Hide ParsableByteArray#data behind a getter

This allows us to enforce the limit because the array can only be
reassigned through reset(byte[]) or reset(byte[], int) (which update
the limit)

PiperOrigin-RevId: 323339960

extensions/flac/src/main/java/com/google/android/exoplayer2/ext/flac/FlacExtractor.java

@@ -210,7 +210,7 @@ private void decodeStreamMetadata(ExtractorInput input) throws IOException {
  if (this.streamMetadata == null) {
  this.streamMetadata = streamMetadata;
  outputBuffer.reset(streamMetadata.getMaxDecodedFrameSize());
- outputFrameHolder = new OutputFrameHolder(ByteBuffer.wrap(outputBuffer.data));
+ outputFrameHolder = new OutputFrameHolder(ByteBuffer.wrap(outputBuffer.getData()));
  binarySearchSeeker =
  outputSeekMap(
  flacDecoderJni,

library/common/src/main/java/com/google/android/exoplayer2/audio/Ac4Util.java

@@ -223,13 +223,14 @@ public static int parseAc4SyncframeAudioSampleCount(ByteBuffer buffer) {
  public static void getAc4SampleHeader(int size, ParsableByteArray buffer) {
  // See ETSI TS 103 190-1 V1.3.1, Annex G.
  buffer.reset(SAMPLE_HEADER_SIZE);
- buffer.data[0] = (byte) 0xAC;
- buffer.data[1] = 0x40;
- buffer.data[2] = (byte) 0xFF;
- buffer.data[3] = (byte) 0xFF;
- buffer.data[4] = (byte) ((size >> 16) & 0xFF);
- buffer.data[5] = (byte) ((size >> 8) & 0xFF);
- buffer.data[6] = (byte) (size & 0xFF);
+ byte[] data = buffer.getData();
+ data[0] = (byte) 0xAC;
+ data[1] = 0x40;
+ data[2] = (byte) 0xFF;
+ data[3] = (byte) 0xFF;
+ data[4] = (byte) ((size >> 16) & 0xFF);
+ data[5] = (byte) ((size >> 8) & 0xFF);
+ data[6] = (byte) (size & 0xFF);
  }
 
  private static int readVariableBits(ParsableBitArray data, int bitsPerRead) {

library/common/src/main/java/com/google/android/exoplayer2/metadata/emsg/EventMessageDecoder.java

@@ -38,7 +38,7 @@ public EventMessage decode(ParsableByteArray emsgData) {
  long durationMs = emsgData.readUnsignedInt();
  long id = emsgData.readUnsignedInt();
  byte[] messageData =
- Arrays.copyOfRange(emsgData.data, emsgData.getPosition(), emsgData.limit());
+ Arrays.copyOfRange(emsgData.getData(), emsgData.getPosition(), emsgData.limit());
  return new EventMessage(schemeIdUri, value, durationMs, id, messageData);
  }
 }

library/common/src/main/java/com/google/android/exoplayer2/metadata/id3/Id3Decoder.java

@@ -601,9 +601,10 @@ private static ChapterFrame decodeChapterFrame(
  @Nullable FramePredicate framePredicate)
  throws UnsupportedEncodingException {
  int framePosition = id3Data.getPosition();
- int chapterIdEndIndex = indexOfZeroByte(id3Data.data, framePosition);
- String chapterId = new String(id3Data.data, framePosition, chapterIdEndIndex - framePosition,
- "ISO-8859-1");
+ int chapterIdEndIndex = indexOfZeroByte(id3Data.getData(), framePosition);
+ String chapterId =
+ new String(
+ id3Data.getData(), framePosition, chapterIdEndIndex - framePosition, "ISO-8859-1");
  id3Data.setPosition(chapterIdEndIndex + 1);
 
  int startTime = id3Data.readInt();
@@ -640,9 +641,10 @@ private static ChapterTocFrame decodeChapterTOCFrame(
  @Nullable FramePredicate framePredicate)
  throws UnsupportedEncodingException {
  int framePosition = id3Data.getPosition();
- int elementIdEndIndex = indexOfZeroByte(id3Data.data, framePosition);
- String elementId = new String(id3Data.data, framePosition, elementIdEndIndex - framePosition,
- "ISO-8859-1");
+ int elementIdEndIndex = indexOfZeroByte(id3Data.getData(), framePosition);
+ String elementId =
+ new String(
+ id3Data.getData(), framePosition, elementIdEndIndex - framePosition, "ISO-8859-1");
  id3Data.setPosition(elementIdEndIndex + 1);
 
