1 /*
2 * Copyright (c) 1996, 2018, 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.util.zip;
27
28 import java.lang.ref.Cleaner.Cleanable;
29 import java.lang.ref.Reference;
30 import java.nio.ByteBuffer;
31 import java.nio.ReadOnlyBufferException;
32 import java.util.Objects;
33
34 import jdk.internal.ref.CleanerFactory;
35 import sun.nio.ch.DirectBuffer;
36
37 /**
38 * This class provides support for general purpose decompression using the
39 * popular ZLIB compression library. The ZLIB compression library was
40 * initially developed as part of the PNG graphics standard and is not
41 * protected by patents. It is fully described in the specifications at
42 * the <a href="package-summary.html#package.description">java.util.zip
43 * package description</a>.
44 * <p>
45 * This class inflates sequences of ZLIB compressed bytes. The input byte
46 * sequence is provided in either byte array or byte buffer, via one of the
47 * {@code setInput()} methods. The output byte sequence is written to the
48 * output byte array or byte buffer passed to the {@code deflate()} methods.
49 * <p>
50 * The following code fragment demonstrates a trivial compression
51 * and decompression of a string using {@code Deflater} and
52 * {@code Inflater}.
53 *
54 * <blockquote><pre>
55 * try {
56 * // Encode a String into bytes
57 * String inputString = "blahblahblah\u20AC\u20AC";
58 * byte[] input = inputString.getBytes("UTF-8");
59 *
60 * // Compress the bytes
61 * byte[] output = new byte[100];
62 * Deflater compresser = new Deflater();
63 * compresser.setInput(input);
64 * compresser.finish();
65 * int compressedDataLength = compresser.deflate(output);
66 *
67 * // Decompress the bytes
68 * Inflater decompresser = new Inflater();
69 * decompresser.setInput(output, 0, compressedDataLength);
70 * byte[] result = new byte[100];
71 * int resultLength = decompresser.inflate(result);
72 * decompresser.end();
73 *
74 * // Decode the bytes into a String
75 * String outputString = new String(result, 0, resultLength, "UTF-8");
76 * } catch(java.io.UnsupportedEncodingException ex) {
77 * // handle
78 * } catch (java.util.zip.DataFormatException ex) {
79 * // handle
80 * }
81 * </pre></blockquote>
82 *
83 * @apiNote
84 * To release resources used by this {@code Inflater}, the {@link #end()} method
85 * should be called explicitly. Subclasses are responsible for the cleanup of resources
86 * acquired by the subclass. Subclasses that override {@link #finalize()} in order
87 * to perform cleanup should be modified to use alternative cleanup mechanisms such
88 * as {@link java.lang.ref.Cleaner} and remove the overriding {@code finalize} method.
89 *
90 * @implSpec
91 * If this {@code Inflater} has been subclassed and the {@code end} method has been
92 * overridden, the {@code end} method will be called by the finalization when the
93 * inflater is unreachable. But the subclasses should not depend on this specific
94 * implementation; the finalization is not reliable and the {@code finalize} method
95 * is deprecated to be removed.
96 *
97 * @see Deflater
98 * @author David Connelly
99 * @since 1.1
100 *
101 */
102
103 public class Inflater {
104
105 private final InflaterZStreamRef zsRef;
106 private ByteBuffer input = ZipUtils.defaultBuf;
107 private byte[] inputArray;
108 private int inputPos, inputLim;
109 private boolean finished;
110 private boolean needDict;
111 private long bytesRead;
112 private long bytesWritten;
113
114 /*
115 * These fields are used as an "out" parameter from JNI when a
116 * DataFormatException is thrown during the inflate operation.
117 */
118 private int inputConsumed;
119 private int outputConsumed;
120
121 static {
122 ZipUtils.loadLibrary();
123 initIDs();
124 }
125
126 /**
127 * Creates a new decompressor. If the parameter 'nowrap' is true then
128 * the ZLIB header and checksum fields will not be used. This provides
129 * compatibility with the compression format used by both GZIP and PKZIP.
