code: public T withWebapp(File webapp) {
  		notNull(webapp, "webapp");
  		this.webapp = webapp.getAbsolutePath();
  		return self();
  	}
docs: Change {@link #webapp} value.
  
  @param webapp New {@link #webapp} value (the absolute path will be used).
  @return this
  @throws NullPointerException If {@code webapp} is null.