hbase权威指南阅读随手笔记二之过滤器

base过滤器的比较操作符：

LESS  <
LESS_OR_EQUAL <=
EQUAL =
NOT_EQUAL <>
GREATER_OR_EQUAL >=
GREATER >
NO_OP no operation

比较器：

BinaryComparator  按字节索引顺序比较指定字节数组，采用Bytes.compareTo(byte[])
BinaryPrefixComparator 跟前面相同，只是比较左端的数据是否相同
NullComparator 判断给定的是否为空
BitComparator 按位比较 a BitwiseOp class 做异或，与，并操作
RegexStringComparator 提供一个正则的比较器，仅支持 EQUAL 和非EQUAL

SubstringComparator 判断提供的子串是否出现在table的value中。

Hbase的过滤器分类

比较过滤器

1、Comparision Filters   (比较过滤器)
     1.1  RowFilter   --  行过滤器

构造函数

 public RowFilter(org.apache.hadoop.hbase.filter.CompareFilter.CompareOp rowCompareOp, org.apache.hadoop.hbase.filter.WritableByteArrayComparable rowComparator) {}

选择比较rowkey来确定选择合适的行信息。

 public class RowFilterExample {

   public static void main(String[] args) throws IOException {
     Configuration conf = HBaseConfiguration.create();

     HBaseHelper helper = HBaseHelper.getHelper(conf);
     helper.dropTable("testtable");
     helper.createTable("testtable", "colfam1", "colfam2");
     System.out.println("Adding rows to table...");
     helper.fillTable("testtable", 1, 100, 100, "colfam1", "colfam2");

     HTable table = new HTable(conf, "testtable");

     // vv RowFilterExample
     Scan scan = new Scan();
     scan.addColumn(Bytes.toBytes("colfam1"), Bytes.toBytes("col-0"));

     Filter filter1 = new RowFilter(CompareFilter.CompareOp.LESS_OR_EQUAL, // co RowFilterExample-1-Filter1 Create filter, while specifying the comparison operator and comparator. Here an exact match is needed.
       new BinaryComparator(Bytes.toBytes("row-22")));
     scan.setFilter(filter1);
     ResultScanner scanner1 = table.getScanner(scan);
     // ^^ RowFilterExample
     System.out.println("Scanning table #1...");
     // vv RowFilterExample
     for (Result res : scanner1) {
       System.out.println(res);
     }
     scanner1.close();

     Filter filter2 = new RowFilter(CompareFilter.CompareOp.EQUAL, // co RowFilterExample-2-Filter2 Another filter, this time using a regular expression to match the row keys.
       new RegexStringComparator(".*-.5"));
     scan.setFilter(filter2);
     ResultScanner scanner2 = table.getScanner(scan);
     // ^^ RowFilterExample
     System.out.println("Scanning table #2...");
     // vv RowFilterExample
     for (Result res : scanner2) {
       System.out.println(res);
     }
     scanner2.close();

     Filter filter3 = new RowFilter(CompareFilter.CompareOp.EQUAL, // co RowFilterExample-3-Filter3 The third filter uses a substring match approach.
       new SubstringComparator("-5"));
     scan.setFilter(filter3);
     ResultScanner scanner3 = table.getScanner(scan);
     // ^^ RowFilterExample
     System.out.println("Scanning table #3...");
     // vv RowFilterExample
     for (Result res : scanner3) {
       System.out.println(res);
     }
     scanner3.close();
     // ^^ RowFilterExample
   }
 }

     1.2  FamilyFilter --  列族过滤器

构造函数

 public FamilyFilter(CompareOp familyCompareOp, WritableByteArrayComparable familyComparator) {}

通过和列簇比较得到，返回结果为真的数据，示例：

 public class FamilyFilterExample {

   public static void main(String[] args) throws IOException {
     Configuration conf = HBaseConfiguration.create();

     HBaseHelper helper = HBaseHelper.getHelper(conf);
     helper.dropTable("testtable");
     helper.createTable("testtable", "colfam1", "colfam2", "colfam3", "colfam4");
     System.out.println("Adding rows to table...");
     helper.fillTable("testtable", 1, 10, 2, "colfam1", "colfam2", "colfam3", "colfam4");

     HTable table = new HTable(conf, "testtable");

     // vv FamilyFilterExample
     Filter filter1 = new FamilyFilter(CompareFilter.CompareOp.LESS, // co FamilyFilterExample-1-Filter Create filter, while specifying the comparison operator and comparator.
       new BinaryComparator(Bytes.toBytes("colfam3")));

