JdkZlibEncoder.java — netty Source File

Source Code

/*
 * Copyright 2012 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:
 *
 *   https://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.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.util.concurrent.EventExecutor;
import io.netty.util.concurrent.PromiseNotifier;
import io.netty.util.internal.EmptyArrays;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.SystemPropertyUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;

import java.util.zip.CRC32;
import java.util.zip.Deflater;

/**
 * Compresses a {@link ByteBuf} using the deflate algorithm.
 */
public class JdkZlibEncoder extends ZlibEncoder {

    private static final InternalLogger logger = InternalLoggerFactory.getInstance(JdkZlibEncoder.class);

    /**
     * Maximum initial size for temporary heap buffers used for the compressed output. Buffer may still grow beyond
     * this if necessary.
     */
    private static final int MAX_INITIAL_OUTPUT_BUFFER_SIZE;
    /**
     * Max size for temporary heap buffers used to copy input data to heap.
     */
    private static final int MAX_INPUT_BUFFER_SIZE;

    private final ZlibWrapper wrapper;
    private final Deflater deflater;
    private volatile boolean finished;
    private volatile ChannelHandlerContext ctx;

    /*
     * GZIP support
     */
    private final CRC32 crc;
    private static final byte[] gzipHeader = {0x1f, (byte) 0x8b, Deflater.DEFLATED, 0, 0, 0, 0, 0, 0, 0};
    private boolean writeHeader = true;
// ... (297 more lines)