List<ComplexParam> params = new ArrayList<>();
params.add(new ComplexParam("prop1_1", 33));
params.add(new ComplexParam("prop1_2", 44));
List<ComplexParam> returnParams = obj.echoListRegister(params);
ComplexParam value1 = returnParams.get(0);
ComplexParam value2 = returnParams.get(1);
assertEquals(value1.getProp1(), "prop1_1");