     Scan scan = new Scan();
     scan.setFilter(filter1);
     ResultScanner scanner = table.getScanner(scan); // co FamilyFilterExample-2-Scan Scan over table while applying the filter.
     // ^^ FamilyFilterExample
     System.out.println("Scanning table... ");
     // vv FamilyFilterExample
     for (Result result : scanner) {
       System.out.println(result);
     }
     scanner.close();

     Get get1 = new Get(Bytes.toBytes("row-5"));
     get1.setFilter(filter1);
     Result result1 = table.get(get1); // co FamilyFilterExample-3-Get Get a row while applying the same filter.
     System.out.println("Result of get(): " + result1);

     Filter filter2 = new FamilyFilter(CompareFilter.CompareOp.EQUAL,
       new BinaryComparator(Bytes.toBytes("colfam3")));
     Get get2 = new Get(Bytes.toBytes("row-5")); // co FamilyFilterExample-4-Mismatch Create a filter on one column family while trying to retrieve another.
     get2.addFamily(Bytes.toBytes("colfam1"));
     get2.setFilter(filter2);
     Result result2 = table.get(get2); // co FamilyFilterExample-5-Get2 Get the same row while applying the new filter, this will return "NONE".
     System.out.println("Result of get(): " + result2);
     // ^^ FamilyFilterExample
   }
 }

     1.3 QualifierFilter --  列名过滤器

构造函数

 public QualifierFilter(CompareOp qualifierCompareOp, WritableByteArrayComparable qualifierComparator) {  }

通过和列名比较，返回为真的数据，示例：

 // vv QualifierFilterExample
    Filter filter = new QualifierFilter(CompareFilter.CompareOp.LESS_OR_EQUAL,
      new BinaryComparator(Bytes.toBytes("col-2")));

    Scan scan = new Scan();
    scan.setFilter(filter);
    ResultScanner scanner = table.getScanner(scan);
    // ^^ QualifierFilterExample
    System.out.println("Scanning table... ");
    // vv QualifierFilterExample
    for (Result result : scanner) {
      System.out.println(result);
    }
    scanner.close();

    Get get = new Get(Bytes.toBytes("row-5"));
    get.setFilter(filter);
    Result result = table.get(get);
    System.out.println("Result of get(): " + result);

     1.4 ValueFilter --  值过滤器

构造函数

 <pre name="code" class="java" style="color: rgb(88, 89, 93); font-size: 14px; line-height: 25px;">public ValueFilter(CompareOp valueCompareOp, WritableByteArrayComparable valueComparator) {}</pre>
 <pre></pre>
 通过和列名比较，返回为真的数据，示例：
 <pre></pre>
 <pre></pre>
 <pre></pre>
 <pre></pre>

 Filter filter = new ValueFilter(CompareFilter.CompareOp.EQUAL, // co ValueFilterExample-1-Filter Create filter, while specifying the comparison operator and comparator.
      new SubstringComparator(".4") );

    Scan scan = new Scan();
    scan.setFilter(filter); // co ValueFilterExample-2-SetFilter Set filter for the scan.
    ResultScanner scanner = table.getScanner(scan);
    // ^^ ValueFilterExample
    System.out.println("Results of scan:");
    // vv ValueFilterExample
    for (Result result : scanner) {
      for (KeyValue kv : result.raw()) {
        System.out.println("KV: " + kv + ", Value: " + // co ValueFilterExample-3-Print1 Print out value to check that filter works.
          Bytes.toString(kv.getValue()));
      }
    }
    scanner.close();

    Get get = new Get(Bytes.toBytes("row-5"));
    get.setFilter(filter); // co ValueFilterExample-4-SetFilter2 Assign same filter to Get instance.
    Result result = table.get(get);
    // ^^ ValueFilterExample
    System.out.println("Result of get: ");
    // vv ValueFilterExample
    for (KeyValue kv : result.raw()) {
      System.out.println("KV: " + kv + ", Value: " +
        Bytes.toString(kv.getValue()));
    }

