org.apache.hadoop.hive.ql.io.HiveKey Maven / Gradle / Ivy
/*
* 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.hive.ql.io;
import org.apache.hadoop.io.BytesWritable;
import org.apache.hadoop.io.WritableComparator;
/**
* HiveKey is a simple wrapper on Text which allows us to set the hashCode
* easily. hashCode is used for hadoop partitioner.
*/
public class HiveKey extends BytesWritable {
private static final int LENGTH_BYTES = 4;
private int hashCode;
private boolean hashCodeValid;
private transient int distKeyLength;
public HiveKey() {
hashCodeValid = false;
}
public HiveKey(byte[] bytes, int hashcode) {
super(bytes);
hashCode = hashcode;
hashCodeValid = true;
}
public void setHashCode(int myHashCode) {
hashCodeValid = true;
hashCode = myHashCode;
}
@Override
public int hashCode() {
if (!hashCodeValid) {
throw new RuntimeException("Cannot get hashCode() from deserialized "
+ HiveKey.class);
}
return hashCode;
}
public void setDistKeyLength(int distKeyLength) {
this.distKeyLength = distKeyLength;
}
public int getDistKeyLength() {
return distKeyLength;
}
/** A Comparator optimized for HiveKey. */
public static class Comparator extends WritableComparator {
public Comparator() {
super(HiveKey.class);
}
/**
* Compare the buffers in serialized form.
*/
@Override
public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
return compareBytes(b1, s1 + LENGTH_BYTES, l1 - LENGTH_BYTES, b2, s2
+ LENGTH_BYTES, l2 - LENGTH_BYTES);
}
}
static {
WritableComparator.define(HiveKey.class, new Comparator());
}
}