[Hbase]Hbase的过滤器分类-蒲公英云

Hbase的过滤器分类

1、比较过滤器

1.1、行键过滤器RowFilter

Filter filter1 = new RowFilter(CompareOp.LESS_OR_EQUAL, new BinaryComparator(Bytes.toBytes("row-22")));  
scan.setFilter(filter1);

1.2、列族过滤器FamilyFilter

Filter filter1 = new FamilyFilter(CompareFilter.CompareOp.LESS, new BinaryComparator(Bytes.toBytes("colfam3")));
scan.setFilter(filter1);

1.3、列过滤器QualifierFilter

filter = new QualifierFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, new BinaryComparator(Bytes.toBytes("col-2")));
scan.setFilter(filter1);

1.4、值过滤器ValueFilter

Filter filter = new ValueFilter(CompareFilter.CompareOp.EQUAL, new SubstringComparator(".4") );  
scan.setFilter(filter1);

2、专用过滤器

2.1、单列值过滤器SingleColumnValueFilter

返回满足条件的整行

SingleColumnValueFilter filter = new SingleColumnValueFilter(  
    Bytes.toBytes("colfam1"),  
    Bytes.toBytes("col-5"),  
    CompareFilter.CompareOp.NOT_EQUAL,  
    new SubstringComparator("val-5"));  
filter.setFilterIfMissing(true);  //如果不设置为true，则那些不包含指定column的行也会返回
scan.setFilter(filter1);

2.2、SingleColumnValueExcludeFilter与SingleColumnValueFilter相反

2.3、前缀过滤器PrefixFilter

针对行键

Filter filter = new PrefixFilter(Bytes.toBytes("row1"));  
scan.setFilter(filter1);

2.4、列前缀过滤器ColumnPrefixFilter

Filter filter = new ColumnPrefixFilter(Bytes.toBytes("qual2"));  
scan.setFilter(filter1);

2.5、分页过滤器PageFilter

public static void main(String[] args) throws Exception {
        Configuration conf = HBaseConfiguration.create();
        conf.set("hbase.zookeeper.quorum", "spark01:2181,spark02:2181,spark03:2181");
        String tableName = "testfilter";  
        String cfName = "f1";  
        final byte[] POSTFIX = new byte[] { 0x00 };  
        HTable table = new HTable(conf, tableName);  
        Filter filter = new PageFilter(3);  
        byte[] lastRow = null;  
        int totalRows = 0;  
        while (true) {  
            Scan scan = new Scan();  
            scan.setFilter(filter);  
            if(lastRow != null){  
                //注意这里添加了POSTFIX操作，用来重置扫描边界  
                byte[] startRow = Bytes.add(lastRow,POSTFIX);  
                scan.setStartRow(startRow);  
            }  
            ResultScanner scanner = table.getScanner(scan);  
            int localRows = 0;  
            Result result;  
            while((result = scanner.next()) != null){  
                System.out.println(localRows++ + ":" + result);  
                totalRows ++;  
                lastRow = result.getRow();  
            }  
            scanner.close();  
            if(localRows == 0) break;  
        }  
        System.out.println("total rows:" + totalRows);  
    }

3、多种过滤条件使用

/**
     * 多种过滤条件的使用方法
     * @throws Exception
     */
    @Test
    public void testScan() throws Exception{
        HTable table = new HTable(conf, "person_info".getBytes());
        Scan scan = new Scan(Bytes.toBytes("person_rk_bj_zhang_000001"), Bytes.toBytes("person_rk_bj_zhang_000002"));
        //前缀过滤器----针对行键
        Filter filter = new PrefixFilter(Bytes.toBytes("rk"));
        //行过滤器  ---针对行键
        ByteArrayComparable rowComparator = new BinaryComparator(Bytes.toBytes("person_rk_bj_zhang_000001"));
        RowFilter rf = new RowFilter(CompareOp.LESS_OR_EQUAL, rowComparator);
        /**
         * 假设rowkey格式为：创建日期_发布日期_ID_TITLE
         * 目标：查找  发布日期  为  2014-12-21  的数据
         */
        rf = new RowFilter(CompareOp.EQUAL , new SubstringComparator("_2014-12-21_"));
        //单值过滤器1完整匹配字节数组
        new SingleColumnValueFilter("base_info".getBytes(), "name".getBytes(), CompareOp.EQUAL, "zhangsan".getBytes());
        //单值过滤器2 匹配正则表达式
        ByteArrayComparable comparator = new RegexStringComparator("zhang.");
        new SingleColumnValueFilter("info".getBytes(), "NAME".getBytes(), CompareOp.EQUAL, comparator);
        //单值过滤器3匹配是否包含子串,大小写不敏感
        comparator = new SubstringComparator("wu");
        new SingleColumnValueFilter("info".getBytes(), "NAME".getBytes(), CompareOp.EQUAL, comparator);
        //键值对元数据过滤-----family过滤----字节数组完整匹配
        FamilyFilter ff = new FamilyFilter(
                CompareOp.EQUAL , 
                new BinaryComparator(Bytes.toBytes("base_info"))   //表中不存在inf列族，过滤结果为空
                );
        //键值对元数据过滤-----family过滤----字节数组前缀匹配
        ff = new FamilyFilter(
                CompareOp.EQUAL , 
                new BinaryPrefixComparator(Bytes.toBytes("inf"))   //表中存在以inf打头的列族info，过滤结果为该列族所有行
                );
       //键值对元数据过滤-----qualifier过滤----字节数组完整匹配
        filter = new QualifierFilter(
                CompareOp.EQUAL , 
                new BinaryComparator(Bytes.toBytes("na"))   //表中不存在na列，过滤结果为空
                );
        filter = new QualifierFilter(
                CompareOp.EQUAL , 
                new BinaryPrefixComparator(Bytes.toBytes("na"))   //表中存在以na打头的列name，过滤结果为所有行的该列数据
                );
        //基于列名(即Qualifier)前缀过滤数据的ColumnPrefixFilter
        filter = new ColumnPrefixFilter("na".getBytes());
        //基于列名(即Qualifier)多个前缀过滤数据的MultipleColumnPrefixFilter
        byte[][] prefixes = new byte[][] {Bytes.toBytes("na"), Bytes.toBytes("me")};
        filter = new MultipleColumnPrefixFilter(prefixes);
        //为查询设置过滤条件
        scan.setFilter(filter);
        scan.addFamily(Bytes.toBytes("base_info"));
        //一行
//      Result result = table.get(get);
        //多行的数据
        ResultScanner scanner = table.getScanner(scan);
        for(Result r : scanner){
            /**
            for(KeyValue kv : r.list()){
                String family = new String(kv.getFamily());
                System.out.println(family);
                String qualifier = new String(kv.getQualifier());
                System.out.println(qualifier);
                System.out.println(new String(kv.getValue()));
            }
            */
            //直接从result中取到某个特定的value
            byte[] value = r.getValue(Bytes.toBytes("base_info"), Bytes.toBytes("name"));
            System.out.println(new String(value));
        }
        table.close();
    }