code: public UriComponentsBuilder port(int port) {
  		Assert.isTrue(port >= -1, "'port' must not be < -1");
  		this.port = String.valueOf(port);
  		resetSchemeSpecificPart();
  		return this;
  	}
docs: Set the URI port. Passing {@code -1} will clear the port of this builder.
  @param port the URI port
  @return this UriComponentsBuilder