[Demonstration 1]

[Buggy Method]
@Override
public Void answer(InvocationOnMock invocation) throws Throwable {
    ILoggingEvent event = invocation.getArgumentAt(0, ILoggingEvent.class);
    if (event != null && filter.apply(event)) {
        events.add(event);
    }
    LOG.trace("level=" + event.getLevel() + "; event=" + event + "; msg=" + event.getFormattedMessage());
    return null;
}

[Buggy Hunk]
ILoggingEvent event = invocation.getArgumentAt(0, ILoggingEvent.class);

[Patch]
ILoggingEvent event = invocation.getArgument(0);

[Demonstration 2]

[Buggy Method]
@Override
public void run() {
    int endpoint = 0;
    while (!stop) {
        if (endpoint == 0) {
            host = msg.getClientPrivateIP();
            port = msg.getClientPrivatePort();
            endpoint++;
        } else {
            host = msg.getClientPublicIP();
            port = msg.getClientPublicPort();
            endpoint = 0;
        }
        LoopHolePunchMessage punchMsg = beanService.getBean(LoopHolePunchMessage.class);
        punchMsg.setTo(msg.getFromId());
        punchMsg.setFrom(loopHoleService.getClientID());
        punchMsg.setName(loopHoleService.getName());
        loopHoleService.addInWaitFromAckQueu(msg.getFromId(), this);
        loopHoleService.send(msg, host, port);
        isWaitingForAck = true;
        try {
            Thread.sleep(500);
        } catch (InterruptedException ex) {
            PieLogger.error(this.getClass(), "Error while waiting for ACK", ex);
        }
        isWaitingForAck = false;
        loopHoleService.removeTaskFromAckWaitQueue(msg.getFromId());
    }
}

[Buggy Hunk]
loopHoleService.send(msg, host, port);

[Patch]
loopHoleService.send(punchMsg, host, port);

[Demonstration 3]

[Buggy Method]
public static Result service(String ownerName, String projectName, String service, boolean isAdvertise) throws IOException, UnsupportedOperationException, ServletException {
    if (!isSupportedService(service)) {
        return forbidden(String.format("Unsupported service: '%s'", service));
    }
    Project project = Project.findByOwnerAndProjectName(ownerName, