echopoint.tucana.InputStreamDownloadProvider.java Source code

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Here is the source code for echopoint.tucana.InputStreamDownloadProvider.java

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/*
 * This file is part of the Echo Point Project.  This project is a
 * collection of Components that have extended the Echo Web Application
 * Framework Version 3.
 *
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 */

package echopoint.tucana;

import static java.util.UUID.randomUUID;

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

import org.apache.commons.io.IOUtils;

/**
 * A download provider implementation that streams the contents of the
 * specified input stream to the client request output stream on demand.
 *
 * @author Rakesh 2009-08-21
 * @version $Id$
 */
public class InputStreamDownloadProvider extends AbstractDownloadProvider {
    private static final long serialVersionUID = 1L;

    /**
     * The input stream to use as the data source to write to the client
     * output stream.
     */
    @SuppressWarnings({ "TransientFieldNotInitialized" })
    private final transient InputStream stream;

    /**
     * Create a new download provider instance for the specified input
     * stream.
     *
     * @param stream The input stream from which to stream the output.
     */
    public InputStreamDownloadProvider(final InputStream stream) {
        this.stream = stream;
    }

    public String getContentType() {
        return (contentType == null) ? "binary/octet-stream" : contentType;
    }

    public void writeFile(final OutputStream out) throws IOException {
        status = Status.inprogress;

        try {
            IOUtils.copy(stream, out);
            out.flush();
        } catch (IOException e) {
            status = Status.failed;
            throw e;
        }

        status = Status.completed;
    }

    @Override
    public String getFileName() {
        return (fileName == null) ? randomUUID().toString() : fileName;
    }
}