/*
*
* 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.DeserializationException;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.protobuf.generated.FilterProtos;
import org.apache.hadoop.hbase.util.Bytes;
import java.util.ArrayList;
import com.google.common.base.Preconditions;
import com.google.protobuf.ByteString;
import com.google.protobuf.InvalidProtocolBufferException;
/**
* Pass results that have same row prefix.
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public class PrefixFilter extends FilterBase {
protected byte [] prefix = null;
protected boolean passedPrefix = false;
public PrefixFilter(final byte [] prefix) {
this.prefix = prefix;
}
public byte[] getPrefix() {
return prefix;
}
public boolean filterRowKey(byte[] buffer, int offset, int length) {
if (buffer == null || this.prefix == null)
return true;
if (length < prefix.length)
return true;
// if they are equal, return false => pass row
// else return true, filter row
// if we are passed the prefix, set flag
int cmp = Bytes.compareTo(buffer, offset, this.prefix.length, this.prefix, 0,
this.prefix.length);
if(cmp > 0) {
passedPrefix = true;
}
return cmp != 0;
}
public boolean filterAllRemaining() {
return passedPrefix;
}
public static Filter createFilterFromArguments(ArrayList<byte []> filterArguments) {
Preconditions.checkArgument(filterArguments.size() == 1,
"Expected 1 but got: %s", filterArguments.size());
byte [] prefix = ParseFilter.removeQuotesFromByteArray(filterArguments.get(0));
return new PrefixFilter(prefix);
}
/**
* @return The filter serialized using pb
*/
public byte [] toByteArray() {
FilterProtos.PrefixFilter.Builder builder =
FilterProtos.PrefixFilter.newBuilder();
if (this.prefix != null) builder.setPrefix(ByteString.copyFrom(this.prefix));
return builder.build().toByteArray();
}
/**
* @param pbBytes A pb serialized {@link PrefixFilter} instance
* @return An instance of {@link PrefixFilter} made from <code>bytes</code>
* @throws DeserializationException
* @see #toByteArray
*/
public static PrefixFilter parseFrom(final byte [] pbBytes)
throws DeserializationException {
FilterProtos.PrefixFilter proto;
try {
proto = FilterProtos.PrefixFilter.parseFrom(pbBytes);
} catch (InvalidProtocolBufferException e) {
throw new DeserializationException(e);
}
return new PrefixFilter(proto.hasPrefix()?proto.getPrefix().toByteArray():null);
}
/**
* @param other
* @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 PrefixFilter)) return false;
PrefixFilter other = (PrefixFilter)o;
return Bytes.equals(this.getPrefix(), other.getPrefix());
}
@Override
public String toString() {
return this.getClass().getSimpleName() + " " + Bytes.toStringBinary(this.prefix);
}
}