code: public static InputStream fromFile(String filepath) throws FileNotFoundException {
  		if(Strings.isValid(filepath)) {
  			return fromFile(new File(filepath));
  		}
  		return null;
  	}
docs: Returns an input stream from a string representing its path.
  
  @param filepath
  a string representing the file path.
  @return
  a {@code FileInputStream} object.
  @throws FileNotFoundException