HBaseFilter过滤器之ValueFilter详解

database

前言:本文详细介绍了 HBase ValueFilter 过滤器 Java&Shell API 的使用,并贴出了相关示例代码以供参考。ValueFilter 基于列值进行过滤,在工作中涉及到需要通过HBase 列值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

一。Java Api

头部代码

/**

* 用于列值过滤。

*/

public class ValueFilterDemo {

private static boolean isok = false;

private static String tableName = "test";

private static String[] cfs = new String[]{"f1","f2"};

private static String[] data = new String[]{

"row-1:f1:c1:abcdefg",

"row-2:f1:c2:abc",

"row-3:f2:c3:abc123456",

"row-4:f2:c4:1234abc567"

};

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);

// 造数据

myBase.putRows(connection, tableName, data);

}

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

        ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes("abc"))); // [row-2:f1:c2:abc]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.NOT_EQUAL, new BinaryComparator(Bytes.toBytes("abc"))); // [row-1:f1:c1:abcdefg, row-3:f2:c3:abc123456, row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.GREATER, new BinaryComparator(Bytes.toBytes("abc"))); // [row-1:f1:c1:abcdefg, row-3:f2:c3:abc123456]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.GREATER_OR_EQUAL, new BinaryComparator(Bytes.toBytes("abc1"))); // [row-1:f1:c1:abcdefg, row-3:f2:c3:abc123456]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.LESS, new BinaryComparator(Bytes.toBytes("abc"))); // [row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryComparator(Bytes.toBytes("abc"))); // [row-2:f1:c2:abc, row-4:f2:c4:1234abc567]

2. BinaryPrefixComparator 构造过滤器

        ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes("123"))); // [row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.NOT_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("ab"))); // [row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.GREATER, new BinaryPrefixComparator(Bytes.toBytes("ab"))); // [] 只比较prefix长度的字节

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.GREATER_OR_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("ab"))); // [row-1:f1:c1:abcdefg, row-2:f1:c2:abc, row-3:f2:c3:abc123456]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.LESS, new BinaryPrefixComparator(Bytes.toBytes("abc"))); // [row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryPrefixComparator(Bytes.toBytes("abc"))); // [row-1:f1:c1:abcdefg, row-2:f1:c2:abc, row-3:f2:c3:abc123456, row-4:f2:c4:1234abc567]

3. SubstringComparator 构造过滤器

        ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.EQUAL, new SubstringComparator("123")); // [row-3:f2:c3:abc123456, row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.NOT_EQUAL, new SubstringComparator("def")); // [row-2:f1:c2:abc, row-3:f2:c3:abc123456, row-4:f2:c4:1234abc567]```

4. RegexStringComparator 构造过滤器

        ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.NOT_EQUAL, new RegexStringComparator("4[a-z]")); // [row-1:f1:c1:abcdefg, row-2:f1:c2:abc, row-3:f2:c3:abc123456]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator("4[a-z]")); // [row-4:f2:c4:1234abc567]

ValueFilter valueFilter = new ValueFilter(CompareFilter.CompareOp.EQUAL, new RegexStringComparator("abc")); // [row-1:f1:c1:abcdefg, row-2:f1:c2:abc, row-3:f2:c3:abc123456, row-4:f2:c4:1234abc567]

尾部代码

		scan.setFilter(valueFilter);

ResultScanner scanner = table.getScanner(scan);

Iterator<Result> iterator = scanner.iterator();

LinkedList<String> keys = new LinkedList<>();

while (iterator.hasNext()) {

String key = "";

Result result = iterator.next();

for (Cell cell : result.rawCells()) {

byte[] rowkey = CellUtil.cloneRow(cell);

byte[] family = CellUtil.cloneFamily(cell);

byte[] column = CellUtil.cloneQualifier(cell);

byte[] value = CellUtil.cloneValue(cell);

key = Bytes.toString(rowkey) + ":" + Bytes.toString(family) + ":" + Bytes.toString(column) + ":" + Bytes.toString(value);

keys.add(key);

}

}

System.out.println(keys);

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=>"ValueFilter(=,"binary:abc")"}

ROW COLUMN+CELL

row-2 column=f1:c2, timestamp=1589453592471, value=abc

1 row(s) in 0.0240 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.ValueFilter

hbase(main):010:0> scan "test",{FILTER => ValueFilter.new(CompareFilter::CompareOp.valueOf("EQUAL"), BinaryComparator.new(Bytes.toBytes("abc")))}

ROW COLUMN+CELL

row-2 column=f1:c2, timestamp=1589453592471, value=abc

1 row(s) in 0.0230 seconds

支持的比较运算符:LESSLESS_OR_EQUALEQUALNOT_EQUALGREATERGREATER_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):011:0> scan "test",{FILTER=>"ValueFilter(=,"binaryprefix:ab")"}

ROW COLUMN+CELL

row-1 column=f1:c1, timestamp=1589453592471, value=abcdefg

row-2 column=f1:c2, timestamp=1589453592471, value=abc

row-3 column=f2:c3, timestamp=1589453592471, value=abc123456

3 row(s) in 0.0430 seconds

方式二:

import org.apache.hadoop.hbase.filter.CompareFilter

import org.apache.hadoop.hbase.filter.BinaryPrefixComparator

import org.apache.hadoop.hbase.filter.ValueFilter

hbase(main):013:0> scan "test",{FILTER => ValueFilter.new(CompareFilter::CompareOp.valueOf("EQUAL"), BinaryPrefixComparator.new(Bytes.toBytes("ab")))}

ROW COLUMN+CELL

row-1 column=f1:c1, timestamp=1589453592471, value=abcdefg

row-2 column=f1:c2, timestamp=1589453592471, value=abc

row-3 column=f2:c3, timestamp=1589453592471, value=abc123456

3 row(s) in 0.0440 seconds

其它同上。

3. SubstringComparator 构造过滤器

方式一:

hbase(main):014:0> scan "test",{FILTER=>"ValueFilter(=,"substring:123")"}

ROW COLUMN+CELL

row-3 column=f2:c3, timestamp=1589453592471, value=abc123456

row-4 column=f2:c4, timestamp=1589453592471, value=1234abc567

2 row(s) in 0.0340 seconds

方式二:

import org.apache.hadoop.hbase.filter.CompareFilter

import org.apache.hadoop.hbase.filter.SubstringComparator

import org.apache.hadoop.hbase.filter.ValueFilter

hbase(main):016:0> scan "test",{FILTER => ValueFilter.new(CompareFilter::CompareOp.valueOf("EQUAL"), SubstringComparator.new("123"))}

ROW COLUMN+CELL

row-3 column=f2:c3, timestamp=1589453592471, value=abc123456

row-4 column=f2:c4, timestamp=1589453592471, value=1234abc567

2 row(s) in 0.0240 seconds

区别于上的是这里直接传入字符串进行比较,且只支持EQUALNOT_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.ValueFilter

hbase(main):018:0> scan "test",{FILTER => ValueFilter.new(CompareFilter::CompareOp.valueOf("EQUAL"), RegexStringComparator.new("4[a-z]"))}

ROW COLUMN+CELL

row-4 column=f2:c4, timestamp=1589453592471, value=1234abc567

1 row(s) in 0.0290 seconds

该比较器直接传入字符串进行比较,且只支持EQUALNOT_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。

ValueFilter 不支持使用 LongComparator 比较器,且 BitComparatorNullComparator 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/ValueFilterDemo.java

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