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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 2014 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.spdy;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;

import java.util.zip.DataFormatException;
import java.util.zip.Inflater;

import static io.netty.handler.codec.spdy.SpdyCodecUtil.*;

final class SpdyHeaderBlockZlibDecoder extends SpdyHeaderBlockRawDecoder {

    private static final int DEFAULT_BUFFER_CAPACITY = 4096;
    private static final SpdyProtocolException INVALID_HEADER_BLOCK =
            new SpdyProtocolException("Invalid Header Block");

    private final Inflater decompressor = new Inflater();

    private ByteBuf decompressed;

    SpdyHeaderBlockZlibDecoder(SpdyVersion spdyVersion, int maxHeaderSize) {
        super(spdyVersion, maxHeaderSize);
    }

    @Override
    void decode(ByteBufAllocator alloc, ByteBuf headerBlock, SpdyHeadersFrame frame) throws Exception {
        int len = setInput(headerBlock);

        int numBytes;
        do {
            numBytes = decompress(alloc, frame);
        } while (numBytes > 0);

        // z_stream has an internal 64-bit hold buffer
        // it is always capable of consuming the entire input
        if (decompressor.getRemaining() != 0) {
            // we reached the end of the deflate stream
            throw INVALID_HEADER_BLOCK;
        }

        headerBlock.skipBytes(len);
    }

    private int setInput(ByteBuf compressed) {
        int len = compressed.readableBytes();

        if (compressed.hasArray()) {
            decompressor.setInput(compressed.array(), compressed.arrayOffset() + compressed.readerIndex(), len);
        } else {
            byte[] in = new byte[len];
            compressed.getBytes(compressed.readerIndex(), in);
            decompressor.setInput(in, 0, in.length);
        }

        return len;
    }

    private int decompress(ByteBufAllocator alloc, SpdyHeadersFrame frame) throws Exception {
        ensureBuffer(alloc);
        byte[] out = decompressed.array();
        int off = decompressed.arrayOffset() + decompressed.writerIndex();
        try {
            int numBytes = decompressor.inflate(out, off, decompressed.writableBytes());
            if (numBytes == 0 && decompressor.needsDictionary()) {
                try {
                    decompressor.setDictionary(SPDY_DICT);
                } catch (IllegalArgumentException ignored) {
                    throw INVALID_HEADER_BLOCK;
                }
                numBytes = decompressor.inflate(out, off, decompressed.writableBytes());
            }
            if (frame != null) {
                decompressed.writerIndex(decompressed.writerIndex() + numBytes);
                decodeHeaderBlock(decompressed, frame);
                decompressed.discardReadBytes();
            }

            return numBytes;
        } catch (DataFormatException e) {
            throw new SpdyProtocolException("Received invalid header block", e);
        }
    }

    private void ensureBuffer(ByteBufAllocator alloc) {
        if (decompressed == null) {
            decompressed = alloc.heapBuffer(DEFAULT_BUFFER_CAPACITY);
        }
        decompressed.ensureWritable(1);
    }

    @Override
    void endHeaderBlock(SpdyHeadersFrame frame) throws Exception {
        super.endHeaderBlock(frame);
        releaseBuffer();
    }

    @Override
    public void end() {
        super.end();
        releaseBuffer();
        decompressor.end();
    }

    private void releaseBuffer() {
        if (decompressed != null) {
            decompressed.release();
            decompressed = null;
        }
    }
}