  int ctocFlags = id3Data.readUnsignedByte();
@@ -653,8 +655,8 @@ private static ChapterTocFrame decodeChapterTOCFrame(
  String[] children = new String[childCount];
  for (int i = 0; i < childCount; i++) {
  int startIndex = id3Data.getPosition();
- int endIndex = indexOfZeroByte(id3Data.data, startIndex);
- children[i] = new String(id3Data.data, startIndex, endIndex - startIndex, "ISO-8859-1");
+ int endIndex = indexOfZeroByte(id3Data.getData(), startIndex);
+ children[i] = new String(id3Data.getData(), startIndex, endIndex - startIndex, "ISO-8859-1");
  id3Data.setPosition(endIndex + 1);
  }
 
@@ -721,7 +723,7 @@ private static BinaryFrame decodeBinaryFrame(ParsableByteArray id3Data, int fram
  * @return The length of the data after processing.
  */
  private static int removeUnsynchronization(ParsableByteArray data, int length) {
- byte[] bytes = data.data;
+ byte[] bytes = data.getData();
  int startPosition = data.getPosition();
  for (int i = startPosition; i + 1 < startPosition + length; i++) {
  if ((bytes[i] & 0xFF) == 0xFF && bytes[i + 1] == 0x00) {

library/common/src/main/java/com/google/android/exoplayer2/util/ParsableBitArray.java

@@ -72,7 +72,7 @@ public void reset(byte[] data) {
  * @param parsableByteArray The {@link ParsableByteArray}.
  */
  public void reset(ParsableByteArray parsableByteArray) {
- reset(parsableByteArray.data, parsableByteArray.limit());
+ reset(parsableByteArray.getData(), parsableByteArray.limit());
  setPosition(parsableByteArray.getPosition() * 8);
  }
 

library/common/src/main/java/com/google/android/exoplayer2/util/ParsableByteArray.java

@@ -26,10 +26,8 @@
  */
 public final class ParsableByteArray {
 
- public byte[] data;
-
+ private byte[] data;
  private int position;
-
  // TODO(internal b/147657250): Enforce this limit on all read methods.
  private int limit;
 
@@ -138,13 +136,6 @@ public int getPosition() {
  return position;
  }
 
- /**
- * Returns the capacity of the array, which may be larger than the limit.
- */
- public int capacity() {
- return data.length;
- }
-
  /**
  * Sets the reading offset in the array.
  *
@@ -158,6 +149,23 @@ public void setPosition(int position) {
  this.position = position;
  }
 
+ /**
+ * Returns the underlying array.
+ *
+ * <p>Changes to this array are reflected in the results of the {@code read...()} methods.
+ *
+ * <p>This reference must be assumed to become invalid when {@link #reset} is called (because the
+ * array might get reallocated).
+ */
+ public byte[] getData() {
+ return data;
+ }
+
+ /** Returns the capacity of the array, which may be larger than the limit. */
+ public int capacity() {
+ return data.length;
+ }
+
  /**
  * Moves the reading offset by {@code bytes}.
  *

library/common/src/main/java/com/google/android/exoplayer2/util/Util.java

@@ -2046,14 +2046,14 @@ public static boolean inflate(
  if (input.bytesLeft() <= 0) {
  return false;
  }
- byte[] outputData = output.data;
+ byte[] outputData = output.getData();
  if (outputData.length < input.bytesLeft()) {
  outputData = new byte[2 * input.bytesLeft()];
  }
  if (inflater == null) {
  inflater = new Inflater();
  }
- inflater.setInput(input.data, input.getPosition(), input.bytesLeft());
+ inflater.setInput(input.getData(), input.getPosition(), input.bytesLeft());
  try {
  int outputSize = 0;
  while (true) {

library/common/src/main/java/com/google/android/exoplayer2/video/AvcConfig.java

@@ -91,7 +91,7 @@ private static byte[] buildNalUnitForChild(ParsableByteArray data) {
  int length = data.readUnsignedShort();
  int offset = data.getPosition();
  data.skipBytes(length);
- return CodecSpecificDataUtil.buildNalUnit(data.data, offset, length);
+ return CodecSpecificDataUtil.buildNalUnit(data.getData(), offset, length);
  }
 
