1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.awt.datatransfer;
27
28 import sun.datatransfer.DataFlavorUtil;
29 import sun.datatransfer.DesktopDatatransferService;
30
31 import java.io.BufferedReader;
32 import java.io.IOException;
33 import java.io.InputStream;
34 import java.io.InputStreamReader;
35 import java.lang.ref.SoftReference;
36 import java.util.ArrayList;
37 import java.util.Collections;
38 import java.util.HashMap;
39 import java.util.HashSet;
40 import java.util.LinkedHashSet;
41 import java.util.List;
42 import java.util.Map;
43 import java.util.Objects;
44 import java.util.Set;
45
46 /**
47 * The SystemFlavorMap is a configurable map between "natives" (Strings), which
48 * correspond to platform-specific data formats, and "flavors" (DataFlavors),
49 * which correspond to platform-independent MIME types. This mapping is used
50 * by the data transfer subsystem to transfer data between Java and native
51 * applications, and between Java applications in separate VMs.
52 *
53 * @since 1.2
54 */
55 public final class SystemFlavorMap implements FlavorMap, FlavorTable {
56
57 /**
58 * Constant prefix used to tag Java types converted to native platform
59 * type.
60 */
61 private static String JavaMIME = "JAVA_DATAFLAVOR:";
62
63 private static final Object FLAVOR_MAP_KEY = new Object();
64
65 /**
66 * The list of valid, decoded text flavor representation classes, in order
67 * from best to worst.
68 */
69 private static final String[] UNICODE_TEXT_CLASSES = {
70 "java.io.Reader", "java.lang.String", "java.nio.CharBuffer", "\"[C\""
71 };
72
73 /**
74 * The list of valid, encoded text flavor representation classes, in order
75 * from best to worst.
76 */
77 private static final String[] ENCODED_TEXT_CLASSES = {
78 "java.io.InputStream", "java.nio.ByteBuffer", "\"[B\""
79 };
80
81 /**
82 * A String representing text/plain MIME type.
83 */
84 private static final String TEXT_PLAIN_BASE_TYPE = "text/plain";
85
86 /**
87 * A String representing text/html MIME type.
88 */
89 private static final String HTML_TEXT_BASE_TYPE = "text/html";
90
91 /**
92 * Maps native Strings to Lists of DataFlavors (or base type Strings for
93 * text DataFlavors).
94 * Do not use the field directly, use getNativeToFlavor() instead.
95 */
96 private final Map<String, LinkedHashSet<DataFlavor>> nativeToFlavor = new HashMap<>();
97
98 /**
99 * Accessor to nativeToFlavor map. Since we use lazy initialization we must
100 * use this accessor instead of direct access to the field which may not be
101 * initialized yet. This method will initialize the field if needed.
102 *
103 * @return nativeToFlavor
104 */
105 private Map<String, LinkedHashSet<DataFlavor>> getNativeToFlavor() {
106 if (!isMapInitialized) {
107 initSystemFlavorMap();
108 }
109 return nativeToFlavor;
110 }
111
112 /**
113 * Maps DataFlavors (or base type Strings for text DataFlavors) to Lists of
114 * native Strings.
115 * Do not use the field directly, use getFlavorToNative() instead.
116 */
117 private final Map<DataFlavor, LinkedHashSet<String>> flavorToNative = new HashMap<>();
118
119 /**
120 * Accessor to flavorToNative map. Since we use lazy initialization we must
121 * use this accessor instead of direct access to the field which may not be
122 * initialized yet. This method will initialize the field if needed.
123 *
124 * @return flavorToNative
125 */
126 private synchronized Map<DataFlavor, LinkedHashSet<String>> getFlavorToNative() {
127 if (!isMapInitialized) {
128 initSystemFlavorMap();
129 }
130 return flavorToNative;
131 }
132
133 /**
134 * Maps a text DataFlavor primary mime-type to the native. Used only to store
135 * standard mappings registered in the flavormap.properties
136 * Do not use this field directly, use getTextTypeToNative() instead.
137 */
138 private Map<String, LinkedHashSet<String>> textTypeToNative = new HashMap<>();
139
140 /**
141 * Shows if the object has been initialized.
142 */
143 private boolean isMapInitialized = false;
144
145 /**
146 * An accessor to textTypeToNative map. Since we use lazy initialization we
147 * must use this accessor instead of direct access to the field which may not
148 * be initialized yet. This method will initialize the field if needed.
149 *
150 * @return textTypeToNative
151 */
152 private synchronized Map<String, LinkedHashSet<String>> getTextTypeToNative() {
153 if (!isMapInitialized) {
154 initSystemFlavorMap();
155 // From this point the map should not be modified
156 textTypeToNative = Collections.unmodifiableMap(textTypeToNative);
157 }
158 return textTypeToNative;
159 }
160
161 /**
162 * Caches the result of getNativesForFlavor(). Maps DataFlavors to
163 * SoftReferences which reference LinkedHashSet of String natives.
164 */
165 private final SoftCache<DataFlavor, String> nativesForFlavorCache = new SoftCache<>();
166
167 /**
168 * Caches the result getFlavorsForNative(). Maps String natives to
169 * SoftReferences which reference LinkedHashSet of DataFlavors.
