code: public static String[] getOperatorsForAttributeType(AbstractReadOnlyAttributeInfo attributeInfo) {
  		if (attributeInfo != null && attributeInfo instanceof PrimitiveAttributeInfo) {
  			PrimitiveAttributeInfo primitive = (PrimitiveAttributeInfo) attributeInfo;
  			switch (primitive.getType()) {
  				case SHORT:
  				case INTEGER:
  				case LONG:
  				case FLOAT:
  				case DOUBLE:
  				case CURRENCY:
  					return new String[] { I18nProvider.getSearch().operatorEquals(),
  							I18nProvider.getSearch().operatorNotEquals(), I18nProvider.getSearch().operatorST(),
  							I18nProvider.getSearch().operatorSE(), I18nProvider.getSearch().operatorBT(),
  							I18nProvider.getSearch().operatorBE() };
  				case DATE:
  					return new String[] { I18nProvider.getSearch().operatorEquals(),
  							I18nProvider.getSearch().operatorBefore(), I18nProvider.getSearch().operatorAfter() };
  				case STRING:
  				case URL:
  				case IMGURL:
  					return new String[] { I18nProvider.getSearch().operatorContains(),
  							I18nProvider.getSearch().operatorEquals(), I18nProvider.getSearch().operatorNotEquals() };
  				case BOOLEAN:
  				default:
  					return new String[] { I18nProvider.getSearch().operatorEquals(),
  							I18nProvider.getSearch().operatorNotEquals() };
  			}
  		}
  		return new String[] { I18nProvider.getSearch().operatorEquals(), I18nProvider.getSearch().operatorNotEquals() };
  	}
docs: Static method that return an array of available operator labels for the given attribute definition. An operator
  label is something like "is equal to". Don't confuse this with the operator code (something like "=").
  
  @param attributeInfo
  The attribute definition for which to return possible operators.
  @return operators