Validating a record Id in Salesforce from a String

Utils.cls

public class Utils {
	static Boolean validId(String recordIdString) {
		try {
			Id recordId = (Id)recordIdString;
			String sobjectName = String.valueOf(recordId.getSObjectType());
			return Database.countQuery('SELECT COUNT() FROM '+sobjectName+' WHERE Id = :recordId') > 0;
		} catch(Exception e) {
			return false;
		}
	}
}