170 */
171 private final SoftCache<String, DataFlavor> flavorsForNativeCache = new SoftCache<>();
172
173 /**
174 * Dynamic mapping generation used for text mappings should not be applied
175 * to the DataFlavors and String natives for which the mappings have been
176 * explicitly specified with setFlavorsForNative() or
177 * setNativesForFlavor(). This keeps all such keys.
178 */
179 private Set<Object> disabledMappingGenerationKeys = new HashSet<>();
180
181 /**
182 * Returns the default FlavorMap for this thread's ClassLoader.
183 *
184 * @return the default FlavorMap for this thread's ClassLoader
185 */
186 public static FlavorMap getDefaultFlavorMap() {
187 return DataFlavorUtil.getDesktopService().getFlavorMap(SystemFlavorMap::new);
188 }
189
190 private SystemFlavorMap() {
191 }
192
193 /**
194 * Initializes a SystemFlavorMap by reading flavormap.properties
195 * For thread-safety must be called under lock on this.
196 */
197 private void initSystemFlavorMap() {
198 if (isMapInitialized) {
199 return;
200 }
201 isMapInitialized = true;
202
203 InputStream is = SystemFlavorMap.class.getResourceAsStream("/sun/datatransfer/resources/flavormap.properties");
204 if (is == null) {
205 throw new InternalError("Default flavor mapping not found");
206 }
207
208 try (InputStreamReader isr = new InputStreamReader(is);
209 BufferedReader reader = new BufferedReader(isr)) {
210 String line;
211 while ((line = reader.readLine()) != null) {
212 line = line.trim();
213 if (line.startsWith("#") || line.isEmpty()) continue;
214 while (line.endsWith("\\")) {
215 line = line.substring(0, line.length() - 1) + reader.readLine().trim();
216 }
217 int delimiterPosition = line.indexOf('=');
218 String key = line.substring(0, delimiterPosition).replaceAll("\\ ", " ");
219 String[] values = line.substring(delimiterPosition + 1, line.length()).split(",");
220 for (String value : values) {
221 try {
222 value = loadConvert(value);
223 MimeType mime = new MimeType(value);
224 if ("text".equals(mime.getPrimaryType())) {
225 String charset = mime.getParameter("charset");
226 if (DataFlavorUtil.doesSubtypeSupportCharset(mime.getSubType(), charset))
227 {
228 // We need to store the charset and eoln
229 // parameters, if any, so that the
230 // DataTransferer will have this information
231 // for conversion into the native format.
232 DesktopDatatransferService desktopService =
233 DataFlavorUtil.getDesktopService();
234 if (desktopService.isDesktopPresent()) {
235 desktopService.registerTextFlavorProperties(
236 key, charset,
237 mime.getParameter("eoln"),
238 mime.getParameter("terminators"));
239 }
240 }
241
242 // But don't store any of these parameters in the
243 // DataFlavor itself for any text natives (even
244 // non-charset ones). The SystemFlavorMap will
245 // synthesize the appropriate mappings later.
246 mime.removeParameter("charset");
247 mime.removeParameter("class");
248 mime.removeParameter("eoln");
249 mime.removeParameter("terminators");
250 value = mime.toString();
251 }
252 } catch (MimeTypeParseException e) {
253 e.printStackTrace();
254 continue;
255 }
256
257 DataFlavor flavor;
258 try {
259 flavor = new DataFlavor(value);
260 } catch (Exception e) {
261 try {
262 flavor = new DataFlavor(value, null);
263 } catch (Exception ee) {
264 ee.printStackTrace();
265 continue;
266 }
267 }
268
269 final LinkedHashSet<DataFlavor> dfs = new LinkedHashSet<>();
270 dfs.add(flavor);
271
272 if ("text".equals(flavor.getPrimaryType())) {
273 dfs.addAll(convertMimeTypeToDataFlavors(value));
274 store(flavor.mimeType.getBaseType(), key, getTextTypeToNative());
275 }
276
277 for (DataFlavor df : dfs) {
278 store(df, key, getFlavorToNative());
279 store(key, df, getNativeToFlavor());
280 }
281 }
282 }
283 } catch (IOException e) {
284 throw new InternalError("Error reading default flavor mapping", e);
285 }
286 }
287
288 // Copied from java.util.Properties
289 private static String loadConvert(String theString) {
290 char aChar;
291 int len = theString.length();
292 StringBuilder outBuffer = new StringBuilder(len);
293
294 for (int x = 0; x < len; ) {
295 aChar = theString.charAt(x++);
296 if (aChar == '\\') {
297 aChar = theString.charAt(x++);
298 if (aChar == 'u') {
299 // Read the xxxx
300 int value = 0;
301 for (int i = 0; i < 4; i++) {
302 aChar = theString.charAt(x++);
303 switch (aChar) {
304 case '0': case '1': case '2': case '3': case '4':
305 case '5': case '6': case '7': case '8': case '9': {
306 value = (value << 4) + aChar - '0';
307 break;
308 }
309 case 'a': case 'b': case 'c':
310 case 'd': case 'e': case 'f': {
311 value = (value << 4) + 10 + aChar - 'a';
312 break;
313 }
314 case 'A': case 'B': case 'C':
315 case 'D': case 'E': case 'F': {
316 value = (value << 4) + 10 + aChar - 'A';
317 break;
318 }
319 default: {
320 throw new IllegalArgumentException(
321 "Malformed \\uxxxx encoding.");
322 }
323 }
324 }
325 outBuffer.append((char)value);
326 } else {
327 if (aChar == 't') {
328 aChar = '\t';
329 } else if (aChar == 'r') {
330 aChar = '\r';
331 } else if (aChar == 'n') {
332 aChar = '\n';
333 } else if (aChar == 'f') {
334 aChar = '\f';
335 }
336 outBuffer.append(aChar);
337 }
338 } else {
339 outBuffer.append(aChar);
340 }
341 }
342 return outBuffer.toString();
343 }
344
345 /**
346 * Stores the listed object under the specified hash key in map. Unlike a
347 * standard map, the listed object will not replace any object already at
348 * the appropriate Map location, but rather will be appended to a List
349 * stored in that location.