130 * <p>
131 * Note: When using the 'nowrap' option it is also necessary to provide
132 * an extra "dummy" byte as input. This is required by the ZLIB native
133 * library in order to support certain optimizations.
134 *
135 * @param nowrap if true then support GZIP compatible compression
136 */
137 public Inflater(boolean nowrap) {
138 this.zsRef = InflaterZStreamRef.get(this, init(nowrap));
139 }
140
141 /**
142 * Creates a new decompressor.
143 */
144 public Inflater() {
145 this(false);
146 }
147
148 /**
149 * Sets input data for decompression.
150 * <p>
151 * One of the {@code setInput()} methods should be called whenever
152 * {@code needsInput()} returns true indicating that more input data
153 * is required.
154 *
155 * @param input the input data bytes
156 * @param off the start offset of the input data
157 * @param len the length of the input data
158 * @see Inflater#needsInput
159 */
160 public void setInput(byte[] input, int off, int len) {
161 if (off < 0 || len < 0 || off > input.length - len) {
162 throw new ArrayIndexOutOfBoundsException();
163 }
164 synchronized (zsRef) {
165 this.input = null;
166 this.inputArray = input;
167 this.inputPos = off;
168 this.inputLim = off + len;
169 }
170 }
171
172 /**
173 * Sets input data for decompression.
174 * <p>
175 * One of the {@code setInput()} methods should be called whenever
176 * {@code needsInput()} returns true indicating that more input data
177 * is required.
178 *
179 * @param input the input data bytes
180 * @see Inflater#needsInput
181 */
182 public void setInput(byte[] input) {
183 setInput(input, 0, input.length);
184 }
185
186 /**
187 * Sets input data for decompression.
188 * <p>
189 * One of the {@code setInput()} methods should be called whenever
190 * {@code needsInput()} returns true indicating that more input data
191 * is required.
192 * <p>
193 * The given buffer's position will be advanced as inflate
194 * operations are performed, up to the buffer's limit.
195 * The input buffer may be modified (refilled) between inflate
196 * operations; doing so is equivalent to creating a new buffer
197 * and setting it with this method.
198 * <p>
199 * Modifying the input buffer's contents, position, or limit
200 * concurrently with an inflate operation will result in
201 * undefined behavior, which may include incorrect operation
202 * results or operation failure.
203 *
204 * @param input the input data bytes
205 * @see Inflater#needsInput
206 * @since 11
207 */
208 public void setInput(ByteBuffer input) {
209 Objects.requireNonNull(input);
210 synchronized (zsRef) {
211 this.input = input;
212 this.inputArray = null;
213 }
214 }
215
216 /**
217 * Sets the preset dictionary to the given array of bytes. Should be
218 * called when inflate() returns 0 and needsDictionary() returns true
219 * indicating that a preset dictionary is required. The method getAdler()
220 * can be used to get the Adler-32 value of the dictionary needed.
221 * @param dictionary the dictionary data bytes
222 * @param off the start offset of the data
223 * @param len the length of the data
224 * @see Inflater#needsDictionary
225 * @see Inflater#getAdler
226 */
227 public void setDictionary(byte[] dictionary, int off, int len) {
228 if (off < 0 || len < 0 || off > dictionary.length - len) {
229 throw new ArrayIndexOutOfBoundsException();
230 }
231 synchronized (zsRef) {
232 ensureOpen();
233 setDictionary(zsRef.address(), dictionary, off, len);
234 needDict = false;
235 }
236 }
237
238 /**
239 * Sets the preset dictionary to the given array of bytes. Should be
240 * called when inflate() returns 0 and needsDictionary() returns true
241 * indicating that a preset dictionary is required. The method getAdler()
242 * can be used to get the Adler-32 value of the dictionary needed.
243 * @param dictionary the dictionary data bytes
244 * @see Inflater#needsDictionary
245 * @see Inflater#getAdler
246 */
247 public void setDictionary(byte[] dictionary) {
248 setDictionary(dictionary, 0, dictionary.length);
249 }
250
251 /**
252 * Sets the preset dictionary to the bytes in the given buffer. Should be
253 * called when inflate() returns 0 and needsDictionary() returns true
254 * indicating that a preset dictionary is required. The method getAdler()
255 * can be used to get the Adler-32 value of the dictionary needed.
