public boolean shouldInvertSign()

in harry-core/src/harry/generators/DataGenerators.java [390:428]

• 25 lines of code
• 5 McCabe index (conditional complexity)

        public boolean shouldInvertSign(int idx)
        {
            Bijections.Bijection<?> gen = columns.get(idx).generator();

            int maxSliceSize = gen.byteSize();
            int actualSliceSize = sizes[idx];


            if (idx == 0)
            {
                // We consume a sign of a descriptor (long, long), (int, int), etc.
                if (totalSize == Long.BYTES)
                {
                    // If we use only 3 bytes for a 4-byte int, or 4 bytes for a 8-byte int,
                    // they're effectively unsigned/byte-ordered, so their order won't match
                    if (maxSliceSize > actualSliceSize)
                        return true;
                    // Sign of the current descriptor should match the sign of the slice.
                    // For example, (tinyint, double) or (double, tinyint). In the first case (tinyint first),
                    // sign of the first component is going to match the sign of the descriptor.
                    // In the second case (double first), double is 7-bit, but its most significant bit
                    // does not hold a sign, so we have to invert it to match sign of the descriptor.
                    else
                        return gen.unsigned();
                }
                // We do not consume a sign of a descriptor (float, tinyint), (int, tinyint), etc,
                // so we have to only invert signs of the values, since their order doesn't match.
                else
                {
                    assert maxSliceSize == actualSliceSize;
                    return !gen.unsigned();
                }
            }
            else if (gen.unsigned())
                return false;
            else
                // We invert sign of all subsequent chunks if they have enough entropy to have a sign bit set
                return maxSliceSize == actualSliceSize;
        }