javax.swing

Class ProgressMonitorInputStream

  • All Implemented Interfaces:
    Closeable, AutoCloseable 

    public class ProgressMonitorInputStream
extends FilterInputStream
    Monitors the progress of reading from some InputStream. This ProgressMonitor is normally invoked in roughly this form: 
     InputStream in = new BufferedInputStream(
                          new ProgressMonitorInputStream(
                                  parentComponent,
                                  "Reading " + fileName,
                                  new FileInputStream(fileName)));

    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.

    For further documentation and examples see How to Monitor Progress, a section in The Java Tutorial.

    See Also:
    ProgressMonitor, JOptionPane

    • Method Summary

      Modifier and Type Method and Description
      void close()
      Overrides FilterInputStream.close to close the progress monitor as well as the stream.
      ProgressMonitor getProgressMonitor()
      Get the ProgressMonitor object being used by this stream.
      int read()
      Overrides FilterInputStream.read to update the progress monitor after the read.
      int read(byte[] b)
      Overrides FilterInputStream.read to update the progress monitor after the read.
      int read(byte[] b, int off, int len)
      Overrides FilterInputStream.read to update the progress monitor after the read.
      void reset()
      Overrides FilterInputStream.reset to reset the progress monitor as well as the stream.
      long skip(long n)
      Overrides FilterInputStream.skip to update the progress monitor after the skip.

    • Constructor Detail

      • ProgressMonitorInputStream

        public ProgressMonitorInputStream(Component parentComponent,
                                  Object message,
                                  InputStream in)
        Constructs an object to monitor the progress of an input stream.
        Parameters:
        message - Descriptive text to be placed in the dialog box if one is popped up.
        parentComponent - The component triggering the operation being monitored.
        in - The input stream to be monitored.

    • Method Detail

      • getProgressMonitor

        public ProgressMonitor getProgressMonitor()
        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.
        Returns:
        the ProgressMonitor object used by this object

      • read

        public int read()
         throws IOException
        Overrides FilterInputStream.read to update the progress monitor after the read.
        Overrides:
        read in class  FilterInputStream
        Returns:
        the next byte of data, or -1 if the end of the stream is reached.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterInputStream.in

      • read

        public int read(byte[] b)
         throws IOException
        Overrides FilterInputStream.read to update the progress monitor after the read.
        Overrides:
        read in class  FilterInputStream
        Parameters:
        b - the buffer into which the data is read.
        Returns:
        the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterInputStream.read(byte[], int, int)

      • read

        public int read(byte[] b,
                int off,
                int len)
         throws IOException
        Overrides FilterInputStream.read to update the progress monitor after the read.
        Overrides:
        read in class  FilterInputStream
        Parameters:
        b - the buffer into which the data is read.
        off - the start offset in the destination array b
        len - the maximum number of bytes read.
        Returns:
        the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterInputStream.in

      • skip

        public long skip(long n)
          throws IOException
        Overrides FilterInputStream.skip to update the progress monitor after the skip.
        Overrides:
        skip in class  FilterInputStream
        Parameters:
        n - the number of bytes to be skipped.
        Returns:
        the actual number of bytes skipped.
        Throws:
        IOException - if the stream does not support seek, or if some other I/O error occurs.