FilterFilter implements Predicate<ChildVisitor> { @Override public boolean apply(ChildVisitor input) { Preconditions.checkNotNull(input); if (input instanceof FieldEquality) return true; else return false; }  @Override boolean apply(ChildVisitor input);  }
@Test(expected = NullPointerException.class) public void testNull() { FilterFilter filter = new FilterFilter(); filter.apply(null); }
@Test public void testOrFalse() { FilterFilter filter = new FilterFilter(); assertFalse(filter.apply(new OrOperator())); }
@Test public void testConjunctionPositive() { FilterFilter filter = new FilterFilter(); assertTrue(filter.apply(new FieldEquality(new Field("field"),new Literal("literal")))); }