     1.5 DependentColumnFilter  --  参考过滤器

该过滤器有两个参数 —— 列族和列修饰。 尝试找到该列所在的每一行，并返回该行具有相同时间戳的全部键值对。如果某一行不包含指定的列，则该行的任何键值对都不返回。
该过滤器还可以有一个可选布尔参数 —— dropDependentColumn. 如果为true, 从属的列不返回。
该过滤器还可以有两个可选参数 —— 一个比较操作符和一个值比较器，用于列族和修饰的进一步检查。如果从属的列找到，其值还必须通过值检查，然后就是时间戳必须考虑。

 package filters;

 // cc DependentColumnFilterExample Example using a filter to include only specific column families
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.client.Get;
 import org.apache.hadoop.hbase.client.HTable;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.hbase.client.ResultScanner;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.filter.BinaryPrefixComparator;
 import org.apache.hadoop.hbase.filter.CompareFilter;
 import org.apache.hadoop.hbase.filter.DependentColumnFilter;
 import org.apache.hadoop.hbase.filter.Filter;
 import org.apache.hadoop.hbase.filter.RegexStringComparator;
 import org.apache.hadoop.hbase.filter.WritableByteArrayComparable;
 import org.apache.hadoop.hbase.util.Bytes;
 import util.HBaseHelper;

 import java.io.IOException;

 public class DependentColumnFilterExample {

   private static HTable table = null;

   // vv DependentColumnFilterExample
   private static void filter(boolean drop,
       CompareFilter.CompareOp operator,
       WritableByteArrayComparable comparator)
   throws IOException {
     Filter filter;
     if (comparator != null) {
       filter = new DependentColumnFilter(Bytes.toBytes("colfam1"), // co DependentColumnFilterExample-1-CreateFilter Create the filter with various options.
         Bytes.toBytes("col-5"), drop, operator, comparator);
     } else {
       filter = new DependentColumnFilter(Bytes.toBytes("colfam1"),
         Bytes.toBytes("col-5"), drop);

     }

     Scan scan = new Scan();
     scan.setFilter(filter);
     ResultScanner scanner = table.getScanner(scan);
     // ^^ DependentColumnFilterExample
     System.out.println("Results of scan:");
     // vv DependentColumnFilterExample
     for (Result result : scanner) {
       for (KeyValue kv : result.raw()) {
         System.out.println("KV: " + kv + ", Value: " +
           Bytes.toString(kv.getValue()));
       }
     }
     scanner.close();

     Get get = new Get(Bytes.toBytes("row-5"));
     get.setFilter(filter);
     Result result = table.get(get);
     // ^^ DependentColumnFilterExample
     System.out.println("Result of get: ");
     // vv DependentColumnFilterExample
     for (KeyValue kv : result.raw()) {
       System.out.println("KV: " + kv + ", Value: " +
         Bytes.toString(kv.getValue()));
     }
     // ^^ DependentColumnFilterExample
     System.out.println("");
     // vv DependentColumnFilterExample
   }

   public static void main(String[] args) throws IOException {
     // ^^ DependentColumnFilterExample
     Configuration conf = HBaseConfiguration.create();

     HBaseHelper helper = HBaseHelper.getHelper(conf);
     helper.dropTable("testtable");
     helper.createTable("testtable", "colfam1", "colfam2");
     System.out.println("Adding rows to table...");
     helper.fillTable("testtable", 1, 10, 10, true, "colfam1", "colfam2");

     table = new HTable(conf, "testtable");

     // vv DependentColumnFilterExample
     filter(true, CompareFilter.CompareOp.NO_OP, null);
     filter(false, CompareFilter.CompareOp.NO_OP, null); // co DependentColumnFilterExample-2-Filter Call filter method with various options.
     filter(true, CompareFilter.CompareOp.EQUAL,
       new BinaryPrefixComparator(Bytes.toBytes("val-5")));
     filter(false, CompareFilter.CompareOp.EQUAL,
       new BinaryPrefixComparator(Bytes.toBytes("val-5")));
     filter(true, CompareFilter.CompareOp.EQUAL,
       new RegexStringComparator(".*\\.5"));
     filter(false, CompareFilter.CompareOp.EQUAL,
       new RegexStringComparator(".*\\.5"));
   }
   // ^^ DependentColumnFilterExample}

2、Dedicated Filters --  专用过滤器
     2.1 SingleColumnValueFilter --  单列值过滤器 

选定列簇和某一列，然后与列的value相比，正确的返回全部的row，注意如果某一行不含有该列，同样返回，除非通过filterIfColumnMissing 设置成真。