256 * <p>
257 * The bytes in given byte buffer will be fully consumed by this method. On
258 * return, its position will equal its limit.
259 *
260 * @param dictionary the dictionary data bytes
261 * @see Inflater#needsDictionary
262 * @see Inflater#getAdler
263 * @since 11
264 */
265 public void setDictionary(ByteBuffer dictionary) {
266 synchronized (zsRef) {
267 int position = dictionary.position();
268 int remaining = Math.max(dictionary.limit() - position, 0);
269 ensureOpen();
270 if (dictionary.isDirect()) {
271 long address = ((DirectBuffer) dictionary).address();
272 try {
273 setDictionaryBuffer(zsRef.address(), address + position, remaining);
274 } finally {
275 Reference.reachabilityFence(dictionary);
276 }
277 } else {
278 byte[] array = ZipUtils.getBufferArray(dictionary);
279 int offset = ZipUtils.getBufferOffset(dictionary);
280 setDictionary(zsRef.address(), array, offset + position, remaining);
281 }
282 dictionary.position(position + remaining);
283 needDict = false;
284 }
285 }
286
287 /**
288 * Returns the total number of bytes remaining in the input buffer.
289 * This can be used to find out what bytes still remain in the input
290 * buffer after decompression has finished.
291 * @return the total number of bytes remaining in the input buffer
292 */
293 public int getRemaining() {
294 synchronized (zsRef) {
295 ByteBuffer input = this.input;
296 return input == null ? inputLim - inputPos : input.remaining();
297 }
298 }
299
300 /**
301 * Returns true if no data remains in the input buffer. This can
302 * be used to determine if one of the {@code setInput()} methods should be
303 * called in order to provide more input.
304 *
305 * @return true if no data remains in the input buffer
306 */
307 public boolean needsInput() {
308 synchronized (zsRef) {
309 ByteBuffer input = this.input;
310 return input == null ? inputLim == inputPos : ! input.hasRemaining();
311 }
312 }
313
314 /**
315 * Returns true if a preset dictionary is needed for decompression.
316 * @return true if a preset dictionary is needed for decompression
317 * @see Inflater#setDictionary
318 */
319 public boolean needsDictionary() {
320 synchronized (zsRef) {
321 return needDict;
322 }
323 }
324
325 /**
326 * Returns true if the end of the compressed data stream has been
327 * reached.
328 * @return true if the end of the compressed data stream has been
329 * reached
330 */
331 public boolean finished() {
332 synchronized (zsRef) {
333 return finished;
334 }
335 }
336
337 /**
338 * Uncompresses bytes into specified buffer. Returns actual number
339 * of bytes uncompressed. A return value of 0 indicates that
340 * needsInput() or needsDictionary() should be called in order to
341 * determine if more input data or a preset dictionary is required.
342 * In the latter case, getAdler() can be used to get the Adler-32
343 * value of the dictionary required.
344 * <p>
345 * If the {@link #setInput(ByteBuffer)} method was called to provide a buffer
346 * for input, the input buffer's position will be advanced by the number of bytes
347 * consumed by this operation, even in the event that a {@link DataFormatException}
348 * is thrown.
349 * <p>
350 * The {@linkplain #getRemaining() remaining byte count} will be reduced by
351 * the number of consumed input bytes. If the {@link #setInput(ByteBuffer)}
352 * method was called to provide a buffer for input, the input buffer's position
353 * will be advanced the number of consumed bytes.
354 * <p>
355 * These byte totals, as well as
356 * the {@linkplain #getBytesRead() total bytes read}
357 * and the {@linkplain #getBytesWritten() total bytes written}
358 * values, will be updated even in the event that a {@link DataFormatException}
359 * is thrown to reflect the amount of data consumed and produced before the
360 * exception occurred.
