Finally, I am giving a try to the new feature of dynamic filters in Hibernate3.

But I have realized that when setting the parameters for the filter, the fact that a filter will not be used is done by simply not setting its parameter. For example:

<filter-def name="filterName">
<filter-param name="likeName" type="string" />
</filter-def>
<filter-def name="filterSurname">
<filter-param name="likeSurname" type="string" />
</filter-def>

And then in code:

session.enableFilter("filterName").setParameter("likeName", "%John%");
session.enableFilter("filterSurname").setParameter("likeSurname", "%Doe%");

So if I don't have a value for, imagine, surname, then I just have to omit the:

session.enableFilter("filterSurname").setParameter("likeSurname", "%Doe%");

But this will lead to having a bunch of if statements asking for the possible values of the parameters, won't it?:

if (IHaveValueForName)
session.enableFilter("filterName").setParameter("likeName", "%John%");
if (IHaveValueForSurname)
session.enableFilter("filterSurname").setParameter("likeSurname", "%Doe%");

Wouldn't it be easier just to set the parameter always, so if it is null then Hibernate just ignores it? For example:

session.enableFilter("filterName").setParameter("likeName", "%John%");
session.enableFilter("filterSurname").setParameter("likeSurname", null);

Because this doesn't work :-(, as Hibernate throws the following exception:

java.lang.IllegalArgumentException: Filter [filterSurname] defined parameter [likeSurname] whose value was not set

Maybe you should create many filters with each a single attribute and enable it only when the parameter is provided.