275 /**
276 * Returns font metrics for a font.
277 *
278 * @param f the font
279 * @return the metrics
280 */
281 public FontMetrics getFontMetrics(Font f) {
282 // The Toolkit implementations cache, so we just forward
283 // to the default toolkit.
284 return Toolkit.getDefaultToolkit().getFontMetrics(f);
285 }
286
287 // --- AttributeContext methods --------------------
288
289 /**
290 * Adds an attribute to the given set, and returns
291 * the new representative set.
292 * <p>
293 * This method is thread safe, although most Swing methods
294 * are not. Please see
295 * <A HREF="http://download.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
296 * in Swing</A> for more information.
297 *
298 * @param old the old attribute set
299 * @param name the non-null attribute name
300 * @param value the attribute value
301 * @return the updated attribute set
302 * @see MutableAttributeSet#addAttribute
303 */
304 public synchronized AttributeSet addAttribute(AttributeSet old, Object name, Object value) {
305 if ((old.getAttributeCount() + 1) <= getCompressionThreshold()) {
306 // build a search key and find/create an immutable and unique
307 // set.
308 search.removeAttributes(search);
309 search.addAttributes(old);
310 search.addAttribute(name, value);
311 reclaim(old);
312 return getImmutableUniqueSet();
313 }
314 MutableAttributeSet ma = getMutableAttributeSet(old);
315 ma.addAttribute(name, value);
316 return ma;
317 }
318
319 /**
320 * Adds a set of attributes to the element.
321 * <p>
322 * This method is thread safe, although most Swing methods
323 * are not. Please see
324 * <A HREF="http://download.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
325 * in Swing</A> for more information.
326 *
327 * @param old the old attribute set
328 * @param attr the attributes to add
329 * @return the updated attribute set
330 * @see MutableAttributeSet#addAttribute
331 */
332 public synchronized AttributeSet addAttributes(AttributeSet old, AttributeSet attr) {
333 if ((old.getAttributeCount() + attr.getAttributeCount()) <= getCompressionThreshold()) {
334 // build a search key and find/create an immutable and unique
335 // set.
336 search.removeAttributes(search);
337 search.addAttributes(old);
338 search.addAttributes(attr);
339 reclaim(old);
340 return getImmutableUniqueSet();
341 }
342 MutableAttributeSet ma = getMutableAttributeSet(old);
343 ma.addAttributes(attr);
344 return ma;
345 }
346
347 /**
348 * Removes an attribute from the set.
349 * <p>
350 * This method is thread safe, although most Swing methods
351 * are not. Please see
352 * <A HREF="http://download.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
353 * in Swing</A> for more information.
354 *
355 * @param old the old set of attributes
356 * @param name the non-null attribute name
357 * @return the updated attribute set
358 * @see MutableAttributeSet#removeAttribute
359 */
360 public synchronized AttributeSet removeAttribute(AttributeSet old, Object name) {
361 if ((old.getAttributeCount() - 1) <= getCompressionThreshold()) {
362 // build a search key and find/create an immutable and unique
363 // set.
364 search.removeAttributes(search);
365 search.addAttributes(old);
366 search.removeAttribute(name);
367 reclaim(old);
368 return getImmutableUniqueSet();
369 }
370 MutableAttributeSet ma = getMutableAttributeSet(old);
371 ma.removeAttribute(name);
372 return ma;
373 }
374
375 /**
376 * Removes a set of attributes for the element.
377 * <p>
378 * This method is thread safe, although most Swing methods
379 * are not. Please see
380 * <A HREF="http://download.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
381 * in Swing</A> for more information.
382 *
383 * @param old the old attribute set
384 * @param names the attribute names
385 * @return the updated attribute set
386 * @see MutableAttributeSet#removeAttributes
387 */
388 public synchronized AttributeSet removeAttributes(AttributeSet old, Enumeration<?> names) {
389 if (old.getAttributeCount() <= getCompressionThreshold()) {
390 // build a search key and find/create an immutable and unique
391 // set.
392 search.removeAttributes(search);
393 search.addAttributes(old);
394 search.removeAttributes(names);
395 reclaim(old);
396 return getImmutableUniqueSet();
397 }
398 MutableAttributeSet ma = getMutableAttributeSet(old);
399 ma.removeAttributes(names);
400 return ma;
401 }
402
403 /**
404 * Removes a set of attributes for the element.
