public void writeByte(int position,byte b){
  if (position < 0 || position >= Page.pageSize) {
    throw new PageException("readByte is out of bounds of page");
  }
  pageData.put(position,b);
}

public void writeByte ( int position , byte b ) { if ( position < 0 || position >= Page . pageSize ) { throw new PageException ( "readByte is out of bounds of page" ) ; } pageData . put ( position , b ) ; }
write a single byte into the file at offset position .
