net.jpountz.xxhash.XXHash64 Maven / Gradle / Ivy
package net.jpountz.xxhash;
import java.nio.ByteBuffer;
/*
* Licensed 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.
*/
/**
* A 64-bits hash.
*
* Instances of this class are thread-safe.
*/
public abstract class XXHash64 {
/**
* Computes the 64-bits hash of buf[off:off+len]
using seed
* seed
.
*
* @param buf the input data
* @param off the start offset in buf
* @param len the number of bytes to hash
* @param seed the seed to use
* @return the hash value
*/
public abstract long hash(byte[] buf, int off, int len, long seed);
/**
* Computes the hash of the given slice of the {@link ByteBuffer}.
* {@link ByteBuffer#position() position} and {@link ByteBuffer#limit() limit}
* are not modified.
*
* @param buf the input data
* @param off the start offset in buf
* @param len the number of bytes to hash
* @param seed the seed to use
* @return the hash value
*/
public abstract long hash(ByteBuffer buf, int off, int len, long seed);
/**
* Computes the hash of the given {@link ByteBuffer}. The
* {@link ByteBuffer#position() position} is moved in order to reflect bytes
* which have been read.
*
* @param buf the input data
* @param seed the seed to use
* @return the hash value
*/
public final long hash(ByteBuffer buf, long seed) {
final long hash = hash(buf, buf.position(), buf.remaining(), seed);
buf.position(buf.limit());
return hash;
}
@Override
public String toString() {
return getClass().getSimpleName();
}
}