405 * <p>
406 * This method is thread safe, although most Swing methods
407 * are not. Please see
408 * <A HREF="http://download.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
409 * in Swing</A> for more information.
410 *
411 * @param old the old attribute set
412 * @param attrs the attributes
413 * @return the updated attribute set
414 * @see MutableAttributeSet#removeAttributes
415 */
416 public synchronized AttributeSet removeAttributes(AttributeSet old, AttributeSet attrs) {
417 if (old.getAttributeCount() <= getCompressionThreshold()) {
418 // build a search key and find/create an immutable and unique
419 // set.
420 search.removeAttributes(search);
421 search.addAttributes(old);
422 search.removeAttributes(attrs);
423 reclaim(old);
424 return getImmutableUniqueSet();
425 }
426 MutableAttributeSet ma = getMutableAttributeSet(old);
427 ma.removeAttributes(attrs);
428 return ma;
429 }
430
431 /**
432 * Fetches an empty AttributeSet.
433 *
434 * @return the set
435 */
436 public AttributeSet getEmptySet() {
437 return SimpleAttributeSet.EMPTY;
438 }
439
440 /**
441 * Returns a set no longer needed by the MutableAttributeSet implmentation.
442 * This is useful for operation under 1.1 where there are no weak
443 * references. This would typically be called by the finalize method
444 * of the MutableAttributeSet implementation.
445 * <p>
446 * This method is thread safe, although most Swing methods
447 * are not. Please see
448 * <A HREF="http://download.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
449 * in Swing</A> for more information.
450 *
451 * @param a the set to reclaim
452 */
453 public void reclaim(AttributeSet a) {
454 if (SwingUtilities.isEventDispatchThread()) {
455 attributesPool.size(); // force WeakHashMap to expunge stale entries
456 }
457 // if current thread is not event dispatching thread
458 // do not bother with expunging stale entries.
459 }
460
461 // --- local methods -----------------------------------------------
462
463 /**
464 * Returns the maximum number of key/value pairs to try and
465 * compress into unique/immutable sets. Any sets above this
466 * limit will use hashtables and be a MutableAttributeSet.
467 *
468 * @return the threshold
|
275 /**
276 * Returns font metrics for a font.
277 *
278 * @param f the font
279 * @return the metrics
280 */
281 public FontMetrics getFontMetrics(Font f) {
282 // The Toolkit implementations cache, so we just forward
283 // to the default toolkit.
284 return Toolkit.getDefaultToolkit().getFontMetrics(f);
285 }
286
287 // --- AttributeContext methods --------------------
288
289 /**
290 * Adds an attribute to the given set, and returns
291 * the new representative set.
292 * <p>
293 * This method is thread safe, although most Swing methods
294 * are not. Please see
295 * <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
296 * in Swing</A> for more information.
297 *
298 * @param old the old attribute set
299 * @param name the non-null attribute name
300 * @param value the attribute value
301 * @return the updated attribute set
302 * @see MutableAttributeSet#addAttribute
303 */
304 public synchronized AttributeSet addAttribute(AttributeSet old, Object name, Object value) {
305 if ((old.getAttributeCount() + 1) <= getCompressionThreshold()) {
306 // build a search key and find/create an immutable and unique
307 // set.
308 search.removeAttributes(search);
309 search.addAttributes(old);
310 search.addAttribute(name, value);
311 reclaim(old);
312 return getImmutableUniqueSet();
313 }
314 MutableAttributeSet ma = getMutableAttributeSet(old);
315 ma.addAttribute(name, value);
316 return ma;
317 }
318
319 /**
320 * Adds a set of attributes to the element.
321 * <p>
322 * This method is thread safe, although most Swing methods
323 * are not. Please see
324 * <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
325 * in Swing</A> for more information.
326 *
327 * @param old the old attribute set
328 * @param attr the attributes to add
329 * @return the updated attribute set
330 * @see MutableAttributeSet#addAttribute
331 */
332 public synchronized AttributeSet addAttributes(AttributeSet old, AttributeSet attr) {
333 if ((old.getAttributeCount() + attr.getAttributeCount()) <= getCompressionThreshold()) {
334 // build a search key and find/create an immutable and unique
335 // set.