 }

library/common/src/main/java/com/google/android/exoplayer2/video/HevcConfig.java

@@ -69,8 +69,8 @@ public static HevcConfig parse(ParsableByteArray data) throws ParserException {
  System.arraycopy(NalUnitUtil.NAL_START_CODE, 0, buffer, bufferPosition,
  NalUnitUtil.NAL_START_CODE.length);
  bufferPosition += NalUnitUtil.NAL_START_CODE.length;
- System
- .arraycopy(data.data, data.getPosition(), buffer, bufferPosition, nalUnitLength);
+ System.arraycopy(
+ data.getData(), data.getPosition(), buffer, bufferPosition, nalUnitLength);
  bufferPosition += nalUnitLength;
  data.skipBytes(nalUnitLength);
  }

library/common/src/test/java/com/google/android/exoplayer2/util/ParsableByteArrayTest.java

@@ -34,7 +34,7 @@ public final class ParsableByteArrayTest {
 
  private static ParsableByteArray getTestDataArray() {
  ParsableByteArray testArray = new ParsableByteArray(TEST_DATA.length);
- System.arraycopy(TEST_DATA, 0, testArray.data, 0, TEST_DATA.length);
+ System.arraycopy(TEST_DATA, 0, testArray.getData(), 0, TEST_DATA.length);
  return testArray;
  }
 
@@ -246,7 +246,7 @@ public void modificationsAffectParsableArray() {
  ParsableByteArray parsableByteArray = getTestDataArray();
 
  // When modifying the wrapped byte array
- byte[] data = parsableByteArray.data;
+ byte[] data = parsableByteArray.getData();
  long readValue = parsableByteArray.readUnsignedInt();
  data[0] = (byte) (TEST_DATA[0] + 1);
  parsableByteArray.setPosition(0);
@@ -259,7 +259,7 @@ public void readingUnsignedLongWithMsbSetThrows() {
  ParsableByteArray parsableByteArray = getTestDataArray();
 
  // Given an array with the most-significant bit set on the top byte
- byte[] data = parsableByteArray.data;
+ byte[] data = parsableByteArray.getData();
  data[0] = (byte) 0x80;
  // Then reading an unsigned long throws.
  try {
@@ -291,7 +291,7 @@ public void readingBytesReturnsCopy() {
  byte[] copy = new byte[length];
  parsableByteArray.readBytes(copy, 0, length);
  // Then the array elements are the same.
- assertThat(copy).isEqualTo(parsableByteArray.data);
+ assertThat(copy).isEqualTo(parsableByteArray.getData());
  }
 
  @Test

library/common/src/test/java/com/google/android/exoplayer2/util/UtilTest.java

@@ -873,7 +873,7 @@ public void inflate_withDeflatedData_success() {
  ParsableByteArray output = new ParsableByteArray();
  assertThat(Util.inflate(input, output, /* inflater= */ null)).isTrue();
  assertThat(output.limit()).isEqualTo(testData.length);
- assertThat(Arrays.copyOf(output.data, output.limit())).isEqualTo(testData);
+ assertThat(Arrays.copyOf(output.getData(), output.limit())).isEqualTo(testData);
  }
 
  // TODO: Revert to @Config(sdk = Config.ALL_SDKS) once b/143232359 is resolved

library/core/src/main/java/com/google/android/exoplayer2/source/SampleDataQueue.java

@@ -127,7 +127,7 @@ public void readToBuffer(DecoderInputBuffer buffer, SampleExtrasHolder extrasHol
  if (buffer.hasSupplementalData()) {
  // If there is supplemental data, the sample data is prefixed by its size.
  scratch.reset(4);
- readData(extrasHolder.offset, scratch.data, 4);
+ readData(extrasHolder.offset, scratch.getData(), 4);
  int sampleSize = scratch.readUnsignedIntToInt();
  extrasHolder.offset += 4;
  extrasHolder.size -= 4;
@@ -223,9 +223,9 @@ private void readEncryptionData(DecoderInputBuffer buffer, SampleExtrasHolder ex
 
