Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Mocking in Java with Mockito

Related Books

Free with a 30 day trial from Scribd

See all
  • Be the first to comment

Mocking in Java with Mockito

  1. 1. A mocking framework for Java Richard Paul -
  2. 2. State vs Interaction testing State testing asserts properties on an object e.g. assertEquals(4, item.getCount()); Interaction testing verifies the interactions between objects. e.g. Did my controller correctly call my service. Mockito provides a framework for interactions testing.
  3. 3. Test Doubles Terminology defined by Gerard Meszaros. See: Test Stub Hand coded object used for testing. Mock object (e.g. EasyMock) Expectations configured before calling the method under test. Test Spy (e.g. Mockito) Verification occurs after the method under test has been called.
  4. 4. Mockito Example Simple MVC example: Item - simple POJO (has a name and ID). ItemController - handles requests from the browser. ItemService - service the ItemController delegates to. ItemNotFoundException Following slides detail testing the ItemController using Mockito. Note: the controller is implemented using a Springframework 2.5 annotation style, with annotations omitted for clarity.
  5. 5. View Item - using when Eclipse then generates the viewItem method signature in
  6. 6. Test Failure Then implement viewItem to pass the test
  7. 7. Delete Item - using verify Eclipse then generates the deleteItem method signature in
  8. 8. Wanted, but not invoked
  9. 9. Exceptional Cases - using thenThrow Allows simple testing of exceptional cases with similar syntax to thenReturn .
  10. 10. Initialising mocks in Mockito Allows access to when, verify etc without the ... Mockito.prefix ...
  11. 11. Default Values Mockito provides default values (null, 0, empty list, etc) for method calls that have not been defined. This allows you to define only the interactions that are relevant to your test. See slides by Szczepan Faber Slides 8-31 Why ignore interactions not directly related to a test case? (slide 29) quot;because aggressive validation makes the tests brittlequot; quot;because I have to fix tests even when the code is not brokenquot; quot;... can increase noisequot; quot;or lead to overspecificationquot;
  12. 12. More features... Verify how many times a method is called. e.g. verify(itemService, never()).deleteItem(3); verify(itemService, atLeastOnce()).deleteItem(3); verify(itemService, times(3)).deleteItem(3); Verify the order calls are made using InOrder Chain subsequent calls to return different values. when(itemService.getItem(3)) .thenReturn(item1) .thenReturn(item2); Argument matchers when(service.get(eq(1), anyFloat()).thenReturn(quot;xquot;); Can mock concrete classes (uses cglib)
  13. 13. Comments, queries, suggestions or theories? Slides + code examples will be up on

    Be the first to comment

    Login to see the comments

  • asantos_2000

    Feb. 5, 2010
  • gordonad

    May. 11, 2010
  • 777rakesh

    Sep. 15, 2011
  • colinkuo

    Nov. 10, 2011
  • samchuang

    Sep. 26, 2012
  • barcel0

    Jan. 23, 2013
  • sandeepmandrumaka

    May. 23, 2013
  • stefanteixeira

    May. 31, 2013
  • stadlerb

    Jul. 12, 2013
  • pkoduganty

    Oct. 6, 2013
  • balladofgale

    Jan. 6, 2014
  • guilhermeis

    Jun. 13, 2014
  • strongback

    Jul. 21, 2015
  • ThangLamHuu

    Sep. 22, 2015
  • miconi

    Mar. 14, 2016
  • niravkk

    Apr. 1, 2017
  • glevinsh

    Oct. 8, 2017
  • ManojPatra5

    Nov. 10, 2017
  • OlgaYaremchuk

    Nov. 27, 2019
  • AbdelhaqZouha

    Oct. 20, 2020


Total views


On Slideshare


From embeds


Number of embeds