    @Test
    public void estimatedSizeOfWithoutLiteral() throws Exception {

        // Arrange
        Statement statement = VALUE_FACTORY.createStatement(
                VALUE_FACTORY.createBNode("http://a"),
                VALUE_FACTORY.createURI("http://b"),
                VALUE_FACTORY.createURI("http://c"),
                VALUE_FACTORY.createURI("http://d"));

        // Act
        long size = StatementSizeEstimator.estimatedSizeOf(statement);

        // Assert
        long stringsSize = 4 * StringSizeEstimator.estimatedSizeOf("http://a");
        long minOverhead = 5 * 8 + 9 * 4 + 4 * 8; // objects + object references + int fields
        long maxOverhead = 5 * 16 + 9 * 8 + 4 * 8;
        assertTrue(size <= maxOverhead + stringsSize);
        assertTrue(size >= minOverhead + stringsSize);
    }