  // Read the signal byte.
  scratch.reset(1);
- readData(offset, scratch.data, 1);
+ readData(offset, scratch.getData(), 1);
  offset++;
- byte signalByte = scratch.data[0];
+ byte signalByte = scratch.getData()[0];
  boolean subsampleEncryption = (signalByte & 0x80) != 0;
  int ivSize = signalByte & 0x7F;
 
@@ -244,7 +244,7 @@ private void readEncryptionData(DecoderInputBuffer buffer, SampleExtrasHolder ex
  int subsampleCount;
  if (subsampleEncryption) {
  scratch.reset(2);
- readData(offset, scratch.data, 2);
+ readData(offset, scratch.getData(), 2);
  offset += 2;
  subsampleCount = scratch.readUnsignedShort();
  } else {
@@ -263,7 +263,7 @@ private void readEncryptionData(DecoderInputBuffer buffer, SampleExtrasHolder ex
  if (subsampleEncryption) {
  int subsampleDataLength = 6 * subsampleCount;
  scratch.reset(subsampleDataLength);
- readData(offset, scratch.data, subsampleDataLength);
+ readData(offset, scratch.getData(), subsampleDataLength);
  offset += subsampleDataLength;
  scratch.setPosition(0);
  for (int i = 0; i < subsampleCount; i++) {

library/core/src/main/java/com/google/android/exoplayer2/text/pgs/PgsDecoder.java

@@ -72,7 +72,7 @@ private void maybeInflateData(ParsableByteArray buffer) {
  inflater = new Inflater();
  }
  if (Util.inflate(buffer, inflatedBuffer, inflater)) {
- buffer.reset(inflatedBuffer.data, inflatedBuffer.limit());
+ buffer.reset(inflatedBuffer.getData(), inflatedBuffer.limit());
  } // else assume data is not compressed.
  }
  }
@@ -183,7 +183,7 @@ private void parseBitmapSection(ParsableByteArray buffer, int sectionLength) {
  int limit = bitmapData.limit();
  if (position < limit && sectionLength > 0) {
  int bytesToRead = Math.min(sectionLength, limit - position);
- buffer.readBytes(bitmapData.data, position, bytesToRead);
+ buffer.readBytes(bitmapData.getData(), position, bytesToRead);
  bitmapData.setPosition(position + bytesToRead);
  }
  }

library/core/src/main/java/com/google/android/exoplayer2/text/webvtt/CssParser.java

@@ -78,7 +78,7 @@ public List<WebvttCssStyle> parseBlock(ParsableByteArray input) {
  stringBuilder.setLength(0);
  int initialInputPosition = input.getPosition();
  skipStyleBlock(input);
- styleInput.reset(input.data, input.getPosition());
+ styleInput.reset(input.getData(), input.getPosition());
  styleInput.setPosition(initialInputPosition);
 
  List<WebvttCssStyle> styles = new ArrayList<>();
@@ -154,7 +154,7 @@ private static String readCueTarget(ParsableByteArray input) {
  int limit = input.limit();
  boolean cueTargetEndFound = false;
  while (position < limit && !cueTargetEndFound) {
- char c = (char) input.data[position++];
+ char c = (char) input.getData()[position++];
  cueTargetEndFound = c == ')';
  }
  return input.readString(--position - input.getPosition()).trim();
@@ -267,7 +267,7 @@ private static boolean maybeSkipWhitespace(ParsableByteArray input) {
  }
 
  private static char peekCharAtPosition(ParsableByteArray input, int position) {
- return (char) input.data[position];
+ return (char) input.getData()[position];
  }
 
