159 lines
4.8 KiB
Java
159 lines
4.8 KiB
Java
|
/*
|
||
|
* Copyright 2016 The Netty Project
|
||
|
*
|
||
|
* The Netty Project 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 io.netty.handler.codec.compression;
|
||
|
|
||
|
import io.netty.buffer.ByteBuf;
|
||
|
import io.netty.util.internal.ObjectUtil;
|
||
|
import io.netty.util.internal.PlatformDependent;
|
||
|
|
||
|
import java.lang.reflect.Method;
|
||
|
import java.nio.ByteBuffer;
|
||
|
import java.util.zip.Adler32;
|
||
|
import java.util.zip.CRC32;
|
||
|
import java.util.zip.Checksum;
|
||
|
|
||
|
/**
|
||
|
* {@link Checksum} implementation which can directly act on a {@link ByteBuf}.
|
||
|
*
|
||
|
* Implementations may optimize access patterns depending on if the {@link ByteBuf} is backed by a
|
||
|
* byte array ({@link ByteBuf#hasArray()} is {@code true}) or not.
|
||
|
*/
|
||
|
abstract class ByteBufChecksum implements Checksum {
|
||
|
private static final Method ADLER32_UPDATE_METHOD;
|
||
|
private static final Method CRC32_UPDATE_METHOD;
|
||
|
|
||
|
static {
|
||
|
// See if we can use fast-path when using ByteBuf that is not heap based as Adler32 and CRC32 added support
|
||
|
// for update(ByteBuffer) in JDK8.
|
||
|
ADLER32_UPDATE_METHOD = updateByteBuffer(new Adler32());
|
||
|
CRC32_UPDATE_METHOD = updateByteBuffer(new CRC32());
|
||
|
}
|
||
|
|
||
|
private static Method updateByteBuffer(Checksum checksum) {
|
||
|
if (PlatformDependent.javaVersion() >= 8) {
|
||
|
try {
|
||
|
Method method = checksum.getClass().getDeclaredMethod("update", ByteBuffer.class);
|
||
|
method.invoke(method, ByteBuffer.allocate(1));
|
||
|
return method;
|
||
|
} catch (Throwable ignore) {
|
||
|
return null;
|
||
|
}
|
||
|
}
|
||
|
return null;
|
||
|
}
|
||
|
|
||
|
protected Checksum checksum;
|
||
|
|
||
|
private ByteBufChecksum(Checksum checksum) {
|
||
|
this.checksum = checksum;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public void update(int b) {
|
||
|
checksum.update(b);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* @see {@link #update(byte[], int, int)}.
|
||
|
*/
|
||
|
abstract void update(ByteBuf b, int off, int len);
|
||
|
|
||
|
/**
|
||
|
* Returns {@code true} if {@link ByteBuffer} is supported without memory copy.
|
||
|
*/
|
||
|
abstract boolean isSupportingByteBuffer();
|
||
|
|
||
|
@Override
|
||
|
public void update(byte[] b, int off, int len) {
|
||
|
checksum.update(b, off, len);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public long getValue() {
|
||
|
return checksum.getValue();
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public void reset() {
|
||
|
checksum.reset();
|
||
|
}
|
||
|
|
||
|
static ByteBufChecksum wrapChecksum(Checksum checksum) {
|
||
|
ObjectUtil.checkNotNull(checksum, "checksum");
|
||
|
if (checksum instanceof Adler32 && ADLER32_UPDATE_METHOD != null) {
|
||
|
return new ReflectiveByteBufChecksum(checksum, ADLER32_UPDATE_METHOD);
|
||
|
}
|
||
|
if (checksum instanceof CRC32 && CRC32_UPDATE_METHOD != null) {
|
||
|
return new ReflectiveByteBufChecksum(checksum, CRC32_UPDATE_METHOD);
|
||
|
}
|
||
|
return new SlowByteBufChecksum(checksum);
|
||
|
}
|
||
|
|
||
|
private static final class ReflectiveByteBufChecksum extends ByteBufChecksum {
|
||
|
private final Method method;
|
||
|
|
||
|
ReflectiveByteBufChecksum(Checksum checksum, Method method) {
|
||
|
super(checksum);
|
||
|
this.method = method;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
void update(ByteBuf b, int off, int len) {
|
||
|
if (b.hasArray()) {
|
||
|
update(b.array(), b.arrayOffset() + off, len);
|
||
|
} else {
|
||
|
try {
|
||
|
method.invoke(checksum, CompressionUtil.safeNioBuffer(b));
|
||
|
} catch (Throwable cause) {
|
||
|
throw new Error();
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
boolean isSupportingByteBuffer() {
|
||
|
return true;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
private static final class SlowByteBufChecksum extends ByteBufChecksum {
|
||
|
|
||
|
SlowByteBufChecksum(Checksum checksum) {
|
||
|
super(checksum);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
void update(ByteBuf b, int off, int len) {
|
||
|
if (b.hasArray()) {
|
||
|
update(b.array(), b.arrayOffset() + off, len);
|
||
|
} else {
|
||
|
ByteBuf heapBuffer = b.alloc().heapBuffer(len);
|
||
|
try {
|
||
|
heapBuffer.writeBytes(b, off, len);
|
||
|
update(heapBuffer.array(), heapBuffer.arrayOffset(), len);
|
||
|
} finally {
|
||
|
heapBuffer.release();
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
boolean isSupportingByteBuffer() {
|
||
|
return false;
|
||
|
}
|
||
|
}
|
||
|
}
|