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package com.tanpu.community.util;
import com.tanpu.community.dao.entity.community.ThemeEntity;
import org.apache.commons.lang3.StringUtils;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
public class RankUtils {
/**
* 根据id排序主题对象（同时去重）
* @param list 主题
* @param ids 主题Id，list中可重复
* @return
*/
public static List<ThemeEntity> sortThemeEntityByIds(List<ThemeEntity> list, List<String> ids){
int count=0;
HashMap<String, Integer> indexMap = new HashMap<>();
for (String id : ids) {
//list中出现重复元素时，优化取第一次出现的顺序
if (!indexMap.containsKey(id)){
indexMap.put(id,count++);
}
}
List<ThemeEntity> collect = list.stream().filter(o -> indexMap.containsKey(o.getThemeId()))
.sorted(Comparator.comparingInt(o -> indexMap.get(o.getThemeId())))
.collect(Collectors.toList());
return collect;
}
/**
* 根据id排序主题对象（同时过滤权限）
* @param list
* @param recmdIds
* @param topicIds
* @return
*/
public static List<ThemeEntity> sortThemeEntityByIds(List<ThemeEntity> list, List<String> recmdIds, Set<String> topicIds){
List<ThemeEntity> themes = list.stream().filter(o -> {
if (StringUtils.isBlank(o.getTopicId())) return true;
return topicIds.contains(o.getTopicId());
}).collect(Collectors.toList());
return sortThemeEntityByIds(themes, recmdIds);
}
}