Class Utf8.UnsafeProcessor

java.lang.Object
com.google.protobuf.Utf8.Processor
com.google.protobuf.Utf8.UnsafeProcessor
Enclosing class:
Utf8

static final class Utf8.UnsafeProcessor extends Utf8.Processor
Utf8.Processor that uses sun.misc.Unsafe where possible to improve performance.
  • Constructor Details

    • UnsafeProcessor

      UnsafeProcessor()
  • Method Details

    • isAvailable

      static boolean isAvailable()
      Indicates whether or not all required unsafe operations are supported on this platform.
    • partialIsValidUtf8

      int partialIsValidUtf8(int state, byte[] bytes, int index, int limit)
      Description copied from class: Utf8.Processor
      Tells whether the given byte array slice is a well-formed, malformed, or incomplete UTF-8 byte sequence. The range of bytes to be checked extends from index index, inclusive, to limit, exclusive.
      Specified by:
      partialIsValidUtf8 in class Utf8.Processor
      Parameters:
      state - either Utf8.COMPLETE (if this is the initial decoding operation) or the value returned from a call to a partial decoding method for the previous bytes
      Returns:
      Utf8.MALFORMED if the partial byte sequence is definitely not well-formed, Utf8.COMPLETE if it is well-formed (no additional input needed), or if the byte sequence is "incomplete", i.e. apparently terminated in the middle of a character, an opaque integer "state" value containing enough information to decode the character when passed to a subsequent invocation of a partial decoding method.
    • partialIsValidUtf8Direct

      int partialIsValidUtf8Direct(int state, ByteBuffer buffer, int index, int limit)
      Description copied from class: Utf8.Processor
      Performs validation for direct ByteBuffer instances.
      Specified by:
      partialIsValidUtf8Direct in class Utf8.Processor
    • decodeUtf8

      String decodeUtf8(byte[] bytes, int index, int size) throws InvalidProtocolBufferException
      Description copied from class: Utf8.Processor
      Decodes the given byte array slice into a String.
      Specified by:
      decodeUtf8 in class Utf8.Processor
      Throws:
      InvalidProtocolBufferException - if the byte array slice is not valid UTF-8
    • decodeUtf8Direct

      String decodeUtf8Direct(ByteBuffer buffer, int index, int size) throws InvalidProtocolBufferException
      Description copied from class: Utf8.Processor
      Decodes direct ByteBuffer instances into String.
      Specified by:
      decodeUtf8Direct in class Utf8.Processor
      Throws:
      InvalidProtocolBufferException
    • encodeUtf8

      int encodeUtf8(String in, byte[] out, int offset, int length)
      Description copied from class: Utf8.Processor
      Encodes an input character sequence (in) to UTF-8 in the target array (out). For a string, this method is similar to
      
       byte[] a = string.getBytes(UTF_8);
       System.arraycopy(a, 0, bytes, offset, a.length);
       return offset + a.length;
       
      but is more efficient in both time and space. One key difference is that this method requires paired surrogates, and therefore does not support chunking. While String.getBytes(UTF_8) replaces unpaired surrogates with the default replacement character, this method throws Utf8.UnpairedSurrogateException.

      To ensure sufficient space in the output buffer, either call Utf8.encodedLength(java.lang.String) to compute the exact amount needed, or leave room for Utf8.MAX_BYTES_PER_CHAR * sequence.length(), which is the largest possible number of bytes that any input can be encoded to.

      Specified by:
      encodeUtf8 in class Utf8.Processor
      Parameters:
      in - the input character sequence to be encoded
      out - the target array
      offset - the starting offset in bytes to start writing at
      length - the length of the bytes, starting from offset
      Returns:
      the new offset, equivalent to offset + Utf8.encodedLength(sequence)
    • encodeUtf8Direct

      void encodeUtf8Direct(String in, ByteBuffer out)
      Description copied from class: Utf8.Processor
      Encodes the input character sequence to a direct ByteBuffer instance.
      Specified by:
      encodeUtf8Direct in class Utf8.Processor
    • unsafeEstimateConsecutiveAscii

      private static int unsafeEstimateConsecutiveAscii(byte[] bytes, long offset, int maxChars)
      Counts (approximately) the number of consecutive ASCII characters starting from the given position, using the most efficient method available to the platform.
      Parameters:
      bytes - the array containing the character sequence
      offset - the offset position of the index (same as index + arrayBaseOffset)
      maxChars - the maximum number of characters to count
      Returns:
      the number of ASCII characters found. The stopping position will be at or before the first non-ASCII byte.
    • unsafeEstimateConsecutiveAscii

      private static int unsafeEstimateConsecutiveAscii(long address, int maxChars)
      Same as Utf8.estimateConsecutiveAscii(ByteBuffer, int, int) except that it uses the most efficient method available to the platform.
    • partialIsValidUtf8

      private static int partialIsValidUtf8(byte[] bytes, long offset, int remaining)
    • partialIsValidUtf8

      private static int partialIsValidUtf8(long address, int remaining)
    • unsafeIncompleteStateFor

      private static int unsafeIncompleteStateFor(byte[] bytes, int byte1, long offset, int remaining)
    • unsafeIncompleteStateFor

      private static int unsafeIncompleteStateFor(long address, int byte1, int remaining)