Where in the Callable Statement stays the registerParameterOut?

Question

I'm trying to make a integration test for a method that a call a procedure, the values are coming, but I just want to know where in the callableStatement variable is the value of the registerParameterOut, because I want to mock, after the return, a value in one of the index, to force a success test, I don't know a way to do it, I tried things like this:

TestMethod

@Test
public void returnSucess() {
    ExampleClass example = ExampleClass.createExample();
    ArrayList<String> mock = new ArrayList<>();

    mock.add("14");
    mock.add("1234");
    mock.add("331");
    mock.add("000");
    mock.add("Test");
    mock.add("Test");
    mock.add(null);


    assertDoesNotThrow(() -> {
        when(mapper.toCallProcedure(example)).thenReturn(mock);
        given(callableStatement.getObject(13)).willReturn("00"); //Tried with when too, and using getString(13)... But it couldn't change the value
        adapterOut.Method(example);
    });
}

The way that I call the proc

stmt = conn.prepareCall(Query);
        stmt.setString(1, value1);
        stmt.setString(2, value2);
        stmt.setString(3, value3);
        stmt.setString(4, value4);
        stmt.setString(5, value5);
        stmt.setString(6, value6);
        stmt.setString(7, value7);

        stmt.registerOutParameter(8, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(9, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(10, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(11, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(12, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(13, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(14, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(15, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(16, java.sql.Types.VARCHAR);
        stmt.registerOutParameter(17, java.sql.Types.VARCHAR);

        try {
            stmt.executeQuery();

I tried to put a breakpoint after executeQuery, and search for the values of registerOutParameter, but I couldn't find it, the only way to take the values is using getObject(index) or getString(index). (When I try to use stmt.getResultSet() the return is null and trying to use something that I saw here in stackOverflow ResultSet resultSet = (ResultSet) stmt.getObject(index) it's throwing a exception that can't convert java....sql to ResultSet or something like that).

There's a way to get the change the value in real time of execution or mocking in the integration/unit test?

Thanks for advice!