| /** |
| * 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.io; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| /** |
| * Interface supported by {@link org.apache.hadoop.io.WritableComparable} |
| * types supporting ordering/permutation by a representative set of bytes. |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Stable |
| public abstract class BinaryComparable implements Comparable<BinaryComparable> { |
| |
| /** |
| * Return n st bytes 0..n-1 from {#getBytes()} are valid. |
| */ |
| public abstract int getLength(); |
| |
| /** |
| * Return representative byte array for this instance. |
| */ |
| public abstract byte[] getBytes(); |
| |
| /** |
| * Compare bytes from {#getBytes()}. |
| * @see org.apache.hadoop.io.WritableComparator#compareBytes(byte[],int,int,byte[],int,int) |
| */ |
| @Override |
| public int compareTo(BinaryComparable other) { |
| if (this == other) |
| return 0; |
| return WritableComparator.compareBytes(getBytes(), 0, getLength(), |
| other.getBytes(), 0, other.getLength()); |
| } |
| |
| /** |
| * Compare bytes from {#getBytes()} to those provided. |
| */ |
| public int compareTo(byte[] other, int off, int len) { |
| return WritableComparator.compareBytes(getBytes(), 0, getLength(), |
| other, off, len); |
| } |
| |
| /** |
| * Return true if bytes from {#getBytes()} match. |
| */ |
| @Override |
| public boolean equals(Object other) { |
| if (!(other instanceof BinaryComparable)) |
| return false; |
| BinaryComparable that = (BinaryComparable)other; |
| if (this.getLength() != that.getLength()) |
| return false; |
| return this.compareTo(that) == 0; |
| } |
| |
| /** |
| * Return a hash of the bytes returned from {#getBytes()}. |
| * @see org.apache.hadoop.io.WritableComparator#hashBytes(byte[],int) |
| */ |
| @Override |
| public int hashCode() { |
| return WritableComparator.hashBytes(getBytes(), getLength()); |
| } |
| |
| } |