350 */
351 private <H, L> void store(H hashed, L listed, Map<H, LinkedHashSet<L>> map) {
352 LinkedHashSet<L> list = map.get(hashed);
353 if (list == null) {
354 list = new LinkedHashSet<>(1);
355 map.put(hashed, list);
356 }
357 if (!list.contains(listed)) {
358 list.add(listed);
359 }
360 }
361
362 /**
363 * Semantically equivalent to 'nativeToFlavor.get(nat)'. This method
364 * handles the case where 'nat' is not found in 'nativeToFlavor'. In that
365 * case, a new DataFlavor is synthesized, stored, and returned, if and
366 * only if the specified native is encoded as a Java MIME type.
367 */
368 private LinkedHashSet<DataFlavor> nativeToFlavorLookup(String nat) {
369 LinkedHashSet<DataFlavor> flavors = getNativeToFlavor().get(nat);
370
371 if (nat != null && !disabledMappingGenerationKeys.contains(nat)) {
372 DesktopDatatransferService desktopService = DataFlavorUtil.getDesktopService();
373 if (desktopService.isDesktopPresent()) {
374 LinkedHashSet<DataFlavor> platformFlavors =
375 desktopService.getPlatformMappingsForNative(nat);
376 if (!platformFlavors.isEmpty()) {
377 if (flavors != null) {
378 // Prepending the platform-specific mappings ensures
379 // that the flavors added with
380 // addFlavorForUnencodedNative() are at the end of
381 // list.
382 platformFlavors.addAll(flavors);
383 }
384 flavors = platformFlavors;
385 }
386 }
387 }
388
389 if (flavors == null && isJavaMIMEType(nat)) {
390 String decoded = decodeJavaMIMEType(nat);
391 DataFlavor flavor = null;
392
393 try {
394 flavor = new DataFlavor(decoded);
395 } catch (Exception e) {
396 System.err.println("Exception \"" + e.getClass().getName() +
397 ": " + e.getMessage() +
398 "\"while constructing DataFlavor for: " +
399 decoded);
400 }
401
402 if (flavor != null) {
403 flavors = new LinkedHashSet<>(1);
404 getNativeToFlavor().put(nat, flavors);
405 flavors.add(flavor);
406 flavorsForNativeCache.remove(nat);
407
408 LinkedHashSet<String> natives = getFlavorToNative().get(flavor);
409 if (natives == null) {
410 natives = new LinkedHashSet<>(1);
411 getFlavorToNative().put(flavor, natives);
412 }
413 natives.add(nat);
414 nativesForFlavorCache.remove(flavor);
415 }
416 }
417
418 return (flavors != null) ? flavors : new LinkedHashSet<>(0);
419 }
420
421 /**
422 * Semantically equivalent to 'flavorToNative.get(flav)'. This method
423 * handles the case where 'flav' is not found in 'flavorToNative' depending
424 * on the value of passes 'synthesize' parameter. If 'synthesize' is
425 * SYNTHESIZE_IF_NOT_FOUND a native is synthesized, stored, and returned by
426 * encoding the DataFlavor's MIME type. Otherwise an empty List is returned
427 * and 'flavorToNative' remains unaffected.
428 */
429 private LinkedHashSet<String> flavorToNativeLookup(final DataFlavor flav,
430 final boolean synthesize) {
431
432 LinkedHashSet<String> natives = getFlavorToNative().get(flav);
433
434 if (flav != null && !disabledMappingGenerationKeys.contains(flav)) {
435 DesktopDatatransferService desktopService = DataFlavorUtil.getDesktopService();
436 if (desktopService.isDesktopPresent()) {
437 LinkedHashSet<String> platformNatives =
438 desktopService.getPlatformMappingsForFlavor(flav);
439 if (!platformNatives.isEmpty()) {
440 if (natives != null) {
441 // Prepend the platform-specific mappings to ensure
442 // that the natives added with
443 // addUnencodedNativeForFlavor() are at the end of
444 // list.
