bodyoutputstream.java

OSGI这是一个中间件,与UPNP齐名,是用于移植到嵌入式平台之上

/*
 * Copyright (c) 2003, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - 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.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS 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 THE
 * COPYRIGHT OWNER OR 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.
 */

package org.knopflerfish.bundle.http;

import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.OutputStream;

public class BodyOutputStream extends BufferedOutputStream {

    // private fields

    private int totalCount = 0;

    private int maxCount = Integer.MAX_VALUE;

    private boolean committed = false;

    private ResponseImpl response = null;

    // constructors

    BodyOutputStream(OutputStream out, ResponseImpl response, int size) {

        super(out);

        this.response = response;

        setBufferSize(size);
    }

    // package methods

    void setContentLength(int contentLength) {

        if (!committed)
            maxCount = contentLength;
    }

    int getBufferByteCount() {
        return count;
    }

    public synchronized void setBufferSize(int size) {

        if (totalCount != 0)
            throw new IllegalStateException(
                    "Buffer size cannot be changed when data has been written");

        if (size < 0)
            throw new IllegalArgumentException(
                    "Buffer size must not be negative: " + size);

        if (size > buf.length)
            buf = new byte[size];
    }

    public int getBufferSize() {
        return buf.length;
    }

    public synchronized void reset() {

        totalCount = 0;
        count = 0;
    }

    public synchronized boolean isCommitted() {
        return committed;
    }

    synchronized void flush(boolean commit) throws IOException {

        if (commit)
            flushBuffer();

        out.flush();
    }

    // protected methods

    protected void flushBuffer() throws IOException {

        if (!committed && response != null) {
            out.write(response.getHeaders());
            committed = true;
        }

        out.write(buf, 0, count);
        count = 0;
    }

    // extends BufferedOutputStream

    public synchronized void write(int b) throws IOException {

        if (count >= buf.length)
            flushBuffer();

        if (totalCount++ < maxCount)
            buf[count++] = (byte) b;
        else
            flushBuffer();
    }

    public synchronized void write(byte b[], int off, int len)
            throws IOException {

        if (len >= buf.length) {
            flushBuffer();
            out.write(b, off, len);
        } else {
            if (len > buf.length - count)
                flushBuffer();
            System.arraycopy(b, off, buf, count, len);
            totalCount += len;
            count += len;
        }
    }

    public void flush() {
    }

    public void close() {
    }

} // BodyOutputStream