检查是否抛出例外并在抛出例外后继续

Question

我想进行一个从文件中读取一些数据并将数据传递给函数的测试。该功能调用其他方法，其中一些方法引发了一些例外。我对如何查看使用文件中的参数调用该方法是否触发了ioexception的某个地方。我知道提供的代码段将停止执行，因为我使用了断言。如果要检查是否抛出了IOException，以及如果是的，则该如何写入错误消息，而无需停止执行测试？谢谢！

void test() throws IOException {
    Service service = helperFunction();
    File articles = new File("file.txt");
    Scanner scanner = new Scanner(articles);
    while(scanner.hasNextLine()) {
        String line = scanner.nextLine();
        line = line.replaceAll("[^\\d]", " ");
        line = line.trim();
        line = line.replaceAll(" +", " ");
        String[] numberOnTheLine = line.split(" ");

        List<Integer> list = Arrays.stream(numberOnTheLine).map(Integer::valueOf).collect(Collectors.toList());
        Article article = new Article(Long.valueOf(list.get(0)),
                new HashSet<>(List.of(new Version(list.get(1)))));

        List<List<Article>> listOfArticles = Collections.singletonList(List.of(article));
        Assertions.assertThrows(IOException.class,
                () -> service.etlArticles(listOfArticles.stream().flatMap(List::stream).collect(Collectors.toList())));
    }
}

Answer 1

简单的;尝试/捕获的声明将照顾好它。

替换此：

  service.etlartsicles（listofarticles.stream（）。flatmap（list :: stream）.collect（collectors.tolist（）））;
 

使用：

try {
 
 service.etlArticles(listOfArticles.stream().flatMap(List::stream).collect(Collectors.toList())));
} catch (IOException e) {
  // Code jumps to here if an IOException occurs during the execution of anything in the try block
}

您可以自由进行一些记录，然后只需assert.fail，如果需要。

essertthrows非常简单，只有这样做：

  try {
    runThatCode();
  } catch (Throwable e) {
    if (e instanceof TypeThatShouldBeThrown) {
      // Great, that means the code is working as designed, so, just...
      return;
    }
    // If we get here, an exception was thrown, but it wasn't the right type.
    // Let's just throw it, the test framework will register it as a fail.
    throw e;
  }

  // If we get here, the exception was NOT thrown, and that's bad, so..
  Assert.fail("Expected exception " + expected + " but didn't see it.");
}

现在您知道它的工作原理，可以自己编写，从而添加，更改或日志或在此过程中在正确的位置进行的任何操作。但是，鉴于您知道这是ioException，而不是instanceof检查您可以只是catch（ioexception e），更简单。