[绝对原创] Use Unitils To Simplify Mock Test

[绝对原创] Use Unitils To Simplify Mock Test

Currently, the major approach for java unit test are built on two major components –

• Junit – The unit test framework
• EasyMock and EasyMock Extension – Which are used to build mock test

What’s problem on Mock Test? It costs a lot time on preparation

Mock test is a very good way to test unit of codes. I still prefer mock test as the major approach of unit test. However, mock test has its own problem.

The major steps on Mock Test is –

1. Assume we are going to test “Output ServiceA.MethodA(Input input)”, firstly, get an instance of ServiceA
2. Create an Input for methodA, which generally need new an object and invoke many setter methods to set the values
3. If this method will call ServiceB.MethodB, we need create a mock object for ServiceB, and create an ArugmentMather for methodB to match the arguments, and create a return object for methodB
4. Then we invoke ServiceA.MethodA and internally ServiceA.MethodA will invoke ServiceB.MethodB, and finally, we get the Output object
5. At the last step, we will assert the Output object.

In order to test ServiceA.MethodA, we did lots of things, and most of things are very time-consuming activities, such as

• creating Input object,
• creating Mock service,
• creating ArgumentMacher for mock method, and
• creating return object for mock method
• And assert Output object

What’s my expectation?

• creating Input object – Can it be created automatically?
• creating Mock service – Can it be created automatically?
• creating ArgumentMacher for mock method, and – Can we NOT need create a new class for it?
• creating return object for mock method – Can it be created automatically?
• And assert Output object – Instead of equals() method, can we compare two object by values?

How can Unitils help us?

Unitils is an open source library aimed at making unit testing easy and maintainable. Unitils builds further on existing libraries like dbunit and integrates with JUnit and TestNG .

Unitils provides general asserion utilities, support for database testing, support for testing with mock objects and offers integration with Spring , Hibernate and the Java Persistence API (JPA).

• General testing utilities
  Equality assertion through reflection, with different options like ignoring Java default/null values and ignoring order of collections
• EasyMock integration support
  • Simplify EasyMock mock object creation
  • Simplify mock object injection
  • EasyMock argument matching using reflection equality

Back to our problem –

• Can we initialize a Input or Mock Method Returned Object automatically? In other words, creating an instance of a specific class, and fill all attributes by random values. Unfortunately, Unitils doesn’t have direct support on it. But i’ve created a simple util to initialize an bean based on Unitils.

1  // for BeanInitializer.initializeSimpleBean,  it is an simple tool to initialize a bean by random values. I didn't find a good tool for it, so, i write a simple one.
2  LogStatisticRawDataInput input  =  (LogStatisticRawDataInput) BeanInitializer.initializeSimpleBean(LogStatisticRawDataInput. class );

• Can a mock object be created automatically? Yes, Unitils provides an annotation ”@ReguarMock” to support it
   1  public   class  SearchStatisticServiceImplTest  extends  com.starcite.commonsearch.test.Test {
   2 
   3      
   4 
   5      @RegularMock
   6 
   7       private  StatisticAccess mockAccess;  // just it
   8 
   9      
  10 
  11       private  SearchStatisticService statisticService;
  12 
  13      
  14 
  15      @Before
  16 
  17       public   void  setUp() {
  18 
  19      statisticService  =   new  SearchStatisticServiceImpl();
  20 
  21      ((SearchStatisticServiceImpl)statisticService).setStatisticAccess(mockAccess);
  22 
  23      }
  24 
  25      
  26 
  27      }
• Can we compare the expected object and the real object by contents? Of course, no need write the equals by yourself. Yes, Unitils provides “Equality assertion through reflection, with different options like ignoring Java default/null values and ignoring order of collections”
  1      Map < String, Integer >  expectedKeywordFreqMap  =   new  HashMap < String, Integer > ();
  2 
  3      Map < String, Integer >  keywordFreqMap  =  output.getKeywordFreqMap();
  4      ReflectionAssert.assertReflectionEquals(expectedKeywordFreqMap, keywordFreqMap);  // that's it
• Can we create AugmentMatcher easier? Yes, Unitils provides “EasyMock argument matching using reflection equality”.
   1  // parameter matcher
   2 
   3      StatRawDataImpl rawData  =   new  StatRawDataImpl();
   4 
   5      rawData.setKeyword(input.getKeyword());
   6 
   7      rawData.setLocation(input.getLocation());
   8 
   9      rawData.setAccountID(input.getUserID());
  10 
  11      rawData.setCreatedDate( new  Date());
  12 
  13      rawData.setSiteID(input.getSiteID());
  14 
  15      rawData.setUniqueID(input.getSearchID());
  16 
  17 
  18      List < statsearchrank >  searchRankList  =   new  ArrayList </ statsearchrank >< statsearchrank > (); 
  19 
  20       for  ( int  i  =   0 ; i  & lt; SEARCH_RESULT_SIZE; i ++ ) {
  21 
  22             Long externalVendorID  =  searchResults.get(i);
  23 
  24             StatSearchRank rank  =   new  StatSearchRankImpl();
  25 
  26             rank.setRank((input.getPageNum()  -   1 )  *   // current page number
  27 
  28                                (input.getKeywordLocationPreferredSize()  +  input.getPageSize())  // total page size
  29 
  30                                                        +  i  +   1 );
  31 
  32              rank.setExternalVendorID(externalVendorID);
  33 
  34              searchRankList.add(rank);
  35 
  36      }
  37 
  38      mockAccess.logStatisticRawData(
  39 
  40                  EasyMockUnitils.refEq(rawData, ReflectionComparatorMode.LENIENT_DATES),  // that's it, no need argument matcher
  41 
  42                  EasyMockUnitils.refEq(searchRankList));
  43 
  44      EasyMock.expectLastCall().once();
  45 
  46      EasyMockUnitils.replay();
  47
  

Overall, Unitils  is a pretty good tool to simplify unit test codes. Here  we only mentioned Mock test, actually, Unitils can also simplify DB test/Spring Test etc. We will explore these futures later.