What's the best way to unit test a cfc that uses a Java object for a lot of its functionality?

I have a cfc that relies heavily on a Java object (created via JavaLoader) for a lot of its core functionality that I'd like to write some tests for and I'm not sure what the best way to do this is. Here is an example of a method I'd like to write a test for with instance.note being a java object.

<cffunction name="getNotes" returntype="Array" access="public" output="false" hint="I return a list of a users notebooks" >
    <cfargument name="maxCount" type="numeric" required="false" default="9999" hint="The maximum number of notes to get" />
    <cfscript>
        if(arguments.maxCount)
            return instance.note.listNotes(maxCount);
        else
            return instance.note.listNotes();
    </cfscript>
</cffunction>

One thing I thought of doing is creating a stub CFC that has the same method names and similar return values and then mocking that stub and injecting it?

Solution

When we needed to unit test CF functions that relied upon Java objects (which we did a LOT of), we used Mockito to mock the Java objects.

So, hoping this code snippet makes sense, its been almost a year since I've done this:

<cfcomponent displayname="TestWhatever" extends="mxunit.framework.TestCase" output="false">

    <cffunction name="setUp" access="public" returntype="void">
      <cfscript>
        // named it mk for keeping it short
        variables.mk = createObject("java","org.mockito.Mockito");

        //Create the mock object
        variables.mockNote = mk.mock(createObject("java","com.company.whatever.note").getClass());

        // Mock Data
        fullList = {whatever listNotes() returns}
        partialList3 = {whatever listNotes(3) returns}

        //some common mocking
        mk.when(variables.mockNote.listNotes()).thenReturn(fullList);
        mk.when(variables.mockNote.listNotes(mk.eq(3))).thenReturn(partialList3);
        mk.when(variables.rootOrgObj.guid()).thenReturn("root");

        // Assign the mock object to where your CFC expects it.
        instance.note = variables.mockNote
      </cfscript>
    </cffunction>

</cfcomponent>

Having said that, if your sample function is real, there's really no point in unit testing it. Its simply not doing anything but being a proxy to the java object. There is no significant logic in there to test.

Since you have a default on the cfargument, it will always exist (again, I think so, its been a year since I've done CF), so your guard statement isn't even required - the first code path will always be called, with the passed maxCount if specified, or with 9999 if not.