public FilePath(String path){
  path=path.trim();
  if (path.startsWith("/"))   absolute=true;
 else   absolute=false;
  append(path);
}

public FilePath ( String path ) { path = path . trim ( ) ; if ( path . startsWith ( "/" ) ) absolute = true ; else absolute = false ; append ( path ) ; }
constructs a path from a string , which may be a full or partial path .
