Java Code Examples for io.airlift.slice.Slice#setLong()

@Description("Encode value as a 64-bit 2's complement big endian varbinary")
@ScalarFunction("to_big_endian_64")
@SqlType(StandardTypes.VARBINARY)
public static Slice toBigEndian64(@SqlType(StandardTypes.BIGINT) long value)
{
    Slice slice = Slices.allocate(Long.BYTES);
    slice.setLong(0, Long.reverseBytes(value));
    return slice;
}
 

@Description("Encode value as a big endian varbinary according to IEEE 754 double-precision floating-point format")
@ScalarFunction("to_ieee754_64")
@SqlType(StandardTypes.VARBINARY)
public static Slice toIEEE754Binary64(@SqlType(StandardTypes.DOUBLE) double value)
{
    Slice slice = Slices.allocate(Double.BYTES);
    slice.setLong(0, Long.reverseBytes(Double.doubleToLongBits(value)));
    return slice;
}
 

@Description("Compute xxhash64 hash")
@ScalarFunction
@SqlType(StandardTypes.VARBINARY)
public static Slice xxhash64(@SqlType(StandardTypes.VARBINARY) Slice slice)
{
    Slice hash = Slices.allocate(Long.BYTES);
    hash.setLong(0, Long.reverseBytes(XxHash64.hash(slice)));
    return hash;
}
 

@Description("Compute SpookyHashV2 64-bit hash")
@ScalarFunction
@SqlType(StandardTypes.VARBINARY)
public static Slice spookyHashV2_64(@SqlType(StandardTypes.VARBINARY) Slice slice)
{
    Slice hash = Slices.allocate(Long.BYTES);
    hash.setLong(0, Long.reverseBytes(SpookyHashV2.hash64(slice, 0, slice.length(), 0)));
    return hash;
}
 

/**
 * Serializes the model using the following format
 * int: format version
 * byte[32]: SHA256 hash of all following data
 * int: id of algorithm
 * int: length of hyperparameters section
 * byte[]: hyperparameters (currently not used)
 * long: length of data section
 * byte[]: model data
 * <p>
 * note: all multibyte values are in little endian
 */
public static Slice serialize(Model model)
{
    requireNonNull(model, "model is null");
    Integer id = MODEL_SERIALIZATION_IDS.get(model.getClass());
    requireNonNull(id, "id is null");
    int size = HYPERPARAMETERS_OFFSET;

    // hyperparameters aren't implemented yet
    byte[] hyperparameters = new byte[0];
    size += hyperparameters.length;

    int dataLengthOffset = size;
    size += SIZE_OF_LONG;
    int dataOffset = size;
    byte[] data = model.getSerializedData();
    size += data.length;

    Slice slice = Slices.allocate(size);
    slice.setInt(VERSION_OFFSET, CURRENT_FORMAT_VERSION);
    slice.setInt(ALGORITHM_OFFSET, id);
    slice.setInt(HYPERPARAMETER_LENGTH_OFFSET, hyperparameters.length);
    slice.setBytes(HYPERPARAMETERS_OFFSET, hyperparameters);
    slice.setLong(dataLengthOffset, data.length);
    slice.setBytes(dataOffset, data);

    byte[] modelHash = Hashing.sha256().hashBytes(slice.getBytes(ALGORITHM_OFFSET, slice.length() - ALGORITHM_OFFSET)).asBytes();
    checkState(modelHash.length == 32, "sha256 hash code expected to be 32 bytes");
    slice.setBytes(HASH_OFFSET, modelHash);

    return slice;
}
 

public static void pack(long low, long high, boolean negative, Slice result, int resultOffset)
{
    result.setLong(resultOffset, low);

    long value = high | (negative ? SIGN_LONG_MASK : 0);
    result.setLong(resultOffset + SIZE_OF_LONG, value);
}
 

public Slice getSync()
{
    Slice sync = Slices.allocate(SIZE_OF_LONG + SIZE_OF_LONG);
    sync.setLong(0, syncFirst);
    sync.setLong(SIZE_OF_LONG, syncSecond);
    return sync;
}
 

private static byte[] toParquetEncoding(Instant timestamp)
{
    long startOfDay = LocalDate.ofInstant(timestamp, ZoneOffset.UTC).atStartOfDay().toInstant(ZoneOffset.UTC).toEpochMilli();
    long timeOfDayNanos = (long) ((timestamp.toEpochMilli() - startOfDay) * Math.pow(10, 6));

    Slice slice = Slices.allocate(12);
    slice.setLong(0, timeOfDayNanos);
    slice.setInt(8, millisToJulianDay(timestamp.toEpochMilli()));
    return slice.byteArray();
}
 

private static void setRawLong(Slice decimal, int index, long value)
{
    decimal.setLong(SIZE_OF_LONG * index, value);
}