Getting MissingMethodInvocationException while testing with servlet and session-CodePudding

I'm trying to test my servlet to see if it calls my DAOService with some passed parameters from the session but running into this problem

The log:

org.mockito.exceptions.misusing.MissingMethodInvocationException: 
when() requires an argument which has to be 'a method call on a mock'.
For example:
    when(mock.getArticles()).thenReturn(articles);
at Servlet.SupplierServletTest.supplierServlet_StandardTest(SupplierServletTest.java:32)

The code

SupplierServlet supplierServlet = new SupplierServlet();
MockHttpServletRequest request = new MockMvcRequestBuilders.get("/SupplierServlet").buildRequest(new MockServletContext());
MockHttpServletResponse response = new MockHttpServletResponse();
MockHttpSession session = new MockHttpSession();

when(request.getSession()).thenReturn(session); //This is the line 32 that the log mentioned, I deleted the session part and the problem was the same for the following lines
when(request.getParameter("Name")).thenReturn("test"); 
when(request.getParameter("Address")).thenReturn("test");
when(request.getParameter("Phone")).thenReturn("1234");

supplierServlet.processRequest(request, response);
supplierDAO = mock(SupplierDAO.class);
verify(supplierDAO).newSupplier(new Supplier("test", "test", "1234"));

Any tip is appreciated

CodePudding user response：

As for initialising MockHttpServletRequest, you should use the Spring provided builder. Since it is a class offered by the Spring framework (and is not a Mockito mock), using Mockito to mock its methods will result in an error.

MockHttpServletResponse response = new MockHttpServletResponse();
MockHttpSession session = new MockHttpSession();
MockHttpServletRequest request = MockMvcRequestBuilders.get("/SupplierServlet")
    .session(session)
    .param("Name", "test")
    .param("Address", "test")
    .param("Phone", "1234")
    .buildRequest(new MockServletContext());

supplierServlet.processRequest(request, response);
supplierDAO = mock(SupplierDAO.class);
verify(supplierDAO).newSupplier(new Supplier("test", "test", "1234"));

Moreover, your supplierDAO mock is useless. After mocking an object, you need to inject it into the code under test. It is usually done by passing the mock as a function parameter. Whereas in your test, you're trying to verify calls on a mock that was never used.