Prevent execution of JUnit tests or forcing a special execution order of JUnit tests?

Question

Usually every JUnit test should be encapsulated, but I need to test if an encrypted file stored by EncryptorTest can be decrypted by another Java VM instance in DecryptorTest. You can manage this by running 2 different JUnit test classes (not JUnit tests itself!). The only problem is that I have to guarantee that EncryptorTest runs before DecryptorTest (because the first one saves the file with the encrypted string). How can I do that? I thought about using a TestSuite:

@RunWith(Suite.class)
@SuiteClasses({EncryptorTest.class, DecryptorTest.class})
public class EncrypterDecrypterTestSuite
{
}

But on server every JUnit test will run by itself too, so EncryptorTest and DecryptorTest can get mixed up. How can I prevent this?

Answer 1

JUnit doesn't support the ordering of tests, you might want to use TestNG for this (here is the relevant doc).

Answer 2

Typically JUnit is used for unit testing, so there shouldn't be dependencies between test cases. You could use the @Before annotation to setup the encryption before the decryption or better yet, load an encryption file from the filesystem or feed it in programmatically.

Answer 3

I solved it in a different way, now. I omit the EncrypterTest and just encrypted the text in a file by myself and let the DecrypterTest read this file all the time. So I don't have to care about running it in different VMs.