  @Nullable
@@ -297,7 +297,7 @@ private static String parsePropertyValue(ParsableByteArray input, StringBuilder
  private static boolean maybeSkipComment(ParsableByteArray input) {
  int position = input.getPosition();
  int limit = input.limit();
- byte[] data = input.data;
+ byte[] data = input.getData();
  if (position + 2 <= limit && data[position++] == '/' && data[position++] == '*') {
  while (position + 1 < limit) {
  char skippedChar = (char) data[position++];
@@ -320,7 +320,7 @@ private static String parseIdentifier(ParsableByteArray input, StringBuilder str
  int limit = input.limit();
  boolean identifierEndFound = false;
  while (position < limit && !identifierEndFound) {
- char c = (char) input.data[position];
+ char c = (char) input.getData()[position];
  if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '#'
  || c == '-' || c == '.' || c == '_') {
  position++;

library/core/src/main/java/com/google/android/exoplayer2/text/webvtt/Mp4WebvttDecoder.java

@@ -84,7 +84,7 @@ private static Cue parseVttCueBox(ParsableByteArray sampleData, int remainingCue
  remainingCueBoxBytes -= BOX_HEADER_SIZE;
  int payloadLength = boxSize - BOX_HEADER_SIZE;
  String boxPayload =
- Util.fromUtf8Bytes(sampleData.data, sampleData.getPosition(), payloadLength);
+ Util.fromUtf8Bytes(sampleData.getData(), sampleData.getPosition(), payloadLength);
  sampleData.skipBytes(payloadLength);
  remainingCueBoxBytes -= payloadLength;
  if (boxType == TYPE_sttg) {

library/core/src/main/java/com/google/android/exoplayer2/video/spherical/ProjectionDecoder.java

@@ -179,7 +179,7 @@ private static boolean isProj(ParsableByteArray input) {
  final double log2 = Math.log(2.0);
  int coordinateCountSizeBits = (int) Math.ceil(Math.log(2.0 * coordinateCount) / log2);
 
- ParsableBitArray bitInput = new ParsableBitArray(input.data);
+ ParsableBitArray bitInput = new ParsableBitArray(input.getData());
  bitInput.setPosition(input.getPosition() * 8);
  float[] vertices = new float[vertexCount * 5];
  int[] coordinateIndices = new int[5];

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/FlacFrameReader.java

@@ -107,10 +107,11 @@ public static boolean checkFrameHeaderFromPeek(
 
  ParsableByteArray scratch = new ParsableByteArray(FlacConstants.MAX_FRAME_HEADER_SIZE);
  System.arraycopy(
- frameStartBytes, /* srcPos= */ 0, scratch.data, /* destPos= */ 0, /* length= */ 2);
+ frameStartBytes, /* srcPos= */ 0, scratch.getData(), /* destPos= */ 0, /* length= */ 2);
 
  int totalBytesPeeked =
- ExtractorUtil.peekToLength(input, scratch.data, 2, FlacConstants.MAX_FRAME_HEADER_SIZE - 2);
+ ExtractorUtil.peekToLength(
+ input, scratch.getData(), 2, FlacConstants.MAX_FRAME_HEADER_SIZE - 2);
  scratch.setLimit(totalBytesPeeked);
 
  input.resetPeekPosition();
@@ -145,7 +146,7 @@ public static long getFirstSampleNumber(
  int maxUtf8SampleNumberSize = isBlockSizeVariable ? 7 : 6;
  ParsableByteArray scratch = new ParsableByteArray(maxUtf8SampleNumberSize);
  int totalBytesPeeked =
- ExtractorUtil.peekToLength(input, scratch.data, 0, maxUtf8SampleNumberSize);
+ ExtractorUtil.peekToLength(input, scratch.getData(), 0, maxUtf8SampleNumberSize);
  scratch.setLimit(totalBytesPeeked);
  input.resetPeekPosition();
 
@@ -325,7 +326,7 @@ private static boolean checkAndReadCrc(ParsableByteArray data, int frameStartPos
  int crc = data.readUnsignedByte();
  int frameEndPosition = data.getPosition();
  int expectedCrc =
- Util.crc8(data.data, frameStartPosition, frameEndPosition - 1, /* initialValue= */ 0);
+ Util.crc8(data.getData(), frameStartPosition, frameEndPosition - 1, /* initialValue= */ 0);
  return crc == expectedCrc;
  }