kennywest

On a past project, users needed to be able to create a custom query and execute it. To do this, the user was able to select a field, an operator and select or fill in a value. If, for example, we were searching for people living in Belgium, the user would select person.address.country for the field, like for the operator and fill in "BE" for the value. I'm sure you all know how the resulting SQL would look like. There are different ways to create a query builder. If you're using Hibernate , the above example could easily be translated to HQL using the criteria API. In some cases, however, the resulting SQL is not exactly what you wanted (e.g. not performing well) or maybe Hibernate is just not capable generating a correct SQL. Unfortunately, at that time, we discovered we were suffering both aforementioned problems, so the only solution was to create our own query builders using string concatenation. Yes, this can get ugly really fast, when not being careful, but I...

We're developing a fairly large application in Java. There are 2 front end applications, one written in Flex, the other in plain Spring-MVC and Spring-WebFlow. Both of them are using 3 main applications deployed as 3 different wars on the same application server. The front end applications talk with the back end applications using RMI exposed as HTTP. The back end applications also talk to each other using the same protocol. One of the applications deployed in the back end is responsible for validating data entered in the front end applications. One of the rules in the, so called ValidationService, checks if the SSIN of a person is valid. In Belgium, all people have a unique SSIN (Social Security Identification Number), comprised of 11 digits. The first 6 digits are based on the person's birth date. So if this person was born on April 21, 1978, the SSIN starts with 780421xxxyy. To check if an SSIN is valid, you need to check the person's birth date against these first 6 dig...