java后端内存分页

/**
 * @currPageNo  页面传入的页号,从一开始
 * @pageSize    每页记录数
 */
public <T> Map<String, Object> getPagingResultMap(List<T> list, Integer currPageNo, Integer pageSize) {
    Map<String, Object> retMap = new HashMap<>();

    if (list.isEmpty()) {
        retMap.put("result", Collections.emptyList());
        retMap.put("pageNo", 0);
        retMap.put("pageRowNum", 0);
        retMap.put("totalRowNum", 0);
        retMap.put("totalPageNum", 0);

        return retMap;
    }

    int totalRowNum = list.size();
    int totalPageNum = (totalRowNum - 1) / pageSize + 1;

    int realPageNo = currPageNo;
    if (currPageNo > totalPageNum) {
        realPageNo = totalPageNum;
    } else if (currPageNo < 1) {
        realPageNo = 1;
    }

    int fromIdx = (realPageNo - 1) * pageSize;
    int toIdx = realPageNo * pageSize + 1;
    
    if (realPageNo == totalPageNum && totalPageNum * pageSize > totalRowNum) {
        toIdx = totalRowNum + 1;
    }
    
    List<T> result = list.subList(fromIdx, toIdx);

    retMap.put("result", result);
    retMap.put("pageNo", realPageNo);
    retMap.put("pageRowNum", result.size());
    retMap.put("totalRowNum", totalRowNum);
    retMap.put("totalPageNum", totalPageNum);

    return retMap;
}
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作者:netyeaxi
来源:CSDN
原文:https://blog.csdn.net/netyeaxi/article/details/78866370
版权声明:本文为博主原创文章,转载请附上博文链接!

posted @ 2019-06-20 09:45  生命留下了遗憾  阅读(1752)  评论(0编辑  收藏  举报