[Demonstration 1]

[Buggy Method]
public void renameFile(AbstractFile file, String name) {
    file.setModDate(new Date());
    log.debug(String.format("file rename from %s to %s ", file.getName(), name));
    MessageService.renameFile(file, name);
    file.setName(name);
    if (file instanceof CryptFile) {
        CryptFile cryptFile = (CryptFile) file;
        String clientId = ContainerPreferences.getInstance().getClientId();
        cryptFile.getVector().increaseModification(clientId);
        if (changeEvents != null && cryptFile.getLength() > 0)
            changeEvents.changeFile(cryptFile);
    } else {
        if (changeEvents != null)
            changeEvents.changeFolder((Folder) file);
    }
    metaData.updateFile(file);
}

[Buggy Hunk]
if(changeEvents != null && cryptFile.getLength() > 0)

[Patch]
if(changeEvents != null)

[Demonstration 2]

[Buggy Method]
public List<Answer> getAnswers() {
    return answers;
}

[Buggy Hunk]
public List<Answer> getAnswers() {

[Patch]
public List<AnswerDetailResult> getAnswers() {

[Demonstration 3]

[Buggy Method]
@Test
public void echoTest() throws Exception {
    System.out.println("echoTest");
    ArrayList<Thread> threads = new ArrayList<Thread>();
    for (int i = 0; i < 10; i++) {
        final int f = i;
        Thread t = new Thread(new Runnable() {

            @Override
            public void run() {
                try {
                    client = StatusClientFactory.getClient(LouieConnectionFactory.getLocalConnection(Identity.createJUnitIdentity()));
                    String result = client.echoTest(Integer.toString(f), 5000);
                    assertNotNull(result);
                    System.out.println(result);
                } catch (Exception ex) {
                    Logger.getLogger(InfoClientTest.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        });
        threads.add(t);
        t.start();
    }
    for (Thread t : threads) {
        while (t.isAlive()) {
            Thread.sleep(10);
        }
        System.out.println("Thread finished");
    }
}

[Buggy Hunk]
ArrayList<Thread> threads = new ArrayList<Thread>();

[Patch]
ArrayList<Thread> threads = new ArrayList<>();