BinaryComparable.java
上传用户:quxuerui
上传日期:2018-01-08
资源大小:41811k
文件大小:2k
- /**
- * 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;
- /**
- * Interface supported by {@link org.apache.hadoop.io.WritableComparable}
- * types supporting ordering/permutation by a representative set of bytes.
- */
- 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)
- */
- 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.
- */
- 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)
- */
- public int hashCode() {
- return WritableComparator.hashBytes(getBytes(), getLength());
- }
- }