Sebastian S. Sebastian S. - 1 month ago 26
Java Question

Spring data JPA and parameters that can be null

My understanding is, that with Spring data JPA I cannot have a query method to fetch all rows where a column equals a given non-null method parameter and use the same method to fetch all rows where this column is NULL when the method parameter is null.

Is that correct?

So I have to distinguish this in my JAVA code and I must use a separate query method explicitly asking for null values, like in the example below?

// Query methods
List<Something> findByParameter(Parameter parameter);
List<Something> findByParameterIsNull();

...

List<Something> result = new ArrayList<>();

if (parameter == null)
result = findByParameterIsNull();
else
result = findByParameter(parameter);


That's bad, if I have 4 parameters which could be null and would have to code 16 different query methods.

Answer

You are right.

A request has been made to support better handling of null parameters. https://jira.spring.io/browse/DATAJPA-121

In your case, i would advise you to write your repository implementation and to use a custom CriteriaQuery to handle your case.

Alternatively (not tested), you could use a @Query something like : (:parameter is null or parameter = :parameter)