445 platformNatives.addAll(natives);
446 }
447 natives = platformNatives;
448 }
449 }
450 }
451
452 if (natives == null) {
453 if (synthesize) {
454 String encoded = encodeDataFlavor(flav);
455 natives = new LinkedHashSet<>(1);
456 getFlavorToNative().put(flav, natives);
457 natives.add(encoded);
458
459 LinkedHashSet<DataFlavor> flavors = getNativeToFlavor().get(encoded);
460 if (flavors == null) {
461 flavors = new LinkedHashSet<>(1);
462 getNativeToFlavor().put(encoded, flavors);
463 }
464 flavors.add(flav);
465
466 nativesForFlavorCache.remove(flav);
467 flavorsForNativeCache.remove(encoded);
468 } else {
469 natives = new LinkedHashSet<>(0);
470 }
471 }
472
473 return new LinkedHashSet<>(natives);
474 }
475
476 /**
477 * Returns a <code>List</code> of <code>String</code> natives to which the
478 * specified <code>DataFlavor</code> can be translated by the data transfer
479 * subsystem. The <code>List</code> will be sorted from best native to
480 * worst. That is, the first native will best reflect data in the specified
481 * flavor to the underlying native platform.
482 * <p>
483 * If the specified <code>DataFlavor</code> is previously unknown to the
484 * data transfer subsystem and the data transfer subsystem is unable to
485 * translate this <code>DataFlavor</code> to any existing native, then
486 * invoking this method will establish a
487 * mapping in both directions between the specified <code>DataFlavor</code>
488 * and an encoded version of its MIME type as its native.
489 *
490 * @param flav the <code>DataFlavor</code> whose corresponding natives
491 * should be returned. If <code>null</code> is specified, all
492 * natives currently known to the data transfer subsystem are
493 * returned in a non-deterministic order.
494 * @return a <code>java.util.List</code> of <code>java.lang.String</code>
495 * objects which are platform-specific representations of platform-
496 * specific data formats
497 *
498 * @see #encodeDataFlavor
499 * @since 1.4
500 */
501 @Override
502 public synchronized List<String> getNativesForFlavor(DataFlavor flav) {
503 LinkedHashSet<String> retval = nativesForFlavorCache.check(flav);
504 if (retval != null) {
505 return new ArrayList<>(retval);
506 }
507
508 if (flav == null) {
509 retval = new LinkedHashSet<>(getNativeToFlavor().keySet());
510 } else if (disabledMappingGenerationKeys.contains(flav)) {
511 // In this case we shouldn't synthesize a native for this flavor,
512 // since its mappings were explicitly specified.
513 retval = flavorToNativeLookup(flav, false);
514 } else if (DataFlavorUtil.isFlavorCharsetTextType(flav)) {
515 retval = new LinkedHashSet<>(0);
516
517 // For text/* flavors, flavor-to-native mappings specified in
518 // flavormap.properties are stored per flavor's base type.
519 if ("text".equals(flav.getPrimaryType())) {
520 LinkedHashSet<String> textTypeNatives =
521 getTextTypeToNative().get(flav.mimeType.getBaseType());
522 if (textTypeNatives != null) {
523 retval.addAll(textTypeNatives);
524 }
525 }
526
527 // Also include text/plain natives, but don't duplicate Strings
528 LinkedHashSet<String> textTypeNatives =
529 getTextTypeToNative().get(TEXT_PLAIN_BASE_TYPE);
530 if (textTypeNatives != null) {
531 retval.addAll(textTypeNatives);
532 }
533
534 if (retval.isEmpty()) {
535 retval = flavorToNativeLookup(flav, true);
536 } else {
537 // In this branch it is guaranteed that natives explicitly
538 // listed for flav's MIME type were added with
539 // addUnencodedNativeForFlavor(), so they have lower priority.
540 retval.addAll(flavorToNativeLookup(flav, false));
541 }
542 } else if (DataFlavorUtil.isFlavorNoncharsetTextType(flav)) {
543 retval = getTextTypeToNative().get(flav.mimeType.getBaseType());
544
545 if (retval == null || retval.isEmpty()) {
546 retval = flavorToNativeLookup(flav, true);
547 } else {
548 // In this branch it is guaranteed that natives explicitly
549 // listed for flav's MIME type were added with
550 // addUnencodedNativeForFlavor(), so they have lower priority.
551 retval.addAll(flavorToNativeLookup(flav, false));
552 }
553 } else {
554 retval = flavorToNativeLookup(flav, true);
555 }
556
557 nativesForFlavorCache.put(flav, retval);
558 // Create a copy, because client code can modify the returned list.
559 return new ArrayList<>(retval);
560 }
561
562 /**
563 * Returns a <code>List</code> of <code>DataFlavor</code>s to which the
564 * specified <code>String</code> native can be translated by the data
565 * transfer subsystem. The <code>List</code> will be sorted from best
566 * <code>DataFlavor</code> to worst. That is, the first
567 * <code>DataFlavor</code> will best reflect data in the specified
568 * native to a Java application.
569 * <p>
570 * If the specified native is previously unknown to the data transfer
571 * subsystem, and that native has been properly encoded, then invoking this
572 * method will establish a mapping in both directions between the specified
573 * native and a <code>DataFlavor</code> whose MIME type is a decoded
574 * version of the native.
575 * <p>
576 * If the specified native is not a properly encoded native and the
577 * mappings for this native have not been altered with
578 * <code>setFlavorsForNative</code>, then the contents of the
579 * <code>List</code> is platform dependent, but <code>null</code>
580 * cannot be returned.
