redis中存储list结构数据如何处理
用到的工具类
1、序列化操作
String multiMapStr = JSON.toJSONString(multiMapList); // list转换为json字符串
Object o = JSON.parse(userList); // list转换为object
List<Map<String, String>> maps = CastBeanUtil.castListMap(JSON.parse(userList), String.class, String.class);// object转换list
List tzAreas = JSON.parseArray(res, TzArea.class); // 反序列化,json字符串转换为list
2、object转换为指定类型的map或者其他类型
使用如下工具类,可以将object转换为list《map》
java
package com.geekmice.springbootselfexercise.utils;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* @BelongsProject: spring-boot-self-exercise
* @BelongsPackage: com.geekmice.springbootselfexercise.utils
* @Author: pingmingbo
* @CreateTime: 2023-12-09 15:34
* @Description: TODO
* @Version: 1.0
*/
public class CastBeanUtil {
private CastBeanUtil() {
}
/**
* object 转换为list<map>
* @param obj 源数据
* @param kCalzz key对应class类型
* @param vCalzz value对应class类型
* @param <K>key类型
* @param <V>value类型
* @return list<map>
*/
public static <K, V> List<Map<K, V>> castListMap(Object obj, Class<K> kCalzz, Class<V> vCalzz) {
List<Map<K, V>> result = new ArrayList<>();
if (obj instanceof List<?>) {
for (Object mapObj : (List<?>) obj) {
if (mapObj instanceof Map<?, ?>) {
Map<K, V> map = new HashMap<>(16);
for (Map.Entry<?, ?> entry : ((Map<?, ?>) mapObj).entrySet()) {
map.put(kCalzz.cast(entry.getKey()), vCalzz.cast(entry.getValue()));
}
result.add(map);
}
}
return result;
}
return null;
}
}
通过字符串类型处理
list《map》形式
key:字符串
val:序列化过的字符串
java
List<Map<String, String>> multiMapList = Lists.newArrayList();
for (int i = 0; i < 5; i++) {
LinkedHashMap<String, String> itemMap = Maps.newLinkedHashMap();
itemMap.put("name", "jack" + i);
if (i % 2 == 0) {
itemMap.put("age", String.valueOf(10 + i));
itemMap.put("sex", "男");
} else {
itemMap.put("age", String.valueOf(11 + i));
itemMap.put("sex", "女");
}
multiMapList.add(itemMap);
}
String multiMapStr = JSON.toJSONString(multiMapList);
client.opsForValue().set("str:multiusers", multiMapStr, DateConstant.TIME_OF_DAY, TimeUnit.SECONDS);
String userList = client.opsForValue().get("str:multiusers");
List<Map<String, String>> maps = CastBeanUtil.castListMap(JSON.parse(userList), String.class, String.class);
log.info("maps : [{}]", maps);
list《entity》结构数据
java
List<TzArea> areaList = Lists.newArrayList();
for (int i = 0; i < 10; i++) {
TzArea item = new TzArea();
item.setAreaId((long) i);
item.setAreaName("江苏省");
item.setLevel(1);
item.setParentId(1L);
areaList.add(item);
}
client.opsForValue().set("str:multiareas", JSON.toJSONString(areaList), DateConstant.TIME_OF_DAY, TimeUnit.SECONDS);
String res = client.opsForValue().get("str:multiareas");
List<TzArea> tzAreas = JSON.parseArray(res, TzArea.class);
log.info("tzAreas : [{}]", JSON.toJSONString(tzAreas));