336 search.removeAttributes(search);
337 search.addAttributes(old);
338 search.addAttributes(attr);
339 reclaim(old);
340 return getImmutableUniqueSet();
341 }
342 MutableAttributeSet ma = getMutableAttributeSet(old);
343 ma.addAttributes(attr);
344 return ma;
345 }
346
347 /**
348 * Removes an attribute from the set.
349 * <p>
350 * This method is thread safe, although most Swing methods
351 * are not. Please see
352 * <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
353 * in Swing</A> for more information.
354 *
355 * @param old the old set of attributes
356 * @param name the non-null attribute name
357 * @return the updated attribute set
358 * @see MutableAttributeSet#removeAttribute
359 */
360 public synchronized AttributeSet removeAttribute(AttributeSet old, Object name) {
361 if ((old.getAttributeCount() - 1) <= getCompressionThreshold()) {
362 // build a search key and find/create an immutable and unique
363 // set.
364 search.removeAttributes(search);
365 search.addAttributes(old);
366 search.removeAttribute(name);
367 reclaim(old);
368 return getImmutableUniqueSet();
369 }
370 MutableAttributeSet ma = getMutableAttributeSet(old);
371 ma.removeAttribute(name);
372 return ma;
373 }
374
375 /**
376 * Removes a set of attributes for the element.
377 * <p>
378 * This method is thread safe, although most Swing methods
379 * are not. Please see
380 * <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
381 * in Swing</A> for more information.
382 *
383 * @param old the old attribute set
384 * @param names the attribute names
385 * @return the updated attribute set
386 * @see MutableAttributeSet#removeAttributes
387 */
388 public synchronized AttributeSet removeAttributes(AttributeSet old, Enumeration<?> names) {
389 if (old.getAttributeCount() <= getCompressionThreshold()) {
390 // build a search key and find/create an immutable and unique
391 // set.
392 search.removeAttributes(search);
393 search.addAttributes(old);
394 search.removeAttributes(names);
395 reclaim(old);
396 return getImmutableUniqueSet();
397 }
398 MutableAttributeSet ma = getMutableAttributeSet(old);
399 ma.removeAttributes(names);
400 return ma;
401 }
402
403 /**
404 * Removes a set of attributes for the element.
405 * <p>
406 * This method is thread safe, although most Swing methods
407 * are not. Please see
408 * <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
409 * in Swing</A> for more information.
410 *
411 * @param old the old attribute set
412 * @param attrs the attributes
413 * @return the updated attribute set
414 * @see MutableAttributeSet#removeAttributes
415 */
416 public synchronized AttributeSet removeAttributes(AttributeSet old, AttributeSet attrs) {
417 if (old.getAttributeCount() <= getCompressionThreshold()) {
418 // build a search key and find/create an immutable and unique
419 // set.
420 search.removeAttributes(search);
421 search.addAttributes(old);
422 search.removeAttributes(attrs);
423 reclaim(old);
424 return getImmutableUniqueSet();
425 }
426 MutableAttributeSet ma = getMutableAttributeSet(old);
427 ma.removeAttributes(attrs);
428 return ma;
429 }
430
431 /**
432 * Fetches an empty AttributeSet.
433 *
434 * @return the set
435 */
436 public AttributeSet getEmptySet() {
437 return SimpleAttributeSet.EMPTY;
438 }
439
440 /**
441 * Returns a set no longer needed by the MutableAttributeSet implmentation.
442 * This is useful for operation under 1.1 where there are no weak
443 * references. This would typically be called by the finalize method
444 * of the MutableAttributeSet implementation.
445 * <p>
446 * This method is thread safe, although most Swing methods
447 * are not. Please see
448 * <A HREF="http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html">Concurrency
449 * in Swing</A> for more information.
450 *
451 * @param a the set to reclaim
452 */
453 public void reclaim(AttributeSet a) {
454 if (SwingUtilities.isEventDispatchThread()) {
455 attributesPool.size(); // force WeakHashMap to expunge stale entries
456 }
457 // if current thread is not event dispatching thread
458 // do not bother with expunging stale entries.
459 }
460
461 // --- local methods -----------------------------------------------
462
463 /**
464 * Returns the maximum number of key/value pairs to try and
465 * compress into unique/immutable sets. Any sets above this
466 * limit will use hashtables and be a MutableAttributeSet.
467 *
468 * @return the threshold
|