SimpleSources implements Sources { @Override public Nulls nulls() throws NullfreeException { final List<Null> nulls = new ArrayList<>(); for (SourceFile file : files.execute()) { nulls.addAll(file.nulls().asList()); } return new SimpleNulls(nulls); } SimpleSources(
        final File folder,
        final SourceFileFactory sourceFactory
    );  SimpleSources(
        final List<SourceFile> files
    );  SimpleSources(final Function0<List<SourceFile>, NullfreeException> files); @Override Nulls nulls();  }
@Test public void findNullsInCurrentProject() throws NullfreeException { Assert.assertThat( new SimpleSources(new File("./src/"), new JavaSourceFileFactory()).nulls().asList().size(), IsEqual.equalTo(0) ); }