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hbase scan的java操作

hbase scan的java操作

作者: 会飞的蜗牛66666 | 来源:发表于2018-10-24 13:29 被阅读0次

    public class HbaseTest {

    public static void main(String[] args) throws Exception {
        //构建基本信息
        String table = "t_userBehavior2";
        final TableName tableName = TableName.valueOf(table);
        final HTable hTable = new HTable(tableName, HBaseUtil.getConnection());
        final Scan scan = new Scan();
    
        //查询出小于某个rk的全部数据
        System.out.println("小于等于DD4400000047344000007497818085B0的行");
        Filter filter1 = new RowFilter(CompareFilter.CompareOp.LESS_OR_EQUAL,
                new BinaryComparator("DD4400000047344000007497818085B0".getBytes()));
        scan.setFilter(filter1);
        ResultScanner scanner1 = hTable.getScanner(scan);
        for (Result res : scanner1) {
            System.out.println(res);
        }
        scanner1.close();
        System.out.println("--------------------------------------------------------------------");
    
        //正则匹配rk
        System.out.println("正则获取结尾为85B0的行");
        final RowFilter filter2 = new RowFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator(".*85B0"));
        scan.setFilter(filter2);
        final ResultScanner scanner2 = hTable.getScanner(scan);
        for (Result res : scanner2) {
            System.out.println(res);
        }
        scanner2.close();
        System.out.println("--------------------------------------------------------------------");
    
        //rk包含某些字符串的所有行
        System.out.println("包含有DD4400000047的行");
        Filter filter3 = new RowFilter(CompareFilter.CompareOp.EQUAL,
                new SubstringComparator("DD4400000047"));
        scan.setFilter(filter3);
        ResultScanner scanner3 = hTable.getScanner(scan);
        for (Result res : scanner3) {
            System.out.println(res);
        }
        scanner3.close();
        System.out.println("--------------------------------------------------------------------");
    
        //判断rk的开头信息的所有行
        System.out.println("开头是DD4400的");
        Filter filter4 = new RowFilter(CompareFilter.CompareOp.EQUAL,
                new BinaryPrefixComparator("DD4400".getBytes()));
        scan.setFilter(filter4);
        ResultScanner scanner4 = hTable.getScanner(scan);
        for (Result res : scanner4) {
            System.out.println(res);
        }
        scanner3.close();
        System.out.println("----------------------------------------------------");
    

    /***

    • RowFilter用于过滤row key,过滤的条件如下:
      Operator Description
      LESS 小于
      LESS_OR_EQUAL 小于等于
      EQUAL 等于
      NOT_EQUAL 不等于
      GREATER_OR_EQUAL 大于等于
      GREATER 大于
      NO_OP 排除所有

    Comparator Description比较器:
    BinaryComparator 使用Bytes.compareTo()比较
    BinaryPrefixComparator 和BinaryComparator差不多,从前面开始比较
    NullComparator Does not compare against an actual value but whether a given one is null, or not null.
    BitComparator Performs a bitwise comparison, providing a BitwiseOp class with OR, and XORoperators.
    RegexStringComparator 正则表达式
    SubstringComparator 把数据当成字符串,用contains()来判断
    *scan.setFilter(new PrefixFilter(rowPrifix.getBytes()));根据rk的前缀来进行过滤出所有的行
    *设定限制范围,查询出该范围内的所有行

    • scan.setStartRow(getBytes(startRow));

    • scan.setStopRow(getBytes(stopRow));
      */

       scan.setStartRow(Bytes.toBytes("000000000"));
      

    // scan.setStopRow(Bytes.toBytes("235959999"));
    // scan.setFilter(new PrefixFilter(rowPrifix.getBytes()));
    ResultScanner rs = hTable.getScanner(scan);
    for (Result r : rs) {
    KeyValue[] kv = r.raw();
    for (int i = 0; i < kv.length; i++) {
    final String rk = new String(kv[i].getRow());
    final Result resut = HBaseUtil.getRow(table, rk.getBytes());
    final List<Cell> cellList = resut.listCells();
    for (Cell cell : cellList) {
    final String value = new String(cell.getValue());
    System.out.println(value);
    }
    System.out.print(new String(kv[i].getRow()) + " ");
    System.out.print(new String(kv[i].getFamily()) + ":");
    System.out.print(new String(kv[i].getQualifier()) + " ");
    System.out.print(kv[i].getTimestamp() + " ");
    System.out.println(new String(kv[i].getValue()));
    }

        }
    }
    

    }

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