001/* An input or output line
002   Copyright (C) 2005 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package javax.sound.sampled;
040
041/**
042 * A Line represents a single input or output audio line.
043 * @since 1.3
044 */
045public interface Line
046{
047  /**
048   * An object of this type holds information about a Line.
049   * @since 1.3
050   */
051  class Info
052  {
053    private Class klass;
054
055    /**
056     * Create a new Info object.  The argument is the class of the line,
057     * for instance TargetDataLine.class.
058     * @param klass the class of the line
059     */
060    public Info(Class<?> klass)
061    {
062      this.klass = klass;
063    }
064
065    /**
066     * Return the line's class.
067     */
068    public Class<?> getLineClass()
069    {
070      return klass;
071    }
072
073    /**
074     * Return true if this Info object matches the given object.
075     * @param other the object to match
076     * @return true if they match, false otherwise
077     */
078    public boolean matches(Info other)
079    {
080      return klass.equals(other.klass);
081    }
082
083    /**
084     * Return a description of this Info object.
085     */
086    public String toString()
087    {
088      return klass.toString();
089    }
090  }
091
092  /**
093   * Add a listener which will be notified whenever this Line changes state.
094   * @param listener the listener to notify
095   */
096  void addLineListener(LineListener listener);
097
098  /**
099   * Close this line.
100   */
101  void close();
102
103  /**
104   * Return the control associated with this Line that matches the
105   * argument.
106   * @param what the type of the control to match
107   * @return the associated control
108   * @throws IllegalArgumentException if a control of this type is not
109   * available for this line
110   */
111  Control getControl(Control.Type what);
112
113  /**
114   * Return an array of controls associated with this Line.  Note that
115   * this method will not return null -- if there are no controls, it
116   * will return a zero-length array.
117   */
118  Control[] getControls();
119
120  /**
121   * Return the Info object associated with this Line.
122   */
123  Info getLineInfo();
124
125  /**
126   * Return true if a Control matching the argument is available for this
127   * Line, false otherwise.
128   * @param what the type of the control to match
129   */
130  boolean isControlSupported(Control.Type what);
131
132  /**
133   * Return true if this line is open, false otherwise.
134   */
135  boolean isOpen();
136
137  /**
138   * Open this line.
139   * @throws LineUnavailableException if the line is unavailable for some
140   * reason
141   */
142  void open() throws LineUnavailableException;
143
144  /**
145   * Remove the listener from this Line; after this call the listener will
146   * no longer be notified when this Line changes state.
147   * @param listener the listener to remove
148   */
149  void removeLineListener(LineListener listener);
150}