原理
SORT key [BY pattern] [LIMIT offset count] [GET pattern [GET pattern ...]] [ASC|DESC] [ALPHA] [STORE destination]返回或保存给定列表、集合、有序集合 key 中经过排序的元素。
Redis 命令
对于如下结构：
| id | nicke | updateTime |
|---|---|---|
| 111 | jack | 1493709972068 |
| 2111 | tom | 1495437972186 |
| 2122 | marry | 1494573972186 |
Redis存储：
执行：
127.0.0.1:6379> sadd testkey 0 1 2
(integer) 3
查看：
127.0.0.1:6379> smembers testkey
1) "0"
2) "1"
3) "2"
执行：
127.0.0.1:6379> hset testkey1 data {\"id\":2111,\"nick\":\"tom\",\"updateTime\":1495437972186} updateTime 20170522152612 id 2111
查看：
127.0.0.1:6379> hgetall testkey1
1) "data"
2) "{\"id\":2111,\"nick\":\"tom\",\"updateTime\":1495437972186}"
3) "updateTime"
4) "20170522152612"
5) "id"
6) "2111"
……
查看：
127.0.0.1:6379> keys testkey*
1) "testkey2"
2) "testkey0"
3) "testkey1"
4) "testkey"
按照id降序：
127.0.0.1:6379> SORT testkey by testkey*->id get testkey*->data desc limit 0 3
1) "{\"id\":2122,\"nick\":\"marry\",\"updateTime\":1494573972186}"
2) "{\"id\":2111,\"nick\":\"tom\",\"updateTime\":1495437972186}"
3) "{\"id\":111,\"nick\":\"jack\",\"updateTime\":1493709972068}"
BY testkey*->id: 这个部分要求 Redis 从与 testkey 相关的所有键中获取 id 字段
Java 实现
生成排序列表：
/**
* generate sort list
* @param ns
* @param key
* @param list
* @param sortFileds
* @param <T>
* @return
*/
public <T> List<T> generateSortList(String ns, String key, List<T> list, String ... sortFileds) {
for (int i = 0; i < list.size(); i++) {
try {
Map<String, String> hmMap = new HashMap<>();
T t = list.get(i);
for(String sortFiled:sortFileds){
Field field = t.getClass().getDeclaredField(sortFiled);
field.setAccessible(true);
Object value = field.get(t);
if(value instanceof Date){
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
hmMap.put(field.getName(), sdf.format(value));
}else {
hmMap.put(field.getName(), value.toString());
}
}
// 源数据
hmMap.put("data", JSON.toJSONString(t));
redisTemplate.opsForHash().putAll(generateKey(ns, key) + i, hmMap);
redisTemplate.opsForSet().add(generateKey(ns, key), i + "");
} catch (NoSuchFieldException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
}
return null;
}
排序接口：
/**
* redis list sort
* @param ns
* @param key
* @param cla
* @param orderType
* @param sortfield
* @param offset
* @param count
* @param <T>
* @return
*/
@SuppressWarnings("unchecked")
public <T> List<T> sortList(String ns, String key, Class<T> cla,String orderType,String sortfield, int offset, int count) {
SortParameters.Order order = SortParameters.Order.valueOf(orderType);
SortParameters.Range range = new SortParameters.Range(offset, count);
SortQuery<String> query = SortQueryBuilder.sort(generateKey(ns, key))
.by(generateKey(ns, key) + "*->" + sortfield)
.get(generateKey(ns, key) + "*->data")
.order(order)
.limit(range)
.build();
List<Object> results = redisTemplate.sort(query);
List<T> resultList = new ArrayList<>();
for (Object result : results) {
resultList.add(JSON.parseObject((String) result, cla));
}
return resultList;
}
测试：
/**
* Created by dinozhang on 2017/5/8.
*/
public class RedisTest {
private static ApplicationContext applicationContext = new ClassPathXmlApplicationContext("redis.xml");
private static RedisTemplate<String, Object> redisTemplate = (RedisTemplate<String, Object>) applicationContext.getBean("redisTemplate");
public static void main(String[] args) {
UserDO userDo = new UserDO();
userDo.setId(111l);
userDo.setUpdateTime(new DateTime().withDayOfMonth(2).toDate());
userDo.setNick("jack");
UserDO userDo1 = new UserDO();
userDo1.setId(2111l);
userDo1.setNick("tom");
userDo1.setUpdateTime(new DateTime().withDayOfMonth(22).toDate());
UserDO userDo2 = new UserDO();
userDo2.setId(2122l);
userDo2.setNick("marry");
userDo2.setUpdateTime(new DateTime().withDayOfMonth(12).toDate());
List<UserDO> userDOs = new ArrayList<>();
userDOs.add(userDo);
userDOs.add(userDo1);
userDOs.add(userDo2);
String[] sortFields = { "id", "updateTime" };
generateSortList("testkey", userDOs, sortFields);
List<UserDO> userDOs1 = sortList("testkey", UserDO.class, "DESC", "id", 0, 5);
List<UserDO> userDOs2 = sortList("testkey", UserDO.class, "DESC", "updateTime", 0, 5);
System.out.println(userDOs1.size());
}
}
Redis配置文件
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 连接池配置 最大空闲数、最大连接数、最长等待时间、连接是否可用 -->
<bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
<property name="maxIdle" value="10" />
<property name="maxTotal" value="20" />
<property name="maxWaitMillis" value="300" />
<property name="testOnBorrow" value="true" />
</bean>
<!-- 连接配置 地址、端口 -->
<bean id="connectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" >
<property name="hostName" value="127.0.0.1" />
<property name="port" value="6379" />
<property name="password" value="" />
<property name="poolConfig" ref="poolConfig" />
</bean>
<!-- 暴露一个redisTemplate 用作redis一系列操作 -->
<bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate">
<property name="connectionFactory" ref="connectionFactory" />
<!--指定序列化方式避免key值出现\xac\xed\x00\x05t\x00-->
<property name="KeySerializer">
<bean class="org.springframework.data.redis.serializer.StringRedisSerializer"></bean>
</property>
<property name="ValueSerializer">
<bean class="org.springframework.data.redis.serializer.StringRedisSerializer"></bean>
</property>
<property name="HashKeySerializer">
<bean class="org.springframework.data.redis.serializer.StringRedisSerializer"></bean>
</property>
<property name="HashValueSerializer">
<bean class="org.springframework.data.redis.serializer.StringRedisSerializer"></bean>
</property>
</bean>
</beans>
