HBase Filter 过滤器之RowFilter详解

缺乏、安全感 2022-09-12 01:53 257阅读 0赞

**前言：**本文详细介绍了HBase RowFilter过滤器Java&Shell API的使用，并贴出了相关示例代码以供参考。RowFilter 基于行键进行过滤，在工作中涉及到需要通过HBase Rowkey进行数据过滤时可以考虑使用它。比较器细节及原理请参照之前的更文：[HBase Filter 过滤器之比较器 Comparator 原理及源码学习][HBase Filter _ Comparator]

## 一。Java Api ##

**头部代码**

public class RowFilterDemo {
    
        private static boolean isok = false;
        private static String tableName = "test";
        private static String[] cfs = new String[]{"f"};
        private static String[] data = new String[]{"row-ac:f:c1:v1", "row-ab:f:c2:v2", "row-bc:f:c3:v3", "row-abc:f:c4:v4"};
    
        public static void main(String[] args) throws IOException {
    
            MyBase myBase = new MyBase();
            Connection connection = myBase.createConnection();
            if (isok) {
                myBase.deleteTable(connection, tableName);
                myBase.createTable(connection, tableName, cfs);
                myBase.putRows(connection, tableName, data); // 造数据
            }
            Table table = connection.getTable(TableName.valueOf(tableName));
            Scan scan = new Scan();

**中部代码**  
向右滑动滚动条可查看输出结果。

### 1. BinaryComparator 构造过滤器 ###

RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes("row-ac"))); // [row-ac]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.NOT_EQUAL, new BinaryComparator(Bytes.toBytes("row-ac"))); // [row-ab, row-abc, row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.GREATER, new BinaryComparator(Bytes.toBytes("row-ac"))); // [row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.GREATER_OR_EQUAL, new BinaryComparator(Bytes.toBytes("row-ac"))); // [row-ac, row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.LESS, new BinaryComparator(Bytes.toBytes("row-ac"))); // [row-ab, row-abc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryComparator(Bytes.toBytes("row-ac"))); // [row-ab, row-abc, row-ac]

### 2. BinaryPrefixComparator 构造过滤器 ###

RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes("row-a"))); // [row-ab, row-abc, row-ac]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.NOT_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("row-a"))); // [row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.GREATER, new BinaryPrefixComparator(Bytes.toBytes("row-a"))); // [row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.GREATER_OR_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("row-a"))); // [row-ab, row-abc, row-ac, row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.LESS, new BinaryPrefixComparator(Bytes.toBytes("row-a"))); // []
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("row-a"))); // [row-ab, row-abc, row-ac]

### 3. SubstringComparator 构造过滤器 ###

RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.EQUAL, new SubstringComparator("ab")); // [row-ab, row-abc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.NOT_EQUAL, new SubstringComparator("ab")); // [row-ac, row-bc]

### 4. RegexStringComparator 构造过滤器 ###

RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.NOT_EQUAL, new RegexStringComparator("abc")); // [row-ab, row-ac, row-bc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator("abc")); // [row-abc]
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator("a")); // [row-ab, row-abc, row-ac]

### 5. NullComparator 构造过滤器 ###

RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.EQUAL, new NullComparator()); // []
            RowFilter rowFilter = new RowFilter(CompareFilter.CompareOp.NOT_EQUAL, new NullComparator()); // [row-ab, row-abc, row-ac, row-bc]

**尾部代码**

scan.setFilter(rowFilter);
            ResultScanner scanner = table.getScanner(scan);
            Iterator<Result> iterator = scanner.iterator();
            LinkedList<String> rowkeys = new LinkedList<>();
            while (iterator.hasNext()) {
                Result result = iterator.next();
                String rowkey = Bytes.toString(result.getRow());
                rowkeys.add(rowkey);
            }
            System.out.println(rowkeys);
            scanner.close();
            table.close();
            connection.close();
        }
    }

## 二。Shell Api ##

### 1. BinaryComparator 构造过滤器 ###

方式一：

hbase(main):006:0> scan 'test',{FILTER=>"RowFilter(=,'binary:row-ab')"}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
    1 row(s) in 0.0140 seconds

