在JUnit测试中强制执行JAXBException

Question

I'm trying to make a JUnit exception test for an unmarshalling method.

This is my unmarshalling method (note: I am returning a String because of normal testing unmarshalling testing with expected string).

public String UnMarshalling(String FILE)
{
    ArrayList<Player> playerList = new ArrayList<Player>();
    try {
        JAXBContext context = JAXBContext.newInstance(Match.class);
        Unmarshaller um = context.createUnmarshaller();
        Match Match2 = (Match) um.unmarshal(new InputStreamReader(new FileInputStream(FILE), StandardCharsets.UTF_8));
        playerList = Match2.playerList;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (JAXBException e) {
        e.printStackTrace();
    }

    return playerList.toString();
}

Here are the tests for this method.

@Test
public void unMarshallingTest() {
    assertTrue(marshalling.UnMarshalling(matchxml).contains("Petras"));
}

@Test(expected=JAXBException.class)
public void marshallingTestException()
{
        marshalling.UnMarshalling(matchbrokenxml);    
}

What I'm trying to achieve is sending broken xml so for example with a wrong version of xml and getting JAXBException .

So far I have scouted internet for an example but found nothing. Any suggestions on how to achieve this?

Answer 1

You are catching and swallowing the exception ie UnMarshalling() never throws a JAXBException (or any subclass of that).

This will work:

public String UnMarshalling(String FILE) throws JAXBException {
    ArrayList<Player> playerList = new ArrayList<Player>();
    try {
        JAXBContext context = JAXBContext.newInstance(Match.class);
        Unmarshaller um = context.createUnmarshaller();
        Match Match2 = (Match) um.unmarshal(new InputStreamReader(new FileInputStream(FILE), StandardCharsets.UTF_8));
        playerList = Match2.playerList;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } 

    return playerList.toString();
}


@Test(expected=UnmarshalException.class)
public void marshallingTestException() {

    marshalling.UnMarshalling(matchbrokenxml);

}

The main change here is the removal of the catch clause for JAXBException and adding throws JAXBException to the method declaration.

Your test strongly suggests that JAXBException is part of the public API for this method, in which case declaring the method to throw JAXBEception makes sense. On the other hand if you really do not want or need JAXBException in the method signature then your test case is either redundant or is addressing the wrong exception type.