Java学习Day1

Test Driven Development

hard to test software write test first

manual test

• not repeatable
• not structured
• not standardised reporting

  unit testing

• a method/a database query/stored proc/a dynamic web page
• automated,self-validating,consistent/repeatable,independent,readable,fast

  AAA Arrange Act Assert : Given When Then

  void testConnotOverDraw(){
  //Arrange
  BankAccount ac = new BankAccount(5000);
  //Act
  Ac.withdraw(3000);
  //Assert
  Assertequals(2000,ac.get_balance());
  }
  

  Unit Testing with JUnit

  one-off setup/teardown assertThat()

  Hamcrest matchers

• more expressive
• clearer
• no need for optional String message

  is(),equalTo()
  not()
  instanceOf()
  nullValue(),notNullValue()
  sameInstance()
  lessThanOrEqualTo()
  allOf(),anyOf()
  endsWith()
  closeTo()
  hasItem()
  

  Define a Custom Macher

  todO:

  grouping tests together

  @RunWith(value=Suite.class)

  Test with Mock

  NumberGenerator mocGenerator = createMock(NumberGenerator.class);
  for(int i=1;i<7;i++){
  expect(mocGenerator.generate(anyInt)).andReturn(i);
  }
  replay(mockGenerate);
  Lottery lotto = new Lottery(mockGenerate);
  Set<Integer> numbers = lotto.generateRandomSet();
  assertThat(lotto.formatNumbers(numbers),is("1-2-3-4-5-6"))
  verify(mockGenerate);
  

  EasyMock: Introduction

• Create required mock objects,e.g. via createMock()
• Create an instance of the CUT,replacing dependencies on real collaborators with mocks
• set expections on mock(s)
• call replay(),which indicates expectation-setting has finished
• invoke a method on CUT, to verify if the mock get the calls we expected
• Optionally, make assertions(as before)

Note: To use EasyMock, you must ensure easymock.jar is on the classpath, and that you import the org.easymock.EasyMock class. The EasyMock class contains a whole bunch of important static methods, e.g. createMock(), expect(), replay(), and verify()

There are several ways to create a mock object in EasyMock

• createStrickMock(): 1. no unexpected method calls 2. the order of the calls must be as per expectations.
• createMock: 1. no unexpected calls 2.
• createNiceMock:

  EasyMock: Setting expections

• for a void method, use expectLastCall()
• if you want to specify the cardinality, use: times(int count)

  EasyMock: Replay and verify

• replay(mockRequest,mockResponse ) this indicates you’ve finished setting expections,and are ready to check if the expected method invocations are actually made
• verify: this verifies that the tested object did perform all the method calls that were expected of it.

  Variations(变种)

• Classes can be mocked : add cglib-nodep and objenesis jars to the classpath
• make your test class extend EasyMockSupport : replayAll() verifyAll()