1 /*
2 * Copyright 1999-2004 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package javax.sound.sampled;
27
28
29 /**
30 * A mixer is an audio device with one or more lines. It need not be
31 * designed for mixing audio signals. A mixer that actually mixes audio
32 * has multiple input (source) lines and at least one output (target) line.
33 * The former are often instances of classes that implement
34 * <code>{@link SourceDataLine}</code>,
35 * and the latter, <code>{@link TargetDataLine}</code>. <code>{@link Port}</code>
36 * objects, too, are either source lines or target lines.
37 * A mixer can accept prerecorded, loopable sound as input, by having
38 * some of its source lines be instances of objects that implement the
39 * <code>{@link Clip}</code> interface.
40 * <p>
41 * Through methods of the <code>Line</code> interface, which <code>Mixer</code> extends,
42 * a mixer might provide a set of controls that are global to the mixer. For example,
43 * the mixer can have a master gain control. These global controls are distinct
44 * from the controls belonging to each of the mixer's individual lines.
45 * <p>
46 * Some mixers, especially
47 * those with internal digital mixing capabilities, may provide
48 * additional capabilities by implementing the <code>DataLine</code> interface.
49 * <p>
50 * A mixer can support synchronization of its lines. When one line in
51 * a synchronized group is started or stopped, the other lines in the group
52 * automatically start or stop simultaneously with the explicitly affected one.
53 *
54 * @author Kara Kytle
55 * @since 1.3
56 */
57 public interface Mixer extends Line {
58
59 /**
60 * Obtains information about this mixer, including the product's name,
61 * version, vendor, etc.
62 * @return a mixer info object that describes this mixer
63 * @see Mixer.Info
64 */
65 public Info getMixerInfo();
66
67
68 /**
69 * Obtains information about the set of source lines supported
70 * by this mixer.
71 * Some source lines may only be available when this mixer is open.
72 * @return array of <code>Line.Info</code> objects representing source lines
73 * for this mixer. If no source lines are supported,
74 * an array of length 0 is returned.
75 */
76 public Line.Info[] getSourceLineInfo();
77
78 /**
79 * Obtains information about the set of target lines supported
80 * by this mixer.
81 * Some target lines may only be available when this mixer is open.
82 * @return array of <code>Line.Info</code> objects representing target lines
83 * for this mixer. If no target lines are supported,
84 * an array of length 0 is returned.
85 */
86 public Line.Info[] getTargetLineInfo();
87
88
89 /**
90 * Obtains information about source lines of a particular type supported
91 * by the mixer.
92 * Some source lines may only be available when this mixer is open.
93 * @param info a <code>Line.Info</code> object describing lines about which information
94 * is queried
95 * @return an array of <code>Line.Info</code> objects describing source lines matching
96 * the type requested. If no matching source lines are supported, an array of length 0
97 * is returned.
98 */
99 public Line.Info[] getSourceLineInfo(Line.Info info);
100
101
102 /**
103 * Obtains information about target lines of a particular type supported
104 * by the mixer.
105 * Some target lines may only be available when this mixer is open.
106 * @param info a <code>Line.Info</code> object describing lines about which information
107 * is queried
108 * @return an array of <code>Line.Info</code> objects describing target lines matching
109 * the type requested. If no matching target lines are supported, an array of length 0
110 * is returned.
111 */
112 public Line.Info[] getTargetLineInfo(Line.Info info);
113
114
115 /**
116 * Indicates whether the mixer supports a line (or lines) that match
117 * the specified <code>Line.Info</code> object.
118 * Some lines may only be supported when this mixer is open.
119 * @param info describes the line for which support is queried
120 * @return <code>true</code> if at least one matching line is
121 * supported, <code>false</code> otherwise
122 */
123 public boolean isLineSupported(Line.Info info);
124
125 /**
126 * Obtains a line that is available for use and that matches the description
127 * in the specified <code>Line.Info</code> object.
128 *
129 * <p>If a <code>DataLine</code> is requested, and <code>info</code>
130 * is an instance of <code>DataLine.Info</code> specifying at
131 * least one fully qualified audio format, the last one
132 * will be used as the default format of the returned
133 * <code>DataLine</code>.
134 *
135 * @param info describes the desired line
136 * @throws LineUnavailableException if a matching line
137 * is not available due to resource restrictions
138 * @throws IllegalArgumentException if this mixer does
139 * not support any lines matching the description
140 * @throws SecurityException if a matching line
141 * is not available due to security restrictions
142 */
143 public Line getLine(Line.Info info) throws LineUnavailableException;
144
145 //$$fb 2002-04-12: fix for 4667258: behavior of Mixer.getMaxLines(Line.Info) method doesn't match the spec
146 /**
147 * Obtains the approximate maximum number of lines of the requested type that can be open
148 * simultaneously on the mixer.
149 *
150 * Certain types of mixers do not have a hard bound and may allow opening more lines.
151 * Since certain lines are a shared resource, a mixer may not be able to open the maximum
152 * number of lines if another process has opened lines of this mixer.
153 *
154 * The requested type is any line that matches the description in
155 * the provided <code>Line.Info</code> object. For example, if the info
156 * object represents a speaker
157 * port, and the mixer supports exactly one speaker port, this method
158 * should return 1. If the info object represents a source data line
159 * and the mixer supports the use of 32 source data lines simultaneously,
160 * the return value should be 32.
161 * If there is no limit, this function returns <code>AudioSystem.NOT_SPECIFIED</code>.
