code: public void setLogicalOperator(LogicalOperator operator) {
  		switch (operator) {
  			case AND:
  				logicalOperatorRadio.setValue(I18nProvider.getSearch().radioOperatorAnd());
  				break;
  			case OR:
  				logicalOperatorRadio.setValue(I18nProvider.getSearch().radioOperatorOr());
  				break;
  			default:
  				throw new IllegalStateException("Unknown operator " + operator);
  		}
  	}
docs: Set a new value for the logical operator. This operator determines whether all the criteria have to be met in the
  search, or just one of them.
  
  @param operator logical operator