java - 在 Java 中测试 try-catch block

Question

是否有任何可行的方法来测试哪些Exception 被下面的 Java 方法中的 catch block 捕获，而不更改其当前实现。

public String methodToTest(String text) {
    try
    {
        if (text.contains("something")) {
            throw new CustomException();
        }

        final MyObj myObj = new MyObj(text); //this can throw a MyObjException

        return text;

    } catch (CustomException e) {
        return "An exception has been thrown";
    } catch (MyObjException e) {
        return "An exception has been thrown";
    } catch (Exception e) {
        return "An exception has been thrown";
    }
}

Answer 1

你不应该测试方法的实现，你应该测试你对方法的期望。以下是您提供的方法的一些示例:

• 您希望包含"something" 的text 收到"An exception has been throwed":

测试:

String result = obj.methodToTest("my_something_string");
assertEquals("An exception has been thrown", result);

• 您希望 null 的 text 接收到 “已抛出异常”:

测试:

String result = obj.methodToTest(null);
assertEquals("An exception has been thrown", result);

• 您希望对于 MyObj 无效的 text 收到 “已抛出异常”

测试:

String result = obj.methodToTest("string_not_valid_for_my_obj");
assertEquals("An exception has been thrown", result);

以同样的方式测试其他预期场景。不要测试实现。