581 *
582 * @param nat the native whose corresponding <code>DataFlavor</code>s
583 * should be returned. If <code>null</code> is specified, all
584 * <code>DataFlavor</code>s currently known to the data transfer
585 * subsystem are returned in a non-deterministic order.
586 * @return a <code>java.util.List</code> of <code>DataFlavor</code>
587 * objects into which platform-specific data in the specified,
588 * platform-specific native can be translated
589 *
590 * @see #encodeJavaMIMEType
591 * @since 1.4
592 */
593 @Override
594 public synchronized List<DataFlavor> getFlavorsForNative(String nat) {
595 LinkedHashSet<DataFlavor> returnValue = flavorsForNativeCache.check(nat);
596 if (returnValue != null) {
597 return new ArrayList<>(returnValue);
598 } else {
599 returnValue = new LinkedHashSet<>();
600 }
601
602 if (nat == null) {
603 for (String n : getNativesForFlavor(null)) {
604 returnValue.addAll(getFlavorsForNative(n));
605 }
606 } else {
607 final LinkedHashSet<DataFlavor> flavors = nativeToFlavorLookup(nat);
608 if (disabledMappingGenerationKeys.contains(nat)) {
609 return new ArrayList<>(flavors);
610 }
611
612 final LinkedHashSet<DataFlavor> flavorsWithSynthesized =
613 nativeToFlavorLookup(nat);
614
615 for (DataFlavor df : flavorsWithSynthesized) {
616 returnValue.add(df);
617 if ("text".equals(df.getPrimaryType())) {
618 String baseType = df.mimeType.getBaseType();
619 returnValue.addAll(convertMimeTypeToDataFlavors(baseType));
620 }
621 }
622 }
623 flavorsForNativeCache.put(nat, returnValue);
624 return new ArrayList<>(returnValue);
625 }
626
627 private static Set<DataFlavor> convertMimeTypeToDataFlavors(
628 final String baseType) {
629
630 final Set<DataFlavor> returnValue = new LinkedHashSet<>();
631
632 String subType = null;
633
634 try {
635 final MimeType mimeType = new MimeType(baseType);
636 subType = mimeType.getSubType();
637 } catch (MimeTypeParseException mtpe) {
638 // Cannot happen, since we checked all mappings
639 // on load from flavormap.properties.
640 }
641
642 if (DataFlavorUtil.doesSubtypeSupportCharset(subType, null)) {
643 if (TEXT_PLAIN_BASE_TYPE.equals(baseType))
644 {
645 returnValue.add(DataFlavor.stringFlavor);
646 }
647
648 for (String unicodeClassName : UNICODE_TEXT_CLASSES) {
649 final String mimeType = baseType + ";charset=Unicode;class=" +
650 unicodeClassName;
651
652 final LinkedHashSet<String> mimeTypes =
653 handleHtmlMimeTypes(baseType, mimeType);
654 for (String mt : mimeTypes) {
655 DataFlavor toAdd = null;
656 try {
657 toAdd = new DataFlavor(mt);
658 } catch (ClassNotFoundException cannotHappen) {
659 }
660 returnValue.add(toAdd);
661 }
662 }
663
664 for (String charset : DataFlavorUtil.standardEncodings()) {
665
666 for (String encodedTextClass : ENCODED_TEXT_CLASSES) {
667 final String mimeType =
668 baseType + ";charset=" + charset +
669 ";class=" + encodedTextClass;
670
671 final LinkedHashSet<String> mimeTypes =
672 handleHtmlMimeTypes(baseType, mimeType);
673
674 for (String mt : mimeTypes) {
675
676 DataFlavor df = null;
677
678 try {
679 df = new DataFlavor(mt);
680 // Check for equality to plainTextFlavor so
681 // that we can ensure that the exact charset of
682 // plainTextFlavor, not the canonical charset
683 // or another equivalent charset with a
684 // different name, is used.
685 if (df.equals(DataFlavor.plainTextFlavor)) {
686 df = DataFlavor.plainTextFlavor;
687 }
688 } catch (ClassNotFoundException cannotHappen) {
689 }
690
691 returnValue.add(df);
692 }
693 }
694 }
695
696 if (TEXT_PLAIN_BASE_TYPE.equals(baseType))
697 {
698 returnValue.add(DataFlavor.plainTextFlavor);
699 }
700 } else {
701 // Non-charset text natives should be treated as
702 // opaque, 8-bit data in any of its various
703 // representations.
