How to test methods inner logic where class member is calling another method

Question

I would like to test a agentAgentInfo method as well need to test wsProxy.findAgentInfo method. How can I test it with PowerMockito/Mockito?

    private WSProxy wsProxy = new WSProxy();
    public String getAgentInfo(String loginId) {
        String agentInfo = null;
        try {
           agentInfo = wsProxy.findAgentInfo(loginId);
        } catch (RemoteException e) {
           e.printStackTrace();
        }
        return agentInfo;
    }

Answer 1

Your problem is that you created hard to test code.

There are two options here:

1. You use PowerMock/PowerMockito in order to allow you to inject a mocked WSProxy object at this call: wsProxy = new WSProxy(); That mocked object should then expect a call to findAgentInfo().
2. You change your design to use dependency injection. In other words: instead of your class directly calling new, you use some other mean to acquire such a WSProxy object (for example by receiving one through a constructor).

I usually recommend option 2; and you get there by learning how to create testable code (for example by watching these videos). Yes, PowerMock works for such problems; but the problem is that PowerMock simply doesn't come for free - I have spent hours and hours debugging "issues" with PowerMock; to always figure that the breakage had nothing to do with our production code. So, as tempting as it is; not using PowerMock saves me a lot of time; that I can use to come up with better designs.