361 *
362 * @param output the buffer for the uncompressed data
363 * @param off the start offset of the data
364 * @param len the maximum number of uncompressed bytes
365 * @return the actual number of uncompressed bytes
366 * @throws DataFormatException if the compressed data format is invalid
367 * @see Inflater#needsInput
368 * @see Inflater#needsDictionary
369 */
370 public int inflate(byte[] output, int off, int len)
371 throws DataFormatException
372 {
373 if (off < 0 || len < 0 || off > output.length - len) {
374 throw new ArrayIndexOutOfBoundsException();
375 }
376 synchronized (zsRef) {
377 ensureOpen();
378 ByteBuffer input = this.input;
379 long result;
380 int inputPos;
381 try {
382 if (input == null) {
383 inputPos = this.inputPos;
384 try {
385 result = inflateBytesBytes(zsRef.address(),
386 inputArray, inputPos, inputLim - inputPos,
387 output, off, len);
388 } catch (DataFormatException e) {
389 this.inputPos = inputPos + inputConsumed;
390 throw e;
391 }
392 } else {
393 inputPos = input.position();
394 try {
395 int inputRem = Math.max(input.limit() - inputPos, 0);
396 if (input.isDirect()) {
397 try {
398 long inputAddress = ((DirectBuffer) input).address();
399 result = inflateBufferBytes(zsRef.address(),
400 inputAddress + inputPos, inputRem,
401 output, off, len);
402 } finally {
403 Reference.reachabilityFence(input);
404 }
405 } else {
406 byte[] inputArray = ZipUtils.getBufferArray(input);
407 int inputOffset = ZipUtils.getBufferOffset(input);
408 result = inflateBytesBytes(zsRef.address(),
409 inputArray, inputOffset + inputPos, inputRem,
410 output, off, len);
411 }
412 } catch (DataFormatException e) {
413 input.position(inputPos + inputConsumed);
414 throw e;
415 }
416 }
417 } catch (DataFormatException e) {
418 bytesRead += inputConsumed;
419 inputConsumed = 0;
420 int written = outputConsumed;
421 bytesWritten += written;
422 outputConsumed = 0;
423 throw e;
424 }
425 int read = (int) (result & 0x7fff_ffffL);
426 int written = (int) (result >>> 31 & 0x7fff_ffffL);
427 if ((result >>> 62 & 1) != 0) {
428 finished = true;
429 }
430 if ((result >>> 63 & 1) != 0) {
431 needDict = true;
432 }
433 if (input != null) {
434 input.position(inputPos + read);
435 } else {
436 this.inputPos = inputPos + read;
437 }
438 bytesWritten += written;
439 bytesRead += read;
440 return written;
441 }
442 }
443
444 /**
445 * Uncompresses bytes into specified buffer. Returns actual number
446 * of bytes uncompressed. A return value of 0 indicates that
447 * needsInput() or needsDictionary() should be called in order to
448 * determine if more input data or a preset dictionary is required.
449 * In the latter case, getAdler() can be used to get the Adler-32
450 * value of the dictionary required.
451 * <p>
452 * The {@linkplain #getRemaining() remaining byte count} will be reduced by
453 * the number of consumed input bytes. If the {@link #setInput(ByteBuffer)}
454 * method was called to provide a buffer for input, the input buffer's position
455 * will be advanced the number of consumed bytes.
456 * <p>
457 * These byte totals, as well as
458 * the {@linkplain #getBytesRead() total bytes read}
459 * and the {@linkplain #getBytesWritten() total bytes written}
460 * values, will be updated even in the event that a {@link DataFormatException}
461 * is thrown to reflect the amount of data consumed and produced before the
462 * exception occurred.
463 *
464 * @param output the buffer for the uncompressed data
465 * @return the actual number of uncompressed bytes
466 * @throws DataFormatException if the compressed data format is invalid
467 * @see Inflater#needsInput
468 * @see Inflater#needsDictionary
469 */
470 public int inflate(byte[] output) throws DataFormatException {
471 return inflate(output, 0, output.length);
472 }
473
474 /**
475 * Uncompresses bytes into specified buffer. Returns actual number
476 * of bytes uncompressed. A return value of 0 indicates that
477 * needsInput() or needsDictionary() should be called in order to
478 * determine if more input data or a preset dictionary is required.
