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1   /*
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  
20  package org.apache.hadoop.hbase.filter;
21  
22  import java.util.ArrayList;
23  
24  import org.apache.hadoop.hbase.util.ByteStringer;
25  import org.apache.hadoop.hbase.classification.InterfaceAudience;
26  import org.apache.hadoop.hbase.classification.InterfaceStability;
27  import org.apache.hadoop.hbase.Cell;
28  import org.apache.hadoop.hbase.exceptions.DeserializationException;
29  import org.apache.hadoop.hbase.protobuf.generated.FilterProtos;
30  import org.apache.hadoop.hbase.util.Bytes;
31  
32  import com.google.common.base.Preconditions;
33  import com.google.protobuf.InvalidProtocolBufferException;
34  
35  /**
36   * A Filter that stops after the given row.  There is no "RowStopFilter" because
37   * the Scan spec allows you to specify a stop row.
38   *
39   * Use this filter to include the stop row, eg: [A,Z].
40   */
41  @InterfaceAudience.Public
42  @InterfaceStability.Stable
43  public class InclusiveStopFilter extends FilterBase {
44    private byte [] stopRowKey;
45    private boolean done = false;
46  
47    public InclusiveStopFilter(final byte [] stopRowKey) {
48      this.stopRowKey = stopRowKey;
49    }
50  
51    public byte[] getStopRowKey() {
52      return this.stopRowKey;
53    }
54  
55    @Override
56    public ReturnCode filterKeyValue(Cell v) {
57      if (done) return ReturnCode.NEXT_ROW;
58      return ReturnCode.INCLUDE;
59    }
60  
61    public boolean filterRowKey(byte[] buffer, int offset, int length) {
62      if (buffer == null) {
63        //noinspection RedundantIfStatement
64        if (this.stopRowKey == null) {
65          return true; //filter...
66        }
67        return false;
68      }
69      // if stopRowKey is <= buffer, then true, filter row.
70      int cmp = Bytes.compareTo(stopRowKey, 0, stopRowKey.length,
71        buffer, offset, length);
72  
73      done = reversed ? cmp > 0 : cmp < 0;
74      return done;
75    }
76  
77    public boolean filterAllRemaining() {
78      return done;
79    }
80  
81    public static Filter createFilterFromArguments (ArrayList<byte []> filterArguments) {
82      Preconditions.checkArgument(filterArguments.size() == 1,
83                                  "Expected 1 but got: %s", filterArguments.size());
84      byte [] stopRowKey = ParseFilter.removeQuotesFromByteArray(filterArguments.get(0));
85      return new InclusiveStopFilter(stopRowKey);
86    }
87  
88    /**
89     * @return The filter serialized using pb
90     */
91    public byte [] toByteArray() {
92      FilterProtos.InclusiveStopFilter.Builder builder =
93        FilterProtos.InclusiveStopFilter.newBuilder();
94      if (this.stopRowKey != null) builder.setStopRowKey(ByteStringer.wrap(this.stopRowKey));
95      return builder.build().toByteArray();
96    }
97  
98    /**
99     * @param pbBytes A pb serialized {@link InclusiveStopFilter} instance
100    * @return An instance of {@link InclusiveStopFilter} made from <code>bytes</code>
101    * @throws DeserializationException
102    * @see #toByteArray
103    */
104   public static InclusiveStopFilter parseFrom(final byte [] pbBytes)
105   throws DeserializationException {
106     FilterProtos.InclusiveStopFilter proto;
107     try {
108       proto = FilterProtos.InclusiveStopFilter.parseFrom(pbBytes);
109     } catch (InvalidProtocolBufferException e) {
110       throw new DeserializationException(e);
111     }
112     return new InclusiveStopFilter(proto.hasStopRowKey()?proto.getStopRowKey().toByteArray():null);
113   }
114 
115   /**
116    * @param other
117    * @return true if and only if the fields of the filter that are serialized
118    * are equal to the corresponding fields in other.  Used for testing.
119    */
120   boolean areSerializedFieldsEqual(Filter o) {
121     if (o == this) return true;
122     if (!(o instanceof InclusiveStopFilter)) return false;
123 
124     InclusiveStopFilter other = (InclusiveStopFilter)o;
125     return Bytes.equals(this.getStopRowKey(), other.getStopRowKey());
126   }
127 
128   @Override
129   public String toString() {
130     return this.getClass().getSimpleName() + " " + Bytes.toStringBinary(this.stopRowKey);
131   }
132 }