src/main/java/com/alibaba/com/caucho/hessian/io/Hessian2StreamingInput.java

/*
 * Copyright (c) 2001-2008 Caucho Technology, Inc.  All rights reserved.
 *
 * The Apache Software License, Version 1.1
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Caucho Technology (http://www.caucho.com/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Burlap", "Resin", and "Caucho" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    info@caucho.com.
 *
 * 5. Products derived from this software may not be called "Resin"
 *    nor may "Resin" appear in their names without prior written
 *    permission of Caucho Technology.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Scott Ferguson
 */

package com.alibaba.com.caucho.hessian.io;

import java.io.IOException;
import java.io.InputStream;

/**
 * Output stream for Hessian 2 streaming requests.
 */
public class Hessian2StreamingInput {
    private Hessian2Input _in;

    /**
     * Creates a new Hessian input stream, initialized with an
     * underlying input stream.
     *
     * @param is the underlying output stream.
     */
    public Hessian2StreamingInput(InputStream is) {
        _in = new Hessian2Input(new StreamingInputStream(is));
    }

    /**
     * Read the next object
     */
    public Object readObject()
            throws IOException {
        return _in.readStreamingObject();
    }

    /**
     * Close the output.
     */
    public void close()
            throws IOException {
        _in.close();
    }

    static class StreamingInputStream extends InputStream {
        private InputStream _is;
        private int _length;

        StreamingInputStream(InputStream is) {
            _is = is;
        }

        @Override
        public int read()
                throws IOException {
            InputStream is = _is;

            while (_length == 0) {
                int code = is.read();

                if (code < 0)
                    return -1;
                else if (code != 'p' && code != 'P')
                    throw new HessianProtocolException("expected streaming packet at 0x"
                            + Integer.toHexString(code & 0xff));

                int d1 = is.read();
                int d2 = is.read();

                if (d2 < 0)
                    return -1;

                _length = (d1 << 8) + d2;
            }

            _length--;
            return is.read();
        }

        @Override
        public int read(byte[] buffer, int offset, int length)
                throws IOException {
            InputStream is = _is;

            while (_length == 0) {
                int code = is.read();

                if (code < 0)
                    return -1;
                else if (code != 'p' && code != 'P') {
                    throw new HessianProtocolException("expected streaming packet at 0x"
                            + Integer.toHexString(code & 0xff)
                            + " (" + (char) code + ")");
                }

                int d1 = is.read();
                int d2 = is.read();

                if (d2 < 0)
                    return -1;

                _length = (d1 << 8) + d2;
            }

            int sublen = _length;
            if (length < sublen)
                sublen = length;

            sublen = is.read(buffer, offset, sublen);

            if (sublen < 0)
                return -1;

            _length -= sublen;

            return sublen;
        }
    }
}