479 * In the latter case, getAdler() can be used to get the Adler-32
480 * value of the dictionary required.
481 * <p>
482 * On success, the position of the given {@code output} byte buffer will be
483 * advanced by as many bytes as were produced by the operation, which is equal
484 * to the number returned by this method. Note that the position of the
485 * {@code output} buffer will be advanced even in the event that a
486 * {@link DataFormatException} is thrown.
487 * <p>
488 * The {@linkplain #getRemaining() remaining byte count} will be reduced by
489 * the number of consumed input bytes. If the {@link #setInput(ByteBuffer)}
490 * method was called to provide a buffer for input, the input buffer's position
491 * will be advanced the number of consumed bytes.
492 * <p>
493 * These byte totals, as well as
494 * the {@linkplain #getBytesRead() total bytes read}
495 * and the {@linkplain #getBytesWritten() total bytes written}
496 * values, will be updated even in the event that a {@link DataFormatException}
497 * is thrown to reflect the amount of data consumed and produced before the
498 * exception occurred.
499 *
500 * @param output the buffer for the uncompressed data
501 * @return the actual number of uncompressed bytes
502 * @throws DataFormatException if the compressed data format is invalid
503 * @throws ReadOnlyBufferException if the given output buffer is read-only
504 * @see Inflater#needsInput
505 * @see Inflater#needsDictionary
506 * @since 11
507 */
508 public int inflate(ByteBuffer output) throws DataFormatException {
509 if (output.isReadOnly()) {
510 throw new ReadOnlyBufferException();
511 }
512 synchronized (zsRef) {
513 ensureOpen();
514 ByteBuffer input = this.input;
515 long result;
516 int inputPos;
517 int outputPos = output.position();
518 int outputRem = Math.max(output.limit() - outputPos, 0);
519 try {
520 if (input == null) {
521 inputPos = this.inputPos;
522 try {
523 if (output.isDirect()) {
524 long outputAddress = ((DirectBuffer) output).address();
525 try {
526 result = inflateBytesBuffer(zsRef.address(),
527 inputArray, inputPos, inputLim - inputPos,
528 outputAddress + outputPos, outputRem);
529 } finally {
530 Reference.reachabilityFence(output);
531 }
532 } else {
533 byte[] outputArray = ZipUtils.getBufferArray(output);
534 int outputOffset = ZipUtils.getBufferOffset(output);
535 result = inflateBytesBytes(zsRef.address(),
536 inputArray, inputPos, inputLim - inputPos,
537 outputArray, outputOffset + outputPos, outputRem);
538 }
539 } catch (DataFormatException e) {
540 this.inputPos = inputPos + inputConsumed;
541 throw e;
542 }
543 } else {
544 inputPos = input.position();
545 int inputRem = Math.max(input.limit() - inputPos, 0);
546 try {
547 if (input.isDirect()) {
548 long inputAddress = ((DirectBuffer) input).address();
549 try {
550 if (output.isDirect()) {
551 long outputAddress = ((DirectBuffer) output).address();
552 try {
553 result = inflateBufferBuffer(zsRef.address(),
554 inputAddress + inputPos, inputRem,
555 outputAddress + outputPos, outputRem);
556 } finally {
557 Reference.reachabilityFence(output);
558 }
559 } else {
560 byte[] outputArray = ZipUtils.getBufferArray(output);
561 int outputOffset = ZipUtils.getBufferOffset(output);
562 result = inflateBufferBytes(zsRef.address(),
563 inputAddress + inputPos, inputRem,
564 outputArray, outputOffset + outputPos, outputRem);
565 }
566 } finally {
567 Reference.reachabilityFence(input);
568 }
569 } else {
570 byte[] inputArray = ZipUtils.getBufferArray(input);
571 int inputOffset = ZipUtils.getBufferOffset(input);
572 if (output.isDirect()) {
573 long outputAddress = ((DirectBuffer) output).address();
574 try {
575 result = inflateBytesBuffer(zsRef.address(),
576 inputArray, inputOffset + inputPos, inputRem,
