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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * 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 com.jcraft.jzlib.Inflater;
import com.jcraft.jzlib.JZlib;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.channel.ChannelHandlerContext;
import io.netty.util.internal.ObjectUtil;

import java.util.List;

public class JZlibDecoder extends ZlibDecoder {

    private final Inflater z = new Inflater();
    private byte[] dictionary;
    private volatile boolean finished;

    /**
     * Creates a new instance with the default wrapper ({@link ZlibWrapper#ZLIB}).
     *
     * @throws DecompressionException if failed to initialize zlib
     */
    public JZlibDecoder() {
        this(ZlibWrapper.ZLIB, 0);
    }

    /**
     * Creates a new instance with the default wrapper ({@link ZlibWrapper#ZLIB})
     * and specified maximum buffer allocation.
     *
     * @param maxAllocation
     *          Maximum size of the decompression buffer. Must be >= 0.
     *          If zero, maximum size is decided by the {@link ByteBufAllocator}.
     *
     * @throws DecompressionException if failed to initialize zlib
     */
    public JZlibDecoder(int maxAllocation) {
        this(ZlibWrapper.ZLIB, maxAllocation);
    }

    /**
     * Creates a new instance with the specified wrapper.
     *
     * @throws DecompressionException if failed to initialize zlib
     */
    public JZlibDecoder(ZlibWrapper wrapper) {
        this(wrapper, 0);
    }

    /**
     * Creates a new instance with the specified wrapper and maximum buffer allocation.
     *
     * @param maxAllocation
     *          Maximum size of the decompression buffer. Must be >= 0.
     *          If zero, maximum size is decided by the {@link ByteBufAllocator}.
     *
     * @throws DecompressionException if failed to initialize zlib
     */
    public JZlibDecoder(ZlibWrapper wrapper, int maxAllocation) {
        super(maxAllocation);

        ObjectUtil.checkNotNull(wrapper, "wrapper");

        int resultCode = z.init(ZlibUtil.convertWrapperType(wrapper));
        if (resultCode != JZlib.Z_OK) {
            ZlibUtil.fail(z, "initialization failure", resultCode);
        }
    }

    /**
     * Creates a new instance with the specified preset dictionary. The wrapper
     * is always {@link ZlibWrapper#ZLIB} because it is the only format that
     * supports the preset dictionary.
     *
     * @throws DecompressionException if failed to initialize zlib
     */
    public JZlibDecoder(byte[] dictionary) {
        this(dictionary, 0);
    }

    /**
     * Creates a new instance with the specified preset dictionary and maximum buffer allocation.
     * The wrapper is always {@link ZlibWrapper#ZLIB} because it is the only format that
     * supports the preset dictionary.
     *
     * @param maxAllocation
     *          Maximum size of the decompression buffer. Must be >= 0.
     *          If zero, maximum size is decided by the {@link ByteBufAllocator}.
     *
     * @throws DecompressionException if failed to initialize zlib
     */
    public JZlibDecoder(byte[] dictionary, int maxAllocation) {
        super(maxAllocation);
        this.dictionary = ObjectUtil.checkNotNull(dictionary, "dictionary");
        int resultCode;
        resultCode = z.inflateInit(JZlib.W_ZLIB);
        if (resultCode != JZlib.Z_OK) {
            ZlibUtil.fail(z, "initialization failure", resultCode);
        }
    }

    /**
     * Returns {@code true} if and only if the end of the compressed stream
     * has been reached.
     */
    @Override
    public boolean isClosed() {
        return finished;
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List out) throws Exception {
        if (finished) {
            // Skip data received after finished.
            in.skipBytes(in.readableBytes());
            return;
        }

        final int inputLength = in.readableBytes();
        if (inputLength == 0) {
            return;
        }

        try {
            // Configure input.
            z.avail_in = inputLength;
            if (in.hasArray()) {
                z.next_in = in.array();
                z.next_in_index = in.arrayOffset() + in.readerIndex();
            } else {
                byte[] array = new byte[inputLength];
                in.getBytes(in.readerIndex(), array);
                z.next_in = array;
                z.next_in_index = 0;
            }
            final int oldNextInIndex = z.next_in_index;

            // Configure output.
            ByteBuf decompressed = prepareDecompressBuffer(ctx, null, inputLength << 1);

            try {
                loop: for (;;) {
                    decompressed = prepareDecompressBuffer(ctx, decompressed, z.avail_in << 1);
                    z.avail_out = decompressed.writableBytes();
                    z.next_out = decompressed.array();
                    z.next_out_index = decompressed.arrayOffset() + decompressed.writerIndex();
                    int oldNextOutIndex = z.next_out_index;

                    // Decompress 'in' into 'out'
                    int resultCode = z.inflate(JZlib.Z_SYNC_FLUSH);
                    int outputLength = z.next_out_index - oldNextOutIndex;
                    if (outputLength > 0) {
                        decompressed.writerIndex(decompressed.writerIndex() + outputLength);
                    }

                    switch (resultCode) {
                    case JZlib.Z_NEED_DICT:
                        if (dictionary == null) {
                            ZlibUtil.fail(z, "decompression failure", resultCode);
                        } else {
                            resultCode = z.inflateSetDictionary(dictionary, dictionary.length);
                            if (resultCode != JZlib.Z_OK) {
                                ZlibUtil.fail(z, "failed to set the dictionary", resultCode);
                            }
                        }
                        break;
                    case JZlib.Z_STREAM_END:
                        finished = true; // Do not decode anymore.
                        z.inflateEnd();
                        break loop;
                    case JZlib.Z_OK:
                        break;
                    case JZlib.Z_BUF_ERROR:
                        if (z.avail_in <= 0) {
                            break loop;
                        }
                        break;
                    default:
                        ZlibUtil.fail(z, "decompression failure", resultCode);
                    }
                }
            } finally {
                in.skipBytes(z.next_in_index - oldNextInIndex);
                if (decompressed.isReadable()) {
                    out.add(decompressed);
                } else {
                    decompressed.release();
                }
            }
        } finally {
            // Deference the external references explicitly to tell the VM that
            // the allocated byte arrays are temporary so that the call stack
            // can be utilized.
            // I'm not sure if the modern VMs do this optimization though.
            z.next_in = null;
            z.next_out = null;
        }
    }

    @Override
    protected void decompressionBufferExhausted(ByteBuf buffer) {
        finished = true;
    }
}
    

    

    

            

    

            



    
    






    
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