Question

I have this method in a Directory model:

public List<Directory> subdirectories() {
    return find("select d from Directory d where d.parent = ?", this.id).fetch()
}

And this test:

@Test
public void testSubdirectories() {
    Directory d1 = Directory.find("byName", "d1").first();
    Directory d2 = Directory.find("byName", "d2").first();
    Directory d3 = Directory.find("byName", "d3").first();
    Directory d4 = Directory.find("byName", "d4").first();

    List<Directory> d1subs = d1.subdirectories();
    List<Directory> d2subs = d2.subdirectories();
    List<Directory> d3subs = d3.subdirectories();
    List<Directory> d4subs = d4.subdirectories();

    assertTrue(d1subs.contains(d2));
    assertTrue(d1subs.contains(d3));
    assertTrue(d2subs.isEmpty());
    assertFalse(d1subs.contains(d4));
    assertTrue(d3subs.contains(d4));
    assertTrue(d4subs.isEmpty());
}

This typechecks, but when I run the tests, I get the following error:

A java.lang.IllegalArgumentException has been caught, Parameter value [5] was not matching type [models.Directory]
In /test/models/DirectoryTest.java, line 37 :
List<Directory> d1subs = d1.subdirectories();

Can anyone explain what the problem is, and how to fix it?

Answer 1

Shouldn’t this be

return find("select d from Directory d where d.parent.id = ?", this.id).fetch();

or a shortened version of the same should be

return find("parent.id = ?", this.id).fetch();