@Test
public void evaluateConstant(){

	Constant stringThree = new Constant("3");
	stringThree.setDataType(DataType.STRING);
	assertEquals("3", evaluate(stringThree, null));
	Constant integerThree = new Constant("3");
	integerThree.setDataType(DataType.INTEGER);
	assertEquals(3, evaluate(integerThree, null));
	Constant floatThree = new Constant("3");
	floatThree.setDataType(DataType.FLOAT);
	assertEquals(3f, evaluate(floatThree, null));
}