I recently modified Hadoop’s BytesWritable. The reason is that I developed BinaryInputOutputFormat. It has the LongWritable file offset as key and BytesWritable record as value. I parsed BytesWritable record in Map function using method, value.getBytes(). And then in the reduce phase I tried to sum that value up. But sum count boundary is to small (that size is as long as byte array length). So I overload the ByteWritable’s set method. The argument is set(byte array, byte array offset, int length). I modifiey the method is set(byte array, byteswritable’s start offset, byte array offset, int length). But I wondered BytesWritable’s setCapacity() method. Why in the method, set the capacity longer than