704 for (String encodedTextClassName : ENCODED_TEXT_CLASSES) {
705 DataFlavor toAdd = null;
706 try {
707 toAdd = new DataFlavor(baseType +
708 ";class=" + encodedTextClassName);
709 } catch (ClassNotFoundException cannotHappen) {
710 }
711 returnValue.add(toAdd);
712 }
713 }
714 return returnValue;
715 }
716
717 private static final String [] htmlDocumntTypes =
718 new String [] {"all", "selection", "fragment"};
719
720 private static LinkedHashSet<String> handleHtmlMimeTypes(String baseType,
721 String mimeType) {
722
723 LinkedHashSet<String> returnValues = new LinkedHashSet<>();
724
725 if (HTML_TEXT_BASE_TYPE.equals(baseType)) {
726 for (String documentType : htmlDocumntTypes) {
727 returnValues.add(mimeType + ";document=" + documentType);
728 }
729 } else {
730 returnValues.add(mimeType);
731 }
732
733 return returnValues;
734 }
735
736 /**
737 * Returns a <code>Map</code> of the specified <code>DataFlavor</code>s to
738 * their most preferred <code>String</code> native. Each native value will
739 * be the same as the first native in the List returned by
740 * <code>getNativesForFlavor</code> for the specified flavor.
741 * <p>
742 * If a specified <code>DataFlavor</code> is previously unknown to the
743 * data transfer subsystem, then invoking this method will establish a
744 * mapping in both directions between the specified <code>DataFlavor</code>
745 * and an encoded version of its MIME type as its native.
746 *
747 * @param flavors an array of <code>DataFlavor</code>s which will be the
748 * key set of the returned <code>Map</code>. If <code>null</code> is
749 * specified, a mapping of all <code>DataFlavor</code>s known to the
750 * data transfer subsystem to their most preferred
751 * <code>String</code> natives will be returned.
752 * @return a <code>java.util.Map</code> of <code>DataFlavor</code>s to
753 * <code>String</code> natives
754 *
755 * @see #getNativesForFlavor
756 * @see #encodeDataFlavor
757 */
758 @Override
759 public synchronized Map<DataFlavor,String> getNativesForFlavors(DataFlavor[] flavors)
760 {
761 // Use getNativesForFlavor to generate extra natives for text flavors
762 // and stringFlavor
763
764 if (flavors == null) {
765 List<DataFlavor> flavor_list = getFlavorsForNative(null);
766 flavors = new DataFlavor[flavor_list.size()];
767 flavor_list.toArray(flavors);
768 }
769
770 Map<DataFlavor, String> retval = new HashMap<>(flavors.length, 1.0f);
771 for (DataFlavor flavor : flavors) {
772 List<String> natives = getNativesForFlavor(flavor);
773 String nat = (natives.isEmpty()) ? null : natives.get(0);
774 retval.put(flavor, nat);
775 }
776
777 return retval;
778 }
779
780 /**
781 * Returns a <code>Map</code> of the specified <code>String</code> natives
782 * to their most preferred <code>DataFlavor</code>. Each
783 * <code>DataFlavor</code> value will be the same as the first
784 * <code>DataFlavor</code> in the List returned by
785 * <code>getFlavorsForNative</code> for the specified native.
786 * <p>
787 * If a specified native is previously unknown to the data transfer
788 * subsystem, and that native has been properly encoded, then invoking this
789 * method will establish a mapping in both directions between the specified
790 * native and a <code>DataFlavor</code> whose MIME type is a decoded
791 * version of the native.
792 *
793 * @param natives an array of <code>String</code>s which will be the
794 * key set of the returned <code>Map</code>. If <code>null</code> is
795 * specified, a mapping of all supported <code>String</code> natives
796 * to their most preferred <code>DataFlavor</code>s will be
797 * returned.
798 * @return a <code>java.util.Map</code> of <code>String</code> natives to
799 * <code>DataFlavor</code>s
800 *
801 * @see #getFlavorsForNative
802 * @see #encodeJavaMIMEType
803 */
804 @Override
805 public synchronized Map<String,DataFlavor> getFlavorsForNatives(String[] natives)
806 {
807 // Use getFlavorsForNative to generate extra flavors for text natives
808 if (natives == null) {
809 List<String> nativesList = getNativesForFlavor(null);
810 natives = new String[nativesList.size()];
811 nativesList.toArray(natives);
812 }
813
814 Map<String, DataFlavor> retval = new HashMap<>(natives.length, 1.0f);
815 for (String aNative : natives) {
816 List<DataFlavor> flavors = getFlavorsForNative(aNative);
817 DataFlavor flav = (flavors.isEmpty())? null : flavors.get(0);
818 retval.put(aNative, flav);
819 }
820 return retval;
821 }
822
823 /**
824 * Adds a mapping from the specified <code>DataFlavor</code> (and all
825 * <code>DataFlavor</code>s equal to the specified <code>DataFlavor</code>)
826 * to the specified <code>String</code> native.
827 * Unlike <code>getNativesForFlavor</code>, the mapping will only be
828 * established in one direction, and the native will not be encoded. To
829 * establish a two-way mapping, call
830 * <code>addFlavorForUnencodedNative</code> as well. The new mapping will
831 * be of lower priority than any existing mapping.
832 * This method has no effect if a mapping from the specified or equal
833 * <code>DataFlavor</code> to the specified <code>String</code> native
834 * already exists.
