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HBase的Scan查询功能（setStartRow, setStopRow），通过这两个方法，可以实现小范围的扫描，扫描的规则是[startRowKey,endRowKey)，扫描的结果是起始行包括在内，终止行不包括在内。但rowkey的存储顺序是按照rowkey的ASCAII值排序，正常情况下是将ASCAII码值小的先查出来。要实现倒序查询，需要将startRow设置为终止行，endRow设置为起始行 ，然后设置scan.setReversed(true)即可实现倒序查询;
ResultScanner scanner;
Scan scan = new Scan();
scan.addFamily(Bytes.toBytes(familyName));
//过滤掉msgRecType=3的行
SingleColumnValueFilter filter = new SingleColumnValueFilter(Bytes.toBytes("c"),
Bytes.toBytes("msgRecType"), CompareFilter.CompareOp.NOT_EQUAL, new
SubstringComparator("3"));
filter.setFilterIfMissing(true);
Filter skipFilter = new SkipFilter(filter);
scan.setFilter(skipFilter);
if(order == 0){ //升序查询
scan.setStartRow(Bytes.toBytes(startKey));
scan.setStopRow(Bytes.toBytes(endKey));
}
if(order == 1){ //倒序查询
scan.setStartRow(Bytes.toBytes(endKey));
scan.setStopRow(Bytes.toBytes(startKey));
scan.setReversed(true); //HBase自带的方法，但需要将startRow设置为终止行，endRow设置为起始行
}
Integer firstIndex = (currentPage - 1) * pageSize; //当前查询页起始index
try {
scanner = table.getScanner(scan);
if (firstIndex > 0) {
scanner.next(firstIndex);
}
Result[] results = scanner.next(pageSize);
Long total = findCount(tableName,familyName,startKey,endKey); //total为查询总条数
for (Result result : results) {
List<Cell> cellList = result.listCells();
Map<String, String> resultMap = new HashMap<>();
for (Cell cell : cellList) {
resultMap.put(Bytes.toStringBinary(CellUtil.cloneQualifier(cell)), new String(CellUtil.cloneva lue(cell),"UTF-8"));
}
resultList.add(resultMap);
}