private boolean isSingleValueRestrictionType() {
		return this.restrictionType.equals(RestrictionType.EQUAL) ||
			   this.restrictionType.equals(RestrictionType.NOT_EQUAL) ||
			   this.restrictionType.equals(RestrictionType.GREATER) ||
			   this.restrictionType.equals(RestrictionType.GREATER_EQUAL) ||
			   this.restrictionType.equals(RestrictionType.LESSER) ||
			   this.restrictionType.equals(RestrictionType.LESSER_EQUAL) ||
			   this.restrictionType.equals(RestrictionType.LIKE) ||
			   this.restrictionType.equals(RestrictionType.LIKE_WITH_POSTFIX) ||
			   this.restrictionType.equals(RestrictionType.LIKE_WITH_PREFIX);
	}