835 *
836 * @param flav the <code>DataFlavor</code> key for the mapping
837 * @param nat the <code>String</code> native value for the mapping
838 * @throws NullPointerException if flav or nat is <code>null</code>
839 *
840 * @see #addFlavorForUnencodedNative
841 * @since 1.4
842 */
843 public synchronized void addUnencodedNativeForFlavor(DataFlavor flav,
844 String nat) {
845 Objects.requireNonNull(nat, "Null native not permitted");
846 Objects.requireNonNull(flav, "Null flavor not permitted");
847
848 LinkedHashSet<String> natives = getFlavorToNative().get(flav);
849 if (natives == null) {
850 natives = new LinkedHashSet<>(1);
851 getFlavorToNative().put(flav, natives);
852 }
853 natives.add(nat);
854 nativesForFlavorCache.remove(flav);
855 }
856
857 /**
858 * Discards the current mappings for the specified <code>DataFlavor</code>
859 * and all <code>DataFlavor</code>s equal to the specified
860 * <code>DataFlavor</code>, and creates new mappings to the
861 * specified <code>String</code> natives.
862 * Unlike <code>getNativesForFlavor</code>, the mappings will only be
863 * established in one direction, and the natives will not be encoded. To
864 * establish two-way mappings, call <code>setFlavorsForNative</code>
865 * as well. The first native in the array will represent the highest
866 * priority mapping. Subsequent natives will represent mappings of
867 * decreasing priority.
868 * <p>
869 * If the array contains several elements that reference equal
870 * <code>String</code> natives, this method will establish new mappings
871 * for the first of those elements and ignore the rest of them.
872 * <p>
873 * It is recommended that client code not reset mappings established by the
874 * data transfer subsystem. This method should only be used for
875 * application-level mappings.
876 *
877 * @param flav the <code>DataFlavor</code> key for the mappings
878 * @param natives the <code>String</code> native values for the mappings
879 * @throws NullPointerException if flav or natives is <code>null</code>
880 * or if natives contains <code>null</code> elements
881 *
882 * @see #setFlavorsForNative
883 * @since 1.4
884 */
885 public synchronized void setNativesForFlavor(DataFlavor flav,
886 String[] natives) {
887 Objects.requireNonNull(natives, "Null natives not permitted");
888 Objects.requireNonNull(flav, "Null flavors not permitted");
889
890 getFlavorToNative().remove(flav);
891 for (String aNative : natives) {
892 addUnencodedNativeForFlavor(flav, aNative);
893 }
894 disabledMappingGenerationKeys.add(flav);
895 nativesForFlavorCache.remove(flav);
896 }
897
898 /**
899 * Adds a mapping from a single <code>String</code> native to a single
900 * <code>DataFlavor</code>. Unlike <code>getFlavorsForNative</code>, the
901 * mapping will only be established in one direction, and the native will
902 * not be encoded. To establish a two-way mapping, call
903 * <code>addUnencodedNativeForFlavor</code> as well. The new mapping will
904 * be of lower priority than any existing mapping.
905 * This method has no effect if a mapping from the specified
906 * <code>String</code> native to the specified or equal
907 * <code>DataFlavor</code> already exists.
908 *
909 * @param nat the <code>String</code> native key for the mapping
910 * @param flav the <code>DataFlavor</code> value for the mapping
911 * @throws NullPointerException if nat or flav is <code>null</code>
912 *
913 * @see #addUnencodedNativeForFlavor
914 * @since 1.4
915 */
916 public synchronized void addFlavorForUnencodedNative(String nat,
917 DataFlavor flav) {
918 Objects.requireNonNull(nat, "Null native not permitted");
919 Objects.requireNonNull(flav, "Null flavor not permitted");
920
921 LinkedHashSet<DataFlavor> flavors = getNativeToFlavor().get(nat);
922 if (flavors == null) {
923 flavors = new LinkedHashSet<>(1);
924 getNativeToFlavor().put(nat, flavors);
925 }
926 flavors.add(flav);
927 flavorsForNativeCache.remove(nat);
928 }
929
930 /**
931 * Discards the current mappings for the specified <code>String</code>
932 * native, and creates new mappings to the specified
933 * <code>DataFlavor</code>s. Unlike <code>getFlavorsForNative</code>, the
934 * mappings will only be established in one direction, and the natives need
935 * not be encoded. To establish two-way mappings, call
936 * <code>setNativesForFlavor</code> as well. The first
937 * <code>DataFlavor</code> in the array will represent the highest priority
938 * mapping. Subsequent <code>DataFlavor</code>s will represent mappings of
939 * decreasing priority.
940 * <p>
941 * If the array contains several elements that reference equal
942 * <code>DataFlavor</code>s, this method will establish new mappings
943 * for the first of those elements and ignore the rest of them.
944 * <p>
945 * It is recommended that client code not reset mappings established by the
946 * data transfer subsystem. This method should only be used for
947 * application-level mappings.
948 *
949 * @param nat the <code>String</code> native key for the mappings
950 * @param flavors the <code>DataFlavor</code> values for the mappings
951 * @throws NullPointerException if nat or flavors is <code>null</code>
952 * or if flavors contains <code>null</code> elements
953 *
954 * @see #setNativesForFlavor
955 * @since 1.4
956 */
957 public synchronized void setFlavorsForNative(String nat,
958 DataFlavor[] flavors) {
959 Objects.requireNonNull(nat, "Null native not permitted");
960 Objects.requireNonNull(flavors, "Null flavors not permitted");
961
962 getNativeToFlavor().remove(nat);
963 for (DataFlavor flavor : flavors) {
964 addFlavorForUnencodedNative(nat, flavor);
965 }
966 disabledMappingGenerationKeys.add(nat);
967 flavorsForNativeCache.remove(nat);
968 }
969
970 /**
971 * Encodes a MIME type for use as a <code>String</code> native. The format
972 * of an encoded representation of a MIME type is implementation-dependent.
