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/* * Copyright (c) 1997, 1999, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */   package javax.swing;   import java.io.*;import java.awt.Component;   /** * Monitors the progress of reading from some InputStream. This ProgressMonitor * is normally invoked in roughly this form: * <pre> * InputStream in = new BufferedInputStream( *                          new ProgressMonitorInputStream( *                                  parentComponent, *                                  "Reading " + fileName, *                                  new FileInputStream(fileName))); * </pre><p> * This creates a progress monitor to monitor the progress of reading * the input stream.  If it's taking a while, a ProgressDialog will * be popped up to inform the user.  If the user hits the Cancel button * an InterruptedIOException will be thrown on the next read. * All the right cleanup is done when the stream is closed. * * * <p> * * For further documentation and examples see * <a href="http://java.sun.com/docs/books/tutorial/uiswing/components/progress.html">How to Monitor Progress</a>, * a section in <em>The Java Tutorial.</em> * * @see ProgressMonitor * @see JOptionPane * @author James Gosling */public class ProgressMonitorInputStream extends FilterInputStream{    private ProgressMonitor monitor;    private int             nread = 0;    private int             size = 0;      /**     * Constructs an object to monitor the progress of an input stream.     *     * @param message Descriptive text to be placed in the dialog box     *                if one is popped up.     * @param parentComponent The component triggering the operation     *                        being monitored.     * @param in The input stream to be monitored.     */    public ProgressMonitorInputStream(Component parentComponent,                                      Object message,                                      InputStream in) {        super(in);        try {            size = in.available();        }        catch(IOException ioe) {            size = 0;        }        monitor = new ProgressMonitor(parentComponent, message, null, 0, size);    }      /**     * Get the ProgressMonitor object being used by this stream. Normally     * this isn't needed unless you want to do something like change the     * descriptive text partway through reading the file.     * @return the ProgressMonitor object used by this object     */    public ProgressMonitor getProgressMonitor() {        return monitor;    }      /**     * Overrides <code>FilterInputStream.read</code>     * to update the progress monitor after the read.     */    public int read() throws IOException {        int c = in.read();        if (c >= 0) monitor.setProgress(++nread);        if (monitor.isCanceled()) {            InterruptedIOException exc =                                    new InterruptedIOException("progress");            exc.bytesTransferred = nread;            throw exc;        }        return c;    }      /**     * Overrides <code>FilterInputStream.read</code>     * to update the progress monitor after the read.     */    public int read(byte b[]) throws IOException {        int nr = in.read(b);        if (nr > 0) monitor.setProgress(nread += nr);        if (monitor.isCanceled()) {            InterruptedIOException exc =                                    new InterruptedIOException("progress");            exc.bytesTransferred = nread;            throw exc;        }        return nr;    }      /**     * Overrides <code>FilterInputStream.read</code>     * to update the progress monitor after the read.     */    public int read(byte b[],                    int off,                    int len) throws IOException {        int nr = in.read(b, off, len);        if (nr > 0) monitor.setProgress(nread += nr);        if (monitor.isCanceled()) {            InterruptedIOException exc =                                    new InterruptedIOException("progress");            exc.bytesTransferred = nread;            throw exc;        }        return nr;    }      /**     * Overrides <code>FilterInputStream.skip</code>     * to update the progress monitor after the skip.     */    public long skip(long n) throws IOException {        long nr = in.skip(n);        if (nr > 0) monitor.setProgress(nread += nr);        return nr;    }      /**     * Overrides <code>FilterInputStream.close</code>     * to close the progress monitor as well as the stream.     */    public void close() throws IOException {        in.close();        monitor.close();    }      /**     * Overrides <code>FilterInputStream.reset</code>     * to reset the progress monitor as well as the stream.     */    public synchronized void reset() throws IOException {        in.reset();        nread = size - in.available();        monitor.setProgress(nread);    }}