001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.filter;
019
020import java.io.IOException;
021import java.util.ArrayList;
022import org.apache.hadoop.hbase.Cell;
023import org.apache.hadoop.hbase.CompareOperator;
024import org.apache.hadoop.hbase.exceptions.DeserializationException;
025import org.apache.yetus.audience.InterfaceAudience;
026
027import org.apache.hbase.thirdparty.com.google.protobuf.InvalidProtocolBufferException;
028
029import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
030import org.apache.hadoop.hbase.shaded.protobuf.generated.FilterProtos;
031
032/**
033 * This filter is used to filter based on the column qualifier. It takes an operator (equal,
034 * greater, not equal, etc) and a byte [] comparator for the column qualifier portion of a key.
035 * <p>
036 * This filter can be wrapped with {@link WhileMatchFilter} and {@link SkipFilter} to add more
037 * control.
038 * <p>
039 * Multiple filters can be combined using {@link FilterList}.
040 * <p>
041 * If an already known column qualifier is looked for, use
042 * {@link org.apache.hadoop.hbase.client.Get#addColumn} directly rather than a filter.
043 */
044@InterfaceAudience.Public
045public class QualifierFilter extends CompareFilter {
046  /**
047   * Constructor.
048   * @param op                  the compare op for column qualifier matching
049   * @param qualifierComparator the comparator for column qualifier matching
050   */
051  public QualifierFilter(final CompareOperator op, final ByteArrayComparable qualifierComparator) {
052    super(op, qualifierComparator);
053  }
054
055  @Override
056  public ReturnCode filterCell(final Cell c) {
057    if (compareQualifier(getCompareOperator(), this.comparator, c)) {
058      return ReturnCode.SKIP;
059    }
060    return ReturnCode.INCLUDE;
061  }
062
063  public static Filter createFilterFromArguments(ArrayList<byte[]> filterArguments) {
064    ArrayList<?> arguments = CompareFilter.extractArguments(filterArguments);
065    CompareOperator compareOp = (CompareOperator) arguments.get(0);
066    ByteArrayComparable comparator = (ByteArrayComparable) arguments.get(1);
067    return new QualifierFilter(compareOp, comparator);
068  }
069
070  /** Returns The filter serialized using pb */
071  @Override
072  public byte[] toByteArray() {
073    FilterProtos.QualifierFilter.Builder builder = FilterProtos.QualifierFilter.newBuilder();
074    builder.setCompareFilter(super.convert());
075    return builder.build().toByteArray();
076  }
077
078  /**
079   * Parse a serialized representation of {@link QualifierFilter}
080   * @param pbBytes A pb serialized {@link QualifierFilter} instance
081   * @return An instance of {@link QualifierFilter} made from <code>bytes</code>
082   * @throws DeserializationException if an error occurred
083   * @see #toByteArray
084   */
085  public static QualifierFilter parseFrom(final byte[] pbBytes) throws DeserializationException {
086    FilterProtos.QualifierFilter proto;
087    try {
088      proto = FilterProtos.QualifierFilter.parseFrom(pbBytes);
089    } catch (InvalidProtocolBufferException e) {
090      throw new DeserializationException(e);
091    }
092    final CompareOperator valueCompareOp =
093      CompareOperator.valueOf(proto.getCompareFilter().getCompareOp().name());
094    ByteArrayComparable valueComparator = null;
095    try {
096      if (proto.getCompareFilter().hasComparator()) {
097        valueComparator = ProtobufUtil.toComparator(proto.getCompareFilter().getComparator());
098      }
099    } catch (IOException ioe) {
100      throw new DeserializationException(ioe);
101    }
102    return new QualifierFilter(valueCompareOp, valueComparator);
103  }
104
105  /**
106   * Returns true if and only if the fields of the filter that are serialized are equal to the
107   * corresponding fields in other. Used for testing.
108   */
109  @Override
110  boolean areSerializedFieldsEqual(Filter o) {
111    if (o == this) {
112      return true;
113    }
114    if (!(o instanceof QualifierFilter)) {
115      return false;
116    }
117    return super.areSerializedFieldsEqual(o);
118  }
119
120  @Override
121  public boolean equals(Object obj) {
122    return obj instanceof Filter && areSerializedFieldsEqual((Filter) obj);
123  }
124
125  @Override
126  public int hashCode() {
127    return super.hashCode();
128  }
129}