构造函数

 <pre name="code" class="java">SingleColumnValueFilter(byte[] family, byte[] qualifier, CompareOp compareOp, byte[] value)
 SingleColumnValueFilter(byte[] family, byte[] qualifier, CompareOp compareOp, WritableByteArrayComparable comparator)</pre>
 <pre></pre>
 第一个构造函数相当于构建了一个BinaryComparator的实例。其他的跟CompareFilter的参数含义一样。
 <pre></pre>
 <pre></pre>
 <pre></pre>

该过滤器通过下面两个参数 filterIfMissing,latestVersionOnly

 boolean getFilterIfMissing()
 void setFilterIfMissing(boolean filterIfMissing)
 boolean getLatestVersionOnly()
 void setLatestVersionOnly(boolean latestVersionOnly)

如果 filterIfColumnMissing 标志设为真，如果该行没有指定的列，那么该行的所有列将不发出。缺省值为假。
如果setLatestVersionOnly 标志设为假，将检查此前的版本。缺省值为真。实例如下：

 // vv SingleColumnValueFilterExample
   SingleColumnValueFilter filter = new SingleColumnValueFilter(
     Bytes.toBytes("colfam1"),
     Bytes.toBytes("col-5"),
     CompareFilter.CompareOp.NOT_EQUAL,
     new SubstringComparator("val-5"));
   filter.setFilterIfMissing(true);

   Scan scan = new Scan();
   scan.setFilter(filter);
   ResultScanner scanner = table.getScanner(scan);
   // ^^ SingleColumnValueFilterExample
   System.out.println("Results of scan:");
   // vv SingleColumnValueFilterExample
   for (Result result : scanner) {
     for (KeyValue kv : result.raw()) {
       System.out.println("KV: " + kv + ", Value: " +
         Bytes.toString(kv.getValue()));
     }
   }
   scanner.close();

   Get get = new Get(Bytes.toBytes("row-6"));
   get.setFilter(filter);
   Result result = table.get(get);
   System.out.println("Result of get: ");
   for (KeyValue kv : result.raw()) {
     System.out.println("KV: " + kv + ", Value: " +
       Bytes.toString(kv.getValue()));
   }

     2.2 SingleColumnValueExcludeFilter --  单列排除过滤器

该过滤器同上面的过滤器正好相反，如果条件相符，将不会返回该列的内容。

     2.3 PrefixFilter --  前缀过滤器

所有的row的实例匹配prefix的时候返回结果集合

 Filter filter = new PrefixFilter(Bytes.toBytes("row1"));
 Scan scan = new Scan();
 scan.setFilter(filter);
 ResultScanner scanner = table.getScanner(scan);


 for(Result result: scanner){
     for(KeyValue kv: result.raw()) {
         System.out.println("KV:" + kv + ", Value:"  + Bytes.toString(kv.getValue()));
     }
 }
 scanner.close();


 Get get = new Get(Bytes.toBytes("row-5"));
 get.setFilter(filter);
 Result result = table.get(get);
 for(KeyValue kv : result.raw()){
     System.out.println("KV:" + kv + ", Value:"  + Bytes.toString(kv.getValue()));
 }

     2.4 PageFilter --  分页过滤器

页过滤，通过设置pagesize参数可以返回每一页page的数量。

客户端需要记住上一次访问的row的key值。

 package hbaseTest;

 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.client.HTable;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.hbase.client.ResultScanner;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.filter.Filter;
 import org.apache.hadoop.hbase.filter.PageFilter;
 import org.apache.hadoop.hbase.util.Bytes;

 import java.io.IOException;

 /**
  * Hello world!
  */
 public class PageFilterExample {
     public static void main(String[] args) throws IOException {
         Configuration config = HBaseConfiguration.create();
         config.set("hbase.zookeeper.quorum", "QT-H-0038");

         String tableName = "testTable";
         String cfName = "colfam1";
         final byte[] POSTFIX = new byte[] { 0x00 };
         HTable table = new HTable(config, tableName);
         Filter filter = new PageFilter(15);
         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，不然死循环了
                 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);
     }

 }

因为hbase的row是字典序列排列的，因此上一次的lastrow需要添加额外的0表示新的开始。另外startKey的那一行是包含在scan里面的。

     2.5 KeyOnlyFilter --  行键过滤器

因为一些应用只想获取data数据，而不是真实的val，可以使用这个过滤器。该过滤器通过

 KeyOnlyFilter(boolean lenAsVal)

lenAsVal默认为假，表示不把val的长度作为val。否则 val的长度将作为val输出。

         final byte[] POSTFIX = new byte[] { 0x00 };
         HTable table = new HTable(config, tableName);
         Filter filter = new KeyOnlyFilter(false);
         byte[] lastRow = null;
         int totalRows = 0;