162 * @param info a <code>Line.Info</code> that describes the line for which
163 * the number of supported instances is queried
164 * @return the maximum number of matching lines supported, or <code>AudioSystem.NOT_SPECIFIED</code>
165 */
166 public int getMaxLines(Line.Info info);
167
168
169 /**
170 * Obtains the set of all source lines currently open to this mixer.
171 *
172 * @return the source lines currently open to the mixer.
173 * If no source lines are currently open to this mixer, an
174 * array of length 0 is returned.
175 * @throws SecurityException if the matching lines
176 * are not available due to security restrictions
177 */
178 public Line[] getSourceLines();
179
180 /**
181 * Obtains the set of all target lines currently open from this mixer.
182 *
183 * @return target lines currently open from the mixer.
184 * If no target lines are currently open from this mixer, an
185 * array of length 0 is returned.
186 * @throws SecurityException if the matching lines
187 * are not available due to security restrictions
188 */
189 public Line[] getTargetLines();
190
191 /**
192 * Synchronizes two or more lines. Any subsequent command that starts or stops
193 * audio playback or capture for one of these lines will exert the
194 * same effect on the other lines in the group, so that they start or stop playing or
195 * capturing data simultaneously.
196 *
197 * @param lines the lines that should be synchronized
198 * @param maintainSync <code>true</code> if the synchronization
199 * must be precisely maintained (i.e., the synchronization must be sample-accurate)
200 * at all times during operation of the lines , or <code>false</code>
201 * if precise synchronization is required only during start and stop operations
202 *
203 * @throws IllegalArgumentException if the lines cannot be synchronized.
204 * This may occur if the lines are of different types or have different
205 * formats for which this mixer does not support synchronization, or if
206 * all lines specified do not belong to this mixer.
207 */
208 public void synchronize(Line[] lines, boolean maintainSync);
209
210 /**
211 * Releases synchronization for the specified lines. The array must
212 * be identical to one for which synchronization has already been
213 * established; otherwise an exception may be thrown. However, <code>null</code>
214 * may be specified, in which case all currently synchronized lines that belong
215 * to this mixer are unsynchronized.
216 * @param lines the synchronized lines for which synchronization should be
217 * released, or <code>null</code> for all this mixer's synchronized lines
218 *
219 * @throws IllegalArgumentException if the lines cannot be unsynchronized.
220 * This may occur if the argument specified does not exactly match a set
221 * of lines for which synchronization has already been established.
222 */
223 public void unsynchronize(Line[] lines);
224
225
226 /**
227 * Reports whether this mixer supports synchronization of the specified set of lines.
228 *
229 * @param lines the set of lines for which synchronization support is queried
230 * @param maintainSync <code>true</code> if the synchronization
231 * must be precisely maintained (i.e., the synchronization must be sample-accurate)
232 * at all times during operation of the lines , or <code>false</code>
233 * if precise synchronization is required only during start and stop operations
234 *
235 * @return <code>true</code> if the lines can be synchronized, <code>false</code>
236 * otherwise
237 */
238 public boolean isSynchronizationSupported(Line[] lines, boolean maintainSync);
239
240
241 /**
242 * The <code>Mixer.Info</code> class represents information about an audio mixer,
243 * including the product's name, version, and vendor, along with a textual
244 * description. This information may be retrieved through the
245 * {@link Mixer#getMixerInfo() getMixerInfo}
246 * method of the <code>Mixer</code> interface.
247 *
248 * @author Kara Kytle
249 * @since 1.3
250 */
251 public static class Info {
252
253 /**
254 * Mixer name.
255 */
256 private /*final*/ String name;
257
258 /**
259 * Mixer vendor.
260 */
261 private /*final*/ String vendor;
262
263 /**
264 * Mixer description.
265 */
266 private /*final*/ String description;
267
268 /**
269 * Mixer version.
270 */
271 private /*final*/ String version;
272
273 /**
274 * Constructs a mixer's info object, passing it the given
275 * textual information.
276 * @param name the name of the mixer
277 * @param vendor the company who manufactures or creates the hardware
278 * or software mixer
279 * @param description descriptive text about the mixer
280 * @param version version information for the mixer
281 */
282 protected Info(String name, String vendor, String description, String version) {
283
284 this.name = name;
285 this.vendor = vendor;
286 this.description = description;
287 this.version = version;
288 }
289
290
291 /**
292 * Indicates whether two info objects are equal, returning <code>true</code> if
293 * they are identical.
294 * @param obj the reference object with which to compare this info
295 * object
296 * @return <code>true</code> if this info object is the same as the
297 * <code>obj</code> argument; <code>false</code> otherwise
298 */
299 public final boolean equals(Object obj) {
300 return super.equals(obj);
301 }
302
303 /**
304 * Finalizes the hashcode method.
305 *
306 * @return the hashcode for this object
307 */
308 public final int hashCode() {
309 return super.hashCode();
310 }
311
312 /**
313 * Obtains the name of the mixer.
314 * @return a string that names the mixer
315 */
316 public final String getName() {
317 return name;
318 }
319
320 /**
321 * Obtains the vendor of the mixer.
322 * @return a string that names the mixer's vendor
323 */
324 public final String getVendor() {
325 return vendor;
326 }
327
328 /**
329 * Obtains the description of the mixer.
330 * @return a textual description of the mixer
331 */
332 public final String getDescription() {
333 return description;
334 }
335
336 /**
337 * Obtains the version of the mixer.
338 * @return textual version information for the mixer
339 */
340 public final String getVersion() {
341 return version;
342 }
343
344 /**
345 * Provides a string representation of the mixer info.
346 * @return a string describing the info object
347 */
348 public final String toString() {
349 return (name + ", version " + version);
350 }
351 } // class Info
352 }
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