Reads the byte at this buffer's current position, and then increments the position.
Throws:
BufferOverflowException
int get nextByte { return _getId(this, const jbyteType(), []); }
Writes the given byte into this buffer at the current position, and then increments the position.
ReadOnlyBufferException
set nextByte(int b) { _putId(this, const JObjectType(), [JValueByte(b)]).release(); }