如何使用mockito-inline模拟抛出IOException的构造函数？

Question

如何模拟构造函数行：

Workbook templateWorkBook = null;
try {
  templateWorkBook = new XSSFWorkbook(templateWithoutEvents);
} catch (IOException ex){
  log.error("Error creating workbook from file");
}

我正在尝试类似的方法，但不起作用。

try (
                MockedConstruction<XSSFWorkbook> mocked = Mockito.mockConstructionWithAnswer(XSSFWorkbook.class, invocation -> null)
                ) {
            doReturn("2021-09-30").when(stpConfigurationMock).getStartDate();
            **when(new XSSFWorkbook()).thenThrow(IOException.class);**
            Workbook workBook = fileService.generateReport(listItem, startDate, endDate);
        }

运行测试时出现异常：

org.mockito.exceptions.misusing.MissingMethodInvocationException: 
when() requires an argument which has to be 'a method call on a mock'.
For example:
    when(mock.getArticles()).thenReturn(articles);

Answer 1

我试图自己找到这个问题的解决方案，并且使用这个解决方案适用于我的情况：

try (MockedConstruction<XSSFWorkbook> mocked = 
Mockito.mockConstructionWithAnswer(XSSFWorkbook.class, invocation -> {
    throw new IOException();
})) {
    Workbook workBook = fileService.generateReport(listItem, startDate, endDate);
}

构造函数本身并没有被MockedConstruction模拟，而是被拦截。这解释了您遇到的错误