973 * The only restrictions are:
974 * <ul>
975 * <li>The encoded representation is <code>null</code> if and only if the
976 * MIME type <code>String</code> is <code>null</code>.</li>
977 * <li>The encoded representations for two non-<code>null</code> MIME type
978 * <code>String</code>s are equal if and only if these <code>String</code>s
979 * are equal according to <code>String.equals(Object)</code>.</li>
980 * </ul>
981 * <p>
982 * The reference implementation of this method returns the specified MIME
983 * type <code>String</code> prefixed with <code>JAVA_DATAFLAVOR:</code>.
984 *
985 * @param mimeType the MIME type to encode
986 * @return the encoded <code>String</code>, or <code>null</code> if
987 * mimeType is <code>null</code>
988 */
989 public static String encodeJavaMIMEType(String mimeType) {
990 return (mimeType != null)
991 ? JavaMIME + mimeType
992 : null;
993 }
994
995 /**
996 * Encodes a <code>DataFlavor</code> for use as a <code>String</code>
997 * native. The format of an encoded <code>DataFlavor</code> is
998 * implementation-dependent. The only restrictions are:
999 * <ul>
1000 * <li>The encoded representation is <code>null</code> if and only if the
1001 * specified <code>DataFlavor</code> is <code>null</code> or its MIME type
1002 * <code>String</code> is <code>null</code>.</li>
1003 * <li>The encoded representations for two non-<code>null</code>
1004 * <code>DataFlavor</code>s with non-<code>null</code> MIME type
1005 * <code>String</code>s are equal if and only if the MIME type
1006 * <code>String</code>s of these <code>DataFlavor</code>s are equal
1007 * according to <code>String.equals(Object)</code>.</li>
1008 * </ul>
1009 * <p>
1010 * The reference implementation of this method returns the MIME type
1011 * <code>String</code> of the specified <code>DataFlavor</code> prefixed
1012 * with <code>JAVA_DATAFLAVOR:</code>.
1013 *
1014 * @param flav the <code>DataFlavor</code> to encode
1015 * @return the encoded <code>String</code>, or <code>null</code> if
1016 * flav is <code>null</code> or has a <code>null</code> MIME type
1017 */
1018 public static String encodeDataFlavor(DataFlavor flav) {
1019 return (flav != null)
1020 ? SystemFlavorMap.encodeJavaMIMEType(flav.getMimeType())
1021 : null;
1022 }
1023
1024 /**
1025 * Returns whether the specified <code>String</code> is an encoded Java
1026 * MIME type.
1027 *
1028 * @param str the <code>String</code> to test
1029 * @return <code>true</code> if the <code>String</code> is encoded;
1030 * <code>false</code> otherwise
1031 */
1032 public static boolean isJavaMIMEType(String str) {
1033 return (str != null && str.startsWith(JavaMIME, 0));
1034 }
1035
1036 /**
1037 * Decodes a <code>String</code> native for use as a Java MIME type.
1038 *
1039 * @param nat the <code>String</code> to decode
1040 * @return the decoded Java MIME type, or <code>null</code> if nat is not
1041 * an encoded <code>String</code> native
1042 */
1043 public static String decodeJavaMIMEType(String nat) {
1044 return (isJavaMIMEType(nat))
1045 ? nat.substring(JavaMIME.length(), nat.length()).trim()
1046 : null;
1047 }
1048
1049 /**
1050 * Decodes a <code>String</code> native for use as a
1051 * <code>DataFlavor</code>.
1052 *
1053 * @param nat the <code>String</code> to decode
1054 * @return the decoded <code>DataFlavor</code>, or <code>null</code> if
1055 * nat is not an encoded <code>String</code> native
1056 * @throws ClassNotFoundException if the class of the data flavor
1057 * is not loaded
1058 */
1059 public static DataFlavor decodeDataFlavor(String nat)
1060 throws ClassNotFoundException
1061 {
1062 String retval_str = SystemFlavorMap.decodeJavaMIMEType(nat);
1063 return (retval_str != null)
1064 ? new DataFlavor(retval_str)
1065 : null;
1066 }
1067
1068 private static final class SoftCache<K, V> {
1069 Map<K, SoftReference<LinkedHashSet<V>>> cache;
1070
1071 public void put(K key, LinkedHashSet<V> value) {
1072 if (cache == null) {
1073 cache = new HashMap<>(1);
1074 }
1075 cache.put(key, new SoftReference<>(value));
1076 }
1077
1078 public void remove(K key) {
1079 if (cache == null) return;
1080 cache.remove(null);
1081 cache.remove(key);
1082 }
1083
1084 public LinkedHashSet<V> check(K key) {
1085 if (cache == null) return null;
1086 SoftReference<LinkedHashSet<V>> ref = cache.get(key);
1087 if (ref != null) {
1088 return ref.get();
1089 }
1090 return null;
1091 }
1092 }
1093 }