577 outputAddress + outputPos, outputRem);
578 } finally {
579 Reference.reachabilityFence(output);
580 }
581 } else {
582 byte[] outputArray = ZipUtils.getBufferArray(output);
583 int outputOffset = ZipUtils.getBufferOffset(output);
584 result = inflateBytesBytes(zsRef.address(),
585 inputArray, inputOffset + inputPos, inputRem,
586 outputArray, outputOffset + outputPos, outputRem);
587 }
588 }
589 } catch (DataFormatException e) {
590 input.position(inputPos + inputConsumed);
591 throw e;
592 }
593 }
594 } catch (DataFormatException e) {
595 bytesRead += inputConsumed;
596 inputConsumed = 0;
597 int written = outputConsumed;
598 output.position(outputPos + written);
599 bytesWritten += written;
600 outputConsumed = 0;
601 throw e;
602 }
603 int read = (int) (result & 0x7fff_ffffL);
604 int written = (int) (result >>> 31 & 0x7fff_ffffL);
605 if ((result >>> 62 & 1) != 0) {
606 finished = true;
607 }
608 if ((result >>> 63 & 1) != 0) {
609 needDict = true;
610 }
611 if (input != null) {
612 input.position(inputPos + read);
613 } else {
614 this.inputPos = inputPos + read;
615 }
616 // Note: this method call also serves to keep the byteBuffer ref alive
617 output.position(outputPos + written);
618 bytesWritten += written;
619 bytesRead += read;
620 return written;
621 }
622 }
623
624 /**
625 * Returns the ADLER-32 value of the uncompressed data.
626 * @return the ADLER-32 value of the uncompressed data
627 */
628 public int getAdler() {
629 synchronized (zsRef) {
630 ensureOpen();
631 return getAdler(zsRef.address());
632 }
633 }
634
635 /**
636 * Returns the total number of compressed bytes input so far.
637 *
638 * <p>Since the number of bytes may be greater than
639 * Integer.MAX_VALUE, the {@link #getBytesRead()} method is now
640 * the preferred means of obtaining this information.</p>
641 *
642 * @return the total number of compressed bytes input so far
643 */
644 public int getTotalIn() {
645 return (int) getBytesRead();
646 }
647
648 /**
649 * Returns the total number of compressed bytes input so far.
650 *
651 * @return the total (non-negative) number of compressed bytes input so far
652 * @since 1.5
653 */
654 public long getBytesRead() {
655 synchronized (zsRef) {
656 ensureOpen();
657 return bytesRead;
658 }
659 }
660
661 /**
662 * Returns the total number of uncompressed bytes output so far.
663 *
664 * <p>Since the number of bytes may be greater than
665 * Integer.MAX_VALUE, the {@link #getBytesWritten()} method is now
666 * the preferred means of obtaining this information.</p>
667 *
668 * @return the total number of uncompressed bytes output so far
669 */
670 public int getTotalOut() {
671 return (int) getBytesWritten();
672 }
673
674 /**
675 * Returns the total number of uncompressed bytes output so far.
676 *
677 * @return the total (non-negative) number of uncompressed bytes output so far
678 * @since 1.5
679 */
680 public long getBytesWritten() {
681 synchronized (zsRef) {
682 ensureOpen();
683 return bytesWritten;
684 }
685 }
686
687 /**
688 * Resets inflater so that a new set of input data can be processed.
689 */
690 public void reset() {
691 synchronized (zsRef) {
692 ensureOpen();
693 reset(zsRef.address());
694 input = ZipUtils.defaultBuf;
695 inputArray = null;
696 finished = false;
697 needDict = false;
698 bytesRead = bytesWritten = 0;
699 }
700 }
701
702 /**
703 * Closes the decompressor and discards any unprocessed input.
704 *
705 * This method should be called when the decompressor is no longer
706 * being used. Once this method is called, the behavior of the
707 * Inflater object is undefined.
708 */
709 public void end() {
710 synchronized (zsRef) {
711 zsRef.clean();
712 input = ZipUtils.defaultBuf;
713 inputArray = null;
714 }
715 }
716
717 /**
718 * Closes the decompressor when garbage is collected.