         Scan scan = new Scan();
         scan.setFilter(filter);
         ResultScanner scanner = table.getScanner(scan);
         for(Result result: scanner){
             for(KeyValue kv: result.raw()){
                 System.out.println(kv + ":" + Bytes.toString(kv.getValue()));
             }
         }

     2.6 FirstKeyOnlyFilter --  首次行键过滤器

在对hbase的表进行扫描的时候，如果指定了FirstKeyOnlyFilter过滤条件则仅仅会返回相同key的第一条kv。
当对hbase中的表进行count，sum操作等集合操作的时候，使用FirstKeyOnlyFilter会带来性能上的提升。

 public class KeyOnlyFilterExample {
     public static void main(String[] args) throws IOException {
         Configuration config = HBaseConfiguration.create();
         config.set("hbase.zookeeper.quorum", "QT-H-0038");

         String tableName = "testTable";
         String cfName = "colfam1";
         final byte[] POSTFIX = new byte[] { 0x00 };
         HTable table = new HTable(config, tableName);
         Filter filter = new FirstKeyOnlyFilter();
         byte[] lastRow = null;
         int totalRows = 0;

         Scan scan = new Scan();
         scan.setFilter(filter);
         ResultScanner scanner = table.getScanner(scan);
         for(Result result: scanner){
             for(KeyValue kv: result.raw()){
                 System.out.println(kv + ":" + Bytes.toString(kv.getValue()));
             }
         }
     }
 }

返回的结果是

 row-5/colfam1:qual1/1354673733503/Put/vlen=4:row1
 row1/colfam1:qual1/1354432930568/Put/vlen=4:val1
 row2/colfam1:qual2/1354432930568/Put/vlen=4:val3

如果注释掉过滤器的返回的结果是：

 row-5/colfam1:qual1/1354673733503/Put/vlen=4:row1
 row1/colfam1:qual1/1354432930568/Put/vlen=4:val1
 row1/colfam1:qual2/1354435819120/Put/vlen=4:val2
 row2/colfam1:qual2/1354432930568/Put/vlen=4:val3

     2.7 InclusiveStopFilter --  包含结束的过滤器

因为hbase的scan包含start-row不包含stop-row 如果使用这个过滤器我们可以包含stop-row

 HTable table = new HTable(config, tableName);

 Filter filter  = new InclusiveStopFilter(Bytes.toBytes("row1"));

 Scan scan = new Scan();
 scan.setFilter(filter);
 scan.setStartRow(Bytes.toBytes("row-5"));
 ResultScanner scanner = table.getScanner(scan);

 for(Result result: scanner){
     System.out.println(result);
 }

会看到row1包含在结果中了。

     2.8 TimestampsFilter --  时间戳过滤器

当访问某个Timestamp的新闻的时候，我们需要如下的代码：

 TimestampsFilter(List<Long> timestamps)

接受的参数的list参数，该Filter也可以和scan.setTimeRange混合使用。例如：

 // vv TimestampFilterExample
     List<Long> ts = new ArrayList<Long>();
     ts.add(new Long(5));
     ts.add(new Long(10)); // co TimestampFilterExample-1-AddTS Add timestamps to the list.
     ts.add(new Long(15));
     Filter filter = new TimestampsFilter(ts);

     Scan scan1 = new Scan();
     scan1.setFilter(filter); // co TimestampFilterExample-2-AddFilter Add the filter to an otherwise default Scan instance.
     ResultScanner scanner1 = table.getScanner(scan1);
     // ^^ TimestampFilterExample
     System.out.println("Results of scan #1:");
     // vv TimestampFilterExample
     for (Result result : scanner1) {
       System.out.println(result);
     }
     scanner1.close();

     Scan scan2 = new Scan();
     scan2.setFilter(filter);
     scan2.setTimeRange(8, 12); // co TimestampFilterExample-3-AddTSRange Also add a time range to verify how it affects the filter
     ResultScanner scanner2 = table.getScanner(scan2);
     // ^^ TimestampFilterExample
     System.out.println("Results of scan #2:");
     // vv TimestampFilterExample
     for (Result result : scanner2) {
       System.out.println(result);
     }
     scanner2.close();

     2.9  ColumnCountGetFilter --  列计数过滤器

这个在scan时，无用。

     2.10 ColumnPaginationFilter（下来用到的时候在仔细研究下） --  列分页过滤器

 * A filter, based on the ColumnCountGetFilter, takes two arguments: limit and offset.
 * This filter can be used for row-based indexing, where references to other tables are stored across many columns,
 * in order to efficient lookups and paginated results for end users.

