code: private void addClientOnlyExamples() {
  		// client command button
  
  		add(new WHeading(HeadingLevel.H2, "Client command buttons"));
  		add(new ExplanatoryText("These examples show buttons which do not submit the form"));
  
  		//client command buttons witho a command
  		WButton nothingButton = new WButton("Do nothing");
  		add(nothingButton);
  		nothingButton.setClientCommandOnly(true);
  		nothingButton = new WButton("Do nothing link");
  		add(nothingButton);
  		nothingButton.setRenderAsLink(true);
  		nothingButton.setClientCommandOnly(true);
  
  		// client command buttons with command.
  		HelloButton helloButton = new HelloButton("Hello");
  		add(helloButton);
  		helloButton = new HelloButton("Hello link");
  		helloButton.setRenderAsLink(true);
  		add(helloButton);
  	}
docs: Examples showing use of client only buttons.