Package org.apache.cassandra.utils.bytecomparable

Interface ByteSource

All Known Implementing Classes:
ByteSource.AbstractEscaper, ByteSource.AccessorEscaper, ByteSource.ArrayEscaper, ByteSource.BufferEscaper, ByteSource.MemoryEscaper, ByteSource.Multi, ByteSource.Number, ByteSource.Peekable, ByteSource.Separator, ByteSource.SignedFixedLengthFloat, ByteSource.SignedFixedLengthNumber, ByteSource.VariableLengthInteger, ByteSource.VariableLengthUnsignedInteger
public interface ByteSource
A stream of bytes, used for byte-order-comparable representations of data, and utilities to convert various values to their byte-ordered translation. See ByteComparable.md for details about the encoding scheme.

  • Field Details

  • Method Details

    • next

      int next()
      Consume the next byte, unsigned. Must be between 0 and 255, or END_OF_STREAM if there are no more bytes.

    • of

      static <V> ByteSource of(ValueAccessor<V> accessor, V data, ByteComparable.Version version)
      Encodes byte-accessible data as a byte-comparable source that has 0s escaped and finishes in an escaped state. This provides a weakly-prefix-free byte-comparable version of the content to use in sequences. (See ByteSource.AbstractEscaper for a detailed explanation.)

    • of

      static ByteSource of(ByteBuffer buf, ByteComparable.Version version)
      Encodes a byte buffer as a byte-comparable source that has 0s escaped and finishes in an escape. This provides a weakly-prefix-free byte-comparable version of the content to use in sequences. (See ByteSource.BufferEscaper/Multi for explanation.)

    • of

      static ByteSource of(byte[] buf, ByteComparable.Version version)
      Encodes a byte array as a byte-comparable source that has 0s escaped and finishes in an escape. This provides a prefix-free byte-comparable version of the content to use in sequences. (See ByteSource.BufferEscaper/Multi for explanation.)

    • ofMemory

      static ByteSource ofMemory(long address, int length, ByteComparable.Version version)
      Encodes a memory range as a byte-comparable source that has 0s escaped and finishes in an escape. This provides a weakly-prefix-free byte-comparable version of the content to use in sequences. (See ByteSource.BufferEscaper/Multi for explanation.)

    • withTerminator

      static ByteSource withTerminator(int terminator, ByteSource... srcs)
      Combines a chain of sources, turning their weak-prefix-free byte-comparable representation into the combination's prefix-free byte-comparable representation, with the included terminator character. For correctness, the terminator must be within MIN-MAX_SEPARATOR and outside the range reserved for NEXT_COMPONENT markers. Typically TERMINATOR, or LT/GT_NEXT_COMPONENT if used for partially specified bounds.

    • withTerminatorLegacy

      static ByteSource withTerminatorLegacy(int terminator, ByteSource... srcs)
      As above, but permits any separator. The legacy format wasn't using weak prefix freedom and has some non-reversible transformations.

    • withTerminatorMaybeLegacy

      static ByteSource withTerminatorMaybeLegacy(ByteComparable.Version version, int legacyTerminator, ByteSource... srcs)

    • of

      static ByteSource of(String s, ByteComparable.Version version)

    • of

      static ByteSource of(long value)

    • of

      static ByteSource of(int value)

    • optionalSignedFixedLengthNumber

      static <V> ByteSource optionalSignedFixedLengthNumber(ValueAccessor<V> accessor, V data)
      Produce a source for a signed fixed-length number, also translating empty to null. The first byte has its sign bit inverted, and the rest are passed unchanged. Presumes that the length of the buffer is always either 0 or constant for the type, which permits decoding and ensures the representation is prefix-free.

    • signedFixedLengthNumber

      static <V> ByteSource signedFixedLengthNumber(ValueAccessor<V> accessor, V data)
      Produce a source for a signed fixed-length number. The first byte has its sign bit inverted, and the rest are passed unchanged. Presumes that the length of the buffer is always constant for the type.

    • optionalSignedFixedLengthFloat

      static <V> ByteSource optionalSignedFixedLengthFloat(ValueAccessor<V> accessor, V data)
      Produce a source for a signed fixed-length floating-point number, also translating empty to null. If sign bit is on, returns negated bytes. If not, add the sign bit value. (Sign of IEEE floats is the highest bit, the rest can be compared in magnitude by byte comparison.) Presumes that the length of the buffer is always either 0 or constant for the type, which permits decoding and ensures the representation is prefix-free.

    • signedFixedLengthFloat

      static <V> ByteSource signedFixedLengthFloat(ValueAccessor<V> accessor, V data)
      Produce a source for a signed fixed-length floating-point number. If sign bit is on, returns negated bytes. If not, add the sign bit value. (Sign of IEEE floats is the highest bit, the rest can be compared in magnitude by byte comparison.) Presumes that the length of the buffer is always constant for the type.

    • variableLengthInteger

      static ByteSource variableLengthInteger(long value)
      Produce a source for a signed integer, stored using variable length encoding. The representation uses between 1 and 9 bytes, is prefix-free and compares correctly.

    • separatorPrefix

      static ByteSource separatorPrefix(ByteSource prevMax, ByteSource currMin)
      Returns a separator for two byte sources, i.e. something that is definitely > prevMax, and <= currMin, assuming prevMax < currMin. This returns the shortest prefix of currMin that is greater than prevMax.

    • separatorGt

      static ByteSource separatorGt(ByteSource prevMax, ByteSource currMin)
      Returns a separator for two byte sources, i.e. something that is definitely > prevMax, and <= currMin, assuming prevMax < currMin. This is a source of length 1 longer than the common prefix of the two sources, with last byte one higher than the prevMax source.

    • oneByte

      static ByteSource oneByte(int i)

    • cut

      static ByteSource cut(ByteSource src, int cutoff)

    • cutOrRightPad

      static ByteSource cutOrRightPad(ByteSource src, int cutoff, int padding)
      Wrap a ByteSource in a length-fixing facade. If the length of src is less than cutoff, then pad it on the right with padding until the overall length equals cutoff. If the length of src is greater than cutoff, then truncate src to that size. Effectively a noop if src happens to have length cutoff.
      Parameters:
      src - the input source to wrap
      cutoff - the size of the source returned
      padding - a padding byte (an int subject to a 0xFF mask)

    • optionalFixedLength

      static <V> ByteSource optionalFixedLength(ValueAccessor<V> accessor, V data)

    • fixedLength

      static <V> ByteSource fixedLength(ValueAccessor<V> accessor, V data)
      A byte source of the given bytes without any encoding. The resulting source is only guaranteed to give correct comparison results and be prefix-free if the underlying type has a fixed length. In tests, this method is also used to generate non-escaped test cases.

    • fixedLength

      static ByteSource fixedLength(ByteBuffer b)
      A byte source of the given bytes without any encoding. The resulting source is only guaranteed to give correct comparison results and be prefix-free if the underlying type has a fixed length. In tests, this method is also used to generate non-escaped test cases.

    • fixedLength

      static ByteSource fixedLength(byte[] b)
      A byte source of the given bytes without any encoding. If used in a sequence, the resulting source is only guaranteed to give correct comparison results if the underlying type has a fixed length. In tests, this method is also used to generate non-escaped test cases.

    • fixedLength

      static ByteSource fixedLength(byte[] b, int offset, int length)

    • peekable

      static ByteSource.Peekable peekable(ByteSource p)