支持的比较运算符：= != > >= < <=，不再一一举例。

方式二：

import org.apache.hadoop.hbase.filter.CompareFilter
    import org.apache.hadoop.hbase.filter.BinaryComparator
    import org.apache.hadoop.hbase.filter.RowFilter
    
    hbase(main):016:0> scan 'test',{FILTER => RowFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), BinaryComparator.new(Bytes.toBytes('row-ab')))}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
    1 row(s) in 0.0310 seconds

支持的比较运算符：LESS、LESS\_OR\_EQUAL、EQUAL、NOT\_EQUAL、GREATER、GREATER\_OR\_EQUAL，不再一一举例。

推荐使用方式一，更简洁方便。

### 2. BinaryPrefixComparator 构造过滤器 ###

方式一：

hbase(main):023:0> scan 'test',{FILTER=>"RowFilter(=,'binaryprefix:row-ab')"}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
     row-abc                                         column=f:c4, timestamp=1588156704669, value=v4                                                                                                
    2 row(s) in 0.0360 seconds

方式二：

import org.apache.hadoop.hbase.filter.CompareFilter
    import org.apache.hadoop.hbase.filter.BinaryPrefixComparator
    import org.apache.hadoop.hbase.filter.RowFilter
    
    hbase(main):027:0> scan 'test',{FILTER => RowFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), BinaryPrefixComparator.new(Bytes.toBytes('row-ab')))}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
     row-abc                                         column=f:c4, timestamp=1588156704669, value=v4                                                                                                
    2 row(s) in 0.0110 seconds

其它同上。

### 3. SubstringComparator 构造过滤器 ###

方式一：

hbase(main):001:0> scan 'test',{FILTER=>"RowFilter(=,'substring:row-ab')"}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
     row-abc                                         column=f:c4, timestamp=1588156704669, value=v4                                                                                                
    2 row(s) in 0.3200 seconds

方式二：

import org.apache.hadoop.hbase.filter.CompareFilter
    import org.apache.hadoop.hbase.filter.SubstringComparator
    import org.apache.hadoop.hbase.filter.RowFilter
    
    hbase(main):007:0> scan 'test',{FILTER => RowFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), SubstringComparator.new('row-ab'))}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
     row-abc                                         column=f:c4, timestamp=1588156704669, value=v4                                                                                                
    2 row(s) in 0.0230 seconds

区别于上的是这里直接传入字符串进行比较，且只支持EQUAL和NOT\_EQUAL两种比较符。

### 4. RegexStringComparator 构造过滤器 ###

import org.apache.hadoop.hbase.filter.CompareFilter
    import org.apache.hadoop.hbase.filter.RegexStringComparator
    import org.apache.hadoop.hbase.filter.RowFilter
    
    hbase(main):007:0> scan 'test',{FILTER => RowFilter.new(CompareFilter::CompareOp.valueOf('EQUAL'), RegexStringComparator.new('row-ab'))}
    ROW                                              COLUMN+CELL                                                                                                                                   
     row-ab                                          column=f:c2, timestamp=1588156704669, value=v2                                                                                                
     row-abc                                         column=f:c4, timestamp=1588156704669, value=v4                                                                                                
    2 row(s) in 0.0230 seconds

该比较器直接传入字符串进行比较，且只支持EQUAL和NOT\_EQUAL两种比较符。若想使用第一种方式可以传入regexstring试一下，我的版本有点低暂时不支持，不再演示了。

注意这里的正则匹配指包含关系，对应底层find()方法。

此外，RowFilter 不支持使用LongComparator比较器，且BitComparator、NullComparator 比较器用之甚少，也不再介绍。

查看文章全部源代码请访以下GitHub地址：

https://github.com/zhoupengbo/demos-bigdata/blob/master/hbase/hbase-filters-demos/src/main/java/com/zpb/demos/RowFilterDemo.java

[HBase Filter _ Comparator]: http://mp.weixin.qq.com/s?__biz=MzUwOTE3OTYwNA==&mid=2247484249&idx=1&sn=9627e6c1ef0761c199cf563aec3e0a8f&chksm=f91760e2ce60e9f4ba9b58982c9dfa761c1574c1d4275d913aebfe22856c80356bf00e5c5699&scene=21#wechat_redirect