String name, Integer age);
}
四、业务层
1、UserRepository.java
package com.example.demo.service;
import com.example.demo.entity.User;
import com.example.demo.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
@Service
public class UserService {
@Autowired
UserRepository userRepository;
public List getUsers(){
Iterable users = userRepository.findAll();
List datas = new ArrayList();
for(Iterator it = users.iterator(); it.hasNext();){
User u = it.next();
datas.add(u);
}
return datas;
}
public void save(User user) {
userRepository.save(user);
}
public List findByName(String name){
return userRepository.findByName(name);
}
public List findByNameAndAge(String name, Integer age){
return userRepository.findByNameAndAge(name, age);
}
public List findByNameOrAge(String name, Integer age){
return userRepository.findByNameOrAge(name, age);
}
}
五、控制器
1、UserController.java
package com.example.demo;
import com.example.demo.entity.User;
import com.example.demo.service.UserService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
import java.util.List;
@RestController
public class UserController {
@Resource
UserService userService;
@RequestMapping("/save")
public String save(){
for(int i=1;i<=20;i++){
User user = new User();
user.setName("a" + i);
user.setAge(i);
userService.save(user);
}
return "添加成功";
}
@RequestMapping("/getUsers")
public List getUsers(){
List users = userService.getUsers();
return users;
}
@RequestMapping("/findByName")
public List findByName(String name){
return userService.findByName(name);
}
@RequestMapping("/findByNameAndAge")
public List findByNameAndAge(String name, Integer age){
return userService.findByNameAndAge(name, age);
}
@RequestMapping("/findByNameOrAge")
public List findByNameOrAge(String name, Integer age){
return userService.findByNameOrAge(name, age);
}
}
启动服务器,浏览器访问:http://localhost:8080/save 生成20条测试数据,访问http://localhost:8080/getUsers,页面显示如下:
[{"id":"8da6f5ad-b24c-4725-9c69-4d709369eac7","name":"a14","age":14},{"id":"b62b2028-4d41-41be-aeff-e2b56776dd87","name":"a10","age":10},{"id":"c8330a2a-902b-4db9-b262-65d182027eac","name":"a6","age":6},{"id":"cc7b5a91-0ca6-4577-891a-835a1cebef6f","name":"a11","age":11},{"id":"09f8f2e3-2cf8-48f7-a535-1897b7cc0f35","name":"a1","age":1},{"id":"3344413f-8128-42ad-8343-304005c87e5f","name":"a7","age":7},{"id":"db74f020-f3e3-4422-8013-c515b9d8551d","name":"a5","age":5},{"id":"7fc46621-ecaf-47c6-bae3-f2061104d802","name":"a2","age":2},{"id":"dcdcdda0-bab0-450a-b6e6-fdce410b01fd","name":"a8","age":8},{"id":"b456f4fd-158f-43e9-86cf-0340b809ffab","name":"a12","age":12},{"id":"4ffb6019-21b1-4880-8ec3-2703f561d028","name":"a15","age":15},{"id":"7e45d738-7a31-4b24-928e-a9da3583ef6d","name":"a4","age":4},{"id":"7992e502-4049-4d40-bc35-aab72adbe335","name":"a19","age":19},{"id":"3df7b2ac-6bb0-496d-91d2-05ac763e5f68","name":"a13","age":13},{"id":"7c94edba-f91e-42fe-b8b4-7c6a9ba82747","name":"a3","age":3},{"id":"39402099-17ba-4368-ac23-dd5e9fe1d8ae","name":"a17","age":17},{"id":"e49750d6-ce80-4764-87d3-1566d9263360","name":"a18","age":18},{"id":"499e1a9a-b947-4eec-8d37-d1cdf7ac1179","name":"a16","age":16},{"id":"04f0cb4e-c17b-4b4e-b135-e6c222aace21","name":"a9","age":9},{"id":"ac48ce35-5a38-48b8-90b9-6b999c3fd242","name":"a20","age":20}]
其它控制器方法略。