public void testNullFilter() throws IllegalFilterException { testExp1 = new AttributeExpressionImpl(testSchema, "testDouble"); testExp2 = new AttributeExpressionImpl(testSchema, "testDouble"); testExp3 = new AttributeExpressionImpl(testSchema, "testBoolean"); NullFilterImpl nullFilter1 = new NullFilterImpl(); NullFilterImpl nullFilter2 = new NullFilterImpl(); nullFilter1.setExpression(testExp1); nullFilter2.setExpression(testExp2); assertTrue(nullFilter1.equals(nullFilter2)); nullFilter1.setExpression(testExp3); assertTrue(!nullFilter1.equals(nullFilter2)); assertTrue(!nullFilter1.equals(new BetweenFilterImpl())); }