package com.tanpu.community.util; import com.alibaba.fastjson.JSON; import com.tanpu.community.api.beans.qo.ThemeContentQo; import com.tanpu.community.api.beans.qo.ThemeQo; import com.tanpu.community.api.enums.RelTypeEnum; import org.apache.commons.lang3.StringUtils; import java.util.ArrayList; import java.util.List; public class BizUtils { public static <T> List<T> subList(List<T> list, int start, int size) { if (list.isEmpty() || start >= list.size() || start < 0) { return new ArrayList<>(); } int realEnd = Math.min(start + size, list.size()); return list.subList(start, realEnd); } public static String getThemeContent(String keyword, ThemeQo theme) { for (ThemeContentQo paragraph : theme.content) { if (paragraph.getType().equals(RelTypeEnum.TEXT.type)) { int idx = paragraph.getValue().indexOf(keyword); if (idx == -1) { continue; } else if (idx < 30) { // 如果关键词在段落偏头部的部分,则全部返回给前端,前端自由展示 return paragraph.getValue(); } else { // 否则,保留关键词 向前20个字符 return "..." + paragraph.getValue().substring(idx - 20); } } } return ""; } }