Welcome to Software Development on Codidact!

Will you help us build our independent community of developers helping developers? We're small and trying to grow. We welcome questions about all aspects of software development, from design to code to QA and more. Got questions? Got answers? Got code you'd like someone to review? Please join us.

Post History

37%

+1 −3

Q&A Mocking methods with arguments

Let's say I have this class I want to mock class A { public void add(T arg) { B b = A.getB(); U val = somefunc(arg); V ret = b.add(val); } } I have a spy o...

3 answers · posted 2y ago by klutt‭ · last activity 2y ago by klutt‭

Question java mocking junit mockito

#3: Post edited by

Alexei‭ · 2022-02-25T15:50:12Z (about 2 years ago)
added relevant tag

Copy Link

Raw

Markdown

java junit mockito

java mocking junit mockito

#2: Post edited by

klutt‭ · 2022-02-25T14:47:28Z (about 2 years ago)

Copy Link

Raw

Markdown

Let's say I have this class I want to mock
class A {
~~protected B b;~~
public void add(T arg) {
U val = somefunc(arg);
V ret = b.add(val);
}
}
I have a spy on A and a mock on B, but when A::foo calls B::bar, I want it to be mocked. But I want some stuff to be done inside it. Something like this:
class BMock {
List<U> ulist = new ArrayList<>();
R add(U u) {
if(ulist.contains(u)) throw exception;
}
return new R(x);
}
But I'm having a bit of a problem how to do this. I'm looking for something on this form:
A a = spy(A.class);
B b = mock(B.class);
a.b = b;
BMock bm = new BMock();
doAnswer(bm.add(arg)).when(b).add(any());
^ |
| |
------------------
What I want to do is to send the any argument over to bm.add
In the real code, B::add will contact a remote server to add an item. If it gets called twice with the same item, the server will return an error. A::add will analyze this return code and act accordingly. And this is what I'm trying to simulate. How should I do it?

Let's say I have this class I want to mock
class A {
public void add(T arg) {
B b = A.getB();
U val = somefunc(arg);
V ret = b.add(val);
}
}
I have a spy on A and a mock on B, but when A::foo calls B::bar, I want it to be mocked. But I want some stuff to be done inside it. Something like this:
class BMock {
List<U> ulist = new ArrayList<>();
R add(U u) {
if(ulist.contains(u)) throw exception;
}
return new R(x);
}
But I'm having a bit of a problem how to do this. I'm looking for something on this form:
A a = spy(A.class);
B b = mock(B.class);
a.b = b;
BMock bm = new BMock();
doAnswer(bm.add(arg)).when(b).add(any());
^ |
| |
------------------
What I want to do is to send the any argument over to bm.add
In the real code, B::add will contact a remote server to add an item. If it gets called twice with the same item, the server will return an error. A::add will analyze this return code and act accordingly. And this is what I'm trying to simulate. How should I do it?
### EDIT
I got some suggestions in comment section. But I might add that I cannot change B because it's an external library, and the class B both misses default constructor and is final.

#1: Initial revision by

klutt‭ · 2022-02-25T11:35:04Z (about 2 years ago)

Copy Link

Raw

Markdown

Mocking methods with arguments

Let's say I have this class I want to mock

    class A {
        protected B b;

        public void add(T arg) {
            U val = somefunc(arg);
            V ret = b.add(val);
        }
    }

I have a spy on A and a mock on B, but when A::foo calls B::bar, I want it to be mocked. But I want some stuff to be done inside it. Something like this:

    class BMock {
        List<U> ulist = new ArrayList<>();

        R add(U u) {
            if(ulist.contains(u)) throw exception;
        }

        return new R(x);
    }

But I'm having a bit of a problem how to do this. I'm looking for something on this form:

    A a = spy(A.class);
    B b = mock(B.class);
    a.b = b;
    BMock bm = new BMock();
    doAnswer(bm.add(arg)).when(b).add(any());
                     ^                  |
                     |                  |
                      ------------------

What I want to do is to send the any argument over to bm.add




In the real code, B::add will contact a remote server to add an item. If it gets called twice with the same item, the server will return an error. A::add will analyze this return code and act accordingly. And this is what I'm trying to simulate. How should I do it?

java junit mockito

Communities

Post History