path: root/libjava/classpath/javax/sound/sampled/DataLine.java

/*
   Copyright (C) 2005-2007 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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any later version.

GNU Classpath is distributed in the hope that it will be useful, but
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General Public License for more details.

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02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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package javax.sound.sampled;

import gnu.java.lang.CPStringBuilder;

/**
 * The DataLine interface adds data-related functionality to the Line
 * interface.  For example, it adds methods to start and stop the data
 * on the line.
 * @since 1.3
 */
public interface DataLine extends Line
{
  /**
   * This class extends Line.Info with information specific to DataLine.
   * In particular it adds information about buffer sizes, and about supported
   * audio formats.
   * @since 1.3
   */
  class Info extends Line.Info
  {
    private int minBufferSize;
    private int maxBufferSize;
    private AudioFormat[] formats;

    /**
     * Create a new Info given the line's class and a supported
     * audio format.  The buffer sizes default to AudioSystem.NOT_SPECIFIED.
     * @param klass the class of the line
     * @param fmt the supported format
     */
    public Info(Class<?> klass, AudioFormat fmt)
    {
      super(klass);
      this.minBufferSize = AudioSystem.NOT_SPECIFIED;
      this.maxBufferSize = AudioSystem.NOT_SPECIFIED;
      this.formats = new AudioFormat[] { fmt };
    }

    /**
     * Create a new Info given the line's class, the supported audio formats,
     * the minimum buffer size, and the maximum buffer size.
     * @param klass the class of the linee
     * @param fmts the supported audio formats
     * @param minSize the minimum buffer size
     * @param maxSize the maximum buffer size
     */
    public Info(Class<?> klass, AudioFormat[] fmts, int minSize, int maxSize)
    {
      super(klass);
      this.minBufferSize = minSize;
      this.maxBufferSize = maxSize;
      this.formats = fmts;
    }

    /**
     * Create a new Info given the line's class, a supported
     * audio format, and a buffer size.  Both the minimum and maximum
     * sizes are set from this size.
     * @param klass the class of the line
     * @param fmt the supported format
     * @param size the buffer size
     */
    public Info(Class<?> klass, AudioFormat fmt, int size)
    {
      super(klass);
      this.minBufferSize = size;
      this.maxBufferSize = size;
      this.formats = new AudioFormat[] { fmt };
    }

    /**
     * Return the supported audio formats.
     */
    public AudioFormat[] getFormats()
    {
      // FIXME: clone?
      return formats;
    }

    /**
     * Return the maximum buffer size.
     */
    public int getMaxBufferSize()
    {
      return maxBufferSize;
    }

    /**
     * Return the minimum buffer size.
     */
    public int getMinBufferSize()
    {
      return minBufferSize;
    }

    /**
     * Return true if the indicated audio format is supported by this
     * Info, false otherwise.
     * @param fmt the audio format
     * @return true if the format is supported
     */
    public boolean isFormatSupported(AudioFormat fmt)
    {
      for (int i = 0; i < formats.length; ++i)
        {
          if (fmt.matches(formats[i]))
            return true;
        }
      return false;
    }

    /**
     * Return true if this Info matches another Info object.
     */
    public boolean matches(Line.Info o)
    {
      if (! super.matches(o) || ! (o instanceof Info))
        return false;

      Info other = (Info) o;
      if (minBufferSize < other.minBufferSize ||
          maxBufferSize > other.maxBufferSize)
        return false;

      for (int i = 0; i < formats.length; ++i)
        {
          boolean ok = false;
          for (int j = 0; j < other.formats.length; ++j)
            {
              if (formats[i].matches(other.formats[j]))
                {
                  ok = true;
                  break;
                }
            }
          if (! ok)
            return false;
        }

      return true;
    }

    /**
     * Return a description of this Info object.
     */
    public String toString()
    {
      CPStringBuilder result = new CPStringBuilder();
      result.append("formats: [");
      for (int i = 0; i < formats.length; ++i)
        {
          if (i > 0)
            result.append(", ");
          result.append(formats[i].toString());
        }

      result.append("]; minBufferSize: ");
      result.append(minBufferSize);
      result.append("; maxBufferSize: ");
      result.append(maxBufferSize);
      return result.toString();
    }

  } // end class: Info

  /**
   * Return the number of bytes currently available on this DataLine.
   */
  int available();

  /**
   * This method blocks until whatever data is buffered in the
   * DataLine's internal buffer has been drained.
   */
  void drain();

  /**
   * This flushes the DataLine by discarding any buffered data.
   */
  void flush();

  /**
   * Returns the size of the DataLine's internal buffer, in bytes.
   */
  int getBufferSize();

  /**
   * Return the current format of the data associated with this DataLine.
   */
  AudioFormat getFormat();

  /**
   * Return the current frame position.
   */
  int getFramePosition();

  /**
   * Return the volume level for this DataLine.
   */
  float getLevel();

  /**
   * Return the current frame position.
   * @since 1.5
   */
  long getLongFramePosition();

  /**
   * Return the number of microseconds this DataLine has been playing.
   */
  long getMicrosecondPosition();

  /**
   * Return true if this line is active, meaning that it is actively
   * performing audio I/O.
   */
  boolean isActive();

  /**
   * Return true if this line is running, meaning that it has been
   * started.  When the line is stopped, this method will return false.
   */
  boolean isRunning();

  /**
   * Start processing data.  This will emit a START event.
   */
  void start();

  /**
   * Stop processing data.  This will emit a STOP event.
   */
  void stop();
}