Mock为测试代码带来混乱和重复
下面的代码使用 EasyMock 测试：EmployeeBO用EmployeeDAO存储新员工信息和更新当前员工信息。
@Before public void setUp() {
mockEmployeeDAO = createMock(EmployeeDAO.class);
employeeBO = new EmployeeBO(mockEmployeeDAO);
employee = new Employee("Alex", "CA", "US");
}
@Test public void shouldAddNewEmployee() {
mockEmployeeDAO.insert(employee);
replay(mockEmployeeDAO);
employeeBO.addNewEmployee(employee);
verify(mockEmployeeDAO);
}
@Test public void shouldUpdateEmployee() {
mockEmployeeDAO.update(employee);
replay(mockEmployeeDAO);
employeeBO.updateEmployee(employee);
verify(mockEmployeeDAO);
}测试方法shouldAddNewEmployee用于验证测试对象（employeeBO ）和Mock（mockEmployeeDAO ）之间交互是否正确。它期望employeeBO调用mockEmployeeDAO中的insert方法，并将接收到的Employee实例传递给该方法。shouldAddNewEmployee方法虽然简单，但其中含有一些没有实际目的的代码，这为我们的测试带来了混乱：
- 重复调用replay，通知EasyMock所有期望的工作已完成。
- 重复调用verify，通知EasyMock所有期望的工作已验证完成。
Mock的使用常常遵循下面的模式：
- 建立Mock和期望
- 执行要测试的代码
- 验证执行结果是否符合期望
这种模式会在测试代码中引入重复，这在测试方法shouldAddNewEmployee()和shouldUpdateEmployee()中很明显。使用 EasyMockTemplate 可以减少代码混乱和重复：
/**
* Understands a template for usage of EasyMock mocks.
* @author Alex Ruiz
*/
public abstract class EasyMockTemplate {
/** Mock objects managed by this template */
private final List<Object> mocks = new ArrayList<Object>();
/**
* Constructor.
* @param mocks the mock objects this template will manage.
* @throws IllegalArgumentException if the list of mock objects is null or empty.
* @throws IllegalArgumentException if the list of mock objects contains a null value.
*/
public EasyMockTemplate(Object... mocks) {
if (mocks == null) throw new IllegalArgumentException("The list of mock objects should not be null");
if (mocks.length == 0) throw new IllegalArgumentException("The list of mock objects should not be empty");
for (Object mock : mocks) {
if (mock == null) throw new IllegalArgumentException("The list of mocks should not include null values");
this.mocks.add(mock);
}
}
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文章来源于领测软件测试网 https://www.ltesting.net/
