@Override
                public void mergeFrom(Input input, T message)
                        throws IOException
                {
                    if (primitive)
                        us.putLong(message, offset, input.readInt64());
                    else
                        us.putObject(message, offset,
                                Long.valueOf(input.readInt64()));
                }
Field factory via sun.misc.Unsafe.

@author David Yu
@created Jul 7, 2011
protostuff-runtime/src/main/java/io/protostuff/runtime/RuntimeUnsafeFieldFactory.java