/**
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase.filter;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
import org.apache.hadoop.hbase.protobuf.generated.FilterProtos;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.CompareType;
import org.apache.hadoop.hbase.util.Bytes;
import java.util.ArrayList;
import com.google.common.base.Preconditions;
/**
* This is a generic filter to be used to filter by comparison. It takes an
* operator (equal, greater, not equal, etc) and a byte [] comparator.
* <p>
* To filter by row key, use {@link RowFilter}.
* <p>
* To filter by column qualifier, use {@link QualifierFilter}.
* <p>
* To filter by value, use {@link SingleColumnValueFilter}.
* <p>
* These filters can be wrapped with {@link SkipFilter} and {@link WhileMatchFilter}
* to add more control.
* <p>
* Multiple filters can be combined using {@link FilterList}.
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public abstract class CompareFilter extends FilterBase {
/** Comparison operators. */
public enum CompareOp {
/** less than */
LESS,
/** less than or equal to */
LESS_OR_EQUAL,
/** equals */
EQUAL,
/** not equal */
NOT_EQUAL,
/** greater than or equal to */
GREATER_OR_EQUAL,
/** greater than */
GREATER,
/** no operation */
NO_OP,
}
protected CompareOp compareOp;
protected ByteArrayComparable comparator;
/**
* Constructor.
* @param compareOp the compare op for row matching
* @param comparator the comparator for row matching
*/
public CompareFilter(final CompareOp compareOp,
final ByteArrayComparable comparator) {
this.compareOp = compareOp;
this.comparator = comparator;
}
/**
* @return operator
*/
public CompareOp getOperator() {
return compareOp;
}
/**
* @return the comparator
*/
public ByteArrayComparable getComparator() {
return comparator;
}
protected boolean doCompare(final CompareOp compareOp,
final ByteArrayComparable comparator, final byte [] data,
final int offset, final int length) {
if (compareOp == CompareOp.NO_OP) {
return true;
}
int compareResult = comparator.compareTo(data, offset, length);
switch (compareOp) {
case LESS:
return compareResult <= 0;
case LESS_OR_EQUAL:
return compareResult < 0;
case EQUAL:
return compareResult != 0;
case NOT_EQUAL:
return compareResult == 0;
case GREATER_OR_EQUAL:
return compareResult > 0;
case GREATER:
return compareResult >= 0;
default:
throw new RuntimeException("Unknown Compare op " +
compareOp.name());
}
}
public static ArrayList extractArguments(ArrayList<byte []> filterArguments) {
Preconditions.checkArgument(filterArguments.size() == 2,
"Expected 2 but got: %s", filterArguments.size());
CompareOp compareOp = ParseFilter.createCompareOp(filterArguments.get(0));
ByteArrayComparable comparator = ParseFilter.createComparator(
ParseFilter.removeQuotesFromByteArray(filterArguments.get(1)));
if (comparator instanceof RegexStringComparator ||
comparator instanceof SubstringComparator) {
if (compareOp != CompareOp.EQUAL &&
compareOp != CompareOp.NOT_EQUAL) {
throw new IllegalArgumentException ("A regexstring comparator and substring comparator" +
" can only be used with EQUAL and NOT_EQUAL");
}
}
ArrayList arguments = new ArrayList();
arguments.add(compareOp);
arguments.add(comparator);
return arguments;
}
/**
* @return A pb instance to represent this instance.
*/
FilterProtos.CompareFilter convert() {
FilterProtos.CompareFilter.Builder builder =
FilterProtos.CompareFilter.newBuilder();
HBaseProtos.CompareType compareOp = CompareType.valueOf(this.compareOp.name());
builder.setCompareOp(compareOp);
if (this.comparator != null) builder.setComparator(ProtobufUtil.toComparator(this.comparator));
return builder.build();
}
/**
*
* @param o
* @return true if and only if the fields of the filter that are serialized
* are equal to the corresponding fields in other. Used for testing.
*/
boolean areSerializedFieldsEqual(Filter o) {
if (o == this) return true;
if (!(o instanceof CompareFilter)) return false;
CompareFilter other = (CompareFilter)o;
return this.getOperator().equals(other.getOperator()) &&
(this.getComparator() == other.getComparator()
|| this.getComparator().areSerializedFieldsEqual(other.getComparator()));
}
@Override
public String toString() {
return String.format("%s (%s, %s)",
this.getClass().getSimpleName(),
this.compareOp.name(),
Bytes.toStringBinary(this.comparator.getValue()));
}
}