 

 Filter filter = new ColumnPaginationFilter(5, 15);

    Scan scan = new Scan();
    scan.setFilter(filter);
    ResultScanner scanner = table.getScanner(scan);
    // ^^ ColumnPaginationFilterExample
    System.out.println("Results of scan:");
    // vv ColumnPaginationFilterExample
    for (Result result : scanner) {
      System.out.println(result);
    }
    scanner.close();

     2.11 ColumnPrefixFilter --  列前缀过滤器

跟prefxiFilter相似，只是改成了Column，实例如下：

 // vv ColumnPaginationFilterExample
       Filter filter = new ColumnPrefixFilter(Bytes.toBytes("qual2"));

       Scan scan = new Scan();
       scan.setFilter(filter);
       ResultScanner scanner = table.getScanner(scan);
       // ^^ ColumnPaginationFilterExample
       System.out.println("Results of scan:");
       // vv ColumnPaginationFilterExample
       for (Result result : scanner) {
           System.out.println(result);
       }
       scanner.close();

值scan到与列值与前面匹配的数据。例如qual2匹配qual21。

 

     2.12 RandomRowFilter --  随机行过滤器

随即的返回row的数据，构造函数为

 RandomRowFilter(float chance)

chance取值为0到1.0，如果<0则为空，如果>1则包含所有的行。

3、Decorating Filters （附加过滤器）

装饰性过滤器

     3.1  SkipFilter --  跳转过滤器

这个过滤器只作用到keyValueFilter上。KeyValueFilter会返回所有满足条件的row及对应的列。

而加上SkipFilter以后。会发现如果某一行的某一列不符合条件，则这一行全部不返回了。

 public static void main(String[] args) throws IOException {
    Configuration conf = HBaseConfiguration.create();

    HBaseHelper helper = HBaseHelper.getHelper(conf);
    helper.dropTable("testtable");
    helper.createTable("testtable", "colfam1");
    System.out.println("Adding rows to table...");
    helper.fillTable("testtable", 1, 30, 5, 2, true, true, "colfam1");

    HTable table = new HTable(conf, "testtable");

    // vv SkipFilterExample
    Filter filter1 = new ValueFilter(CompareFilter.CompareOp.NOT_EQUAL,
      new BinaryComparator(Bytes.toBytes("val-0")));

    Scan scan = new Scan();
    scan.setFilter(filter1); // co SkipFilterExample-1-AddFilter1 Only add the ValueFilter to the first scan.
    ResultScanner scanner1 = table.getScanner(scan);
    // ^^ SkipFilterExample
    System.out.println("Results of scan #1:");
    int n = 0;
    // vv SkipFilterExample
    for (Result result : scanner1) {
      for (KeyValue kv : result.raw()) {
        System.out.println("KV: " + kv + ", Value: " +
          Bytes.toString(kv.getValue()));
        // ^^ SkipFilterExample
        n++;
        // vv SkipFilterExample
      }
    }
    scanner1.close();

    Filter filter2 = new SkipFilter(filter1);

    scan.setFilter(filter2); // co SkipFilterExample-2-AddFilter2 Add the decorating skip filter for the second scan.
    ResultScanner scanner2 = table.getScanner(scan);
    // ^^ SkipFilterExample
    System.out.println("Total KeyValue count for scan #1: " + n);
    n = 0;
    System.out.println("Results of scan #2:");
    // vv SkipFilterExample
    for (Result result : scanner2) {
      for (KeyValue kv : result.raw()) {
        System.out.println("KV: " + kv + ", Value: " +
          Bytes.toString(kv.getValue()));
        // ^^ SkipFilterExample
        n++;
        // vv SkipFilterExample
      }
    }
    scanner2.close();
    // ^^ SkipFilterExample
    System.out.println("Total KeyValue count for scan #2: " + n);
  }

     3.2 WhileMatchFilters --  全匹配过滤器

相当于while执行，知道不match就break了返回了。

转自：http://blog.csdn.net/saint1126/article/details/8257941

红字是自己加的标记。