code: public void addContextParam(final WebAppInitParam contextParam) {
  		NullArgumentException.validateNotNull(contextParam, "Context param");
  		NullArgumentException.validateNotNull(contextParam.getParamName(),
  				"Context param name");
  		NullArgumentException.validateNotNull(contextParam.getParamValue(),
  				"Context param value");
  		contextParams.add(contextParam);
  	}
docs: Add a context param.
  
  @param contextParam to add
  @throws NullArgumentException if context param, param name or param value is null