719 *
720 * @implSpec
721 * If this {@code Inflater} has been subclassed and the {@code end} method
722 * has been overridden, the {@code end} method will be called when the
723 * inflater is unreachable.
724 *
725 * @deprecated The {@code finalize} method has been deprecated and will be
726 * removed. It is implemented as a no-op. Subclasses that override
727 * {@code finalize} in order to perform cleanup should be modified to use
728 * alternative cleanup mechanisms and remove the overriding {@code finalize}
729 * method. The recommended cleanup for compressor is to explicitly call
730 * {@code end} method when it is no longer in use. If the {@code end} is
731 * not invoked explicitly the resource of the compressor will be released
732 * when the instance becomes unreachable,
733 */
734 @Deprecated(since="9", forRemoval=true)
735 protected void finalize() {}
736
737 private void ensureOpen () {
738 assert Thread.holdsLock(zsRef);
739 if (zsRef.address() == 0)
740 throw new NullPointerException("Inflater has been closed");
741 }
742
743 private static native void initIDs();
744 private static native long init(boolean nowrap);
745 private static native void setDictionary(long addr, byte[] b, int off,
746 int len);
747 private static native void setDictionaryBuffer(long addr, long bufAddress, int len);
748 private native long inflateBytesBytes(long addr,
749 byte[] inputArray, int inputOff, int inputLen,
750 byte[] outputArray, int outputOff, int outputLen) throws DataFormatException;
751 private native long inflateBytesBuffer(long addr,
752 byte[] inputArray, int inputOff, int inputLen,
753 long outputAddress, int outputLen) throws DataFormatException;
754 private native long inflateBufferBytes(long addr,
755 long inputAddress, int inputLen,
756 byte[] outputArray, int outputOff, int outputLen) throws DataFormatException;
757 private native long inflateBufferBuffer(long addr,
758 long inputAddress, int inputLen,
759 long outputAddress, int outputLen) throws DataFormatException;
760 private static native int getAdler(long addr);
761 private static native void reset(long addr);
762 private static native void end(long addr);
763
764 /**
765 * A reference to the native zlib's z_stream structure. It also
766 * serves as the "cleaner" to clean up the native resource when
767 * the Inflater is ended, closed or cleaned.
768 */
769 static class InflaterZStreamRef implements Runnable {
770
771 private long address;
772 private final Cleanable cleanable;
773
774 private InflaterZStreamRef(Inflater owner, long addr) {
775 this.cleanable = (owner != null) ? CleanerFactory.cleaner().register(owner, this) : null;
776 this.address = addr;
777 }
778
779 long address() {
780 return address;
781 }
782
783 void clean() {
784 cleanable.clean();
785 }
786
787 public synchronized void run() {
788 long addr = address;
789 address = 0;
790 if (addr != 0) {
791 end(addr);
792 }
793 }
794
795 /*
796 * If {@code Inflater} has been subclassed and the {@code end} method is
797 * overridden, uses {@code finalizer} mechanism for resource cleanup. So
798 * {@code end} method can be called when the {@code Inflater} is unreachable.
799 * This mechanism will be removed when the {@code finalize} method is
800 * removed from {@code Inflater}.
801 */
802 static InflaterZStreamRef get(Inflater owner, long addr) {
803 Class<?> clz = owner.getClass();
804 while (clz != Inflater.class) {
805 try {
806 clz.getDeclaredMethod("end");
807 return new FinalizableZStreamRef(owner, addr);
808 } catch (NoSuchMethodException nsme) {}
809 clz = clz.getSuperclass();
810 }
811 return new InflaterZStreamRef(owner, addr);
812 }
813
814 private static class FinalizableZStreamRef extends InflaterZStreamRef {
815 final Inflater owner;
816
817 FinalizableZStreamRef(Inflater owner, long addr) {
818 super(null, addr);
819 this.owner = owner;
820 }
821
822 @Override
823 void clean() {
824 run();
825 }
826
827 @Override
828 @SuppressWarnings("deprecation")
829 protected void finalize() {
830 owner.end();
831 }
832 }
833 }
834 }