共计 1229 个字符,预计需要花费 4 分钟才能阅读完成。
获取 ZY:Spark+ES+ClickHouse 构建 DMP 用户画像
importjava.util.Arrays;
importjava.util.Collections;
importjava.util.List;
publicclassListPageUtil{
/**
* 每页浮现条数
*/
privateintpageSize;
/**
* 总页数
*/
privateintpageCount;
/**
* 原汇合
*/
privateListdata;
publicListPageUtil(Listdata,intpageSize) {if(data ==null|| data.isEmpty()) {thrownewIllegalArgumentException("data must be not empty!");
}
this.data = data;
this.pageSize = pageSize;
this.pageCount = data.size()/pageSize;
if(data.size()%pageSize!=0){this.pageCount++;}
}
/**
* 失去分页后的数据
*
* @param pageNum 页码
* @return 分页后后果
*/
publicListgetPagedList(intpageNum) {intfromIndex = (pageNum -1) * pageSize;
if(fromIndex >= data.size()) {returnCollections.emptyList();
}
inttoIndex = pageNum * pageSize;
if(toIndex >= data.size()) {toIndex = data.size();
}
returndata.subList(fromIndex, toIndex);
}
publicintgetPageSize() {returnpageSize;}
publicListgetData() {returndata;}
publicintgetPageCount() {returnpageCount;}
publicstaticvoidmain(String[] args) {Integer[] array = {1,2,3,4,5,6,7,8,9,10,11,12};
Listlist = Arrays.asList(array);
ListPageUtilpager =newListPageUtil(list,10);
System.out.println(pager.getPageCount());
Listpage1 = pager.getPagedList(1);
System.out.println(page1);
Listpage2 = pager.getPagedList(2);
System.out.println(page2);
Listpage3 = pager.getPagedList(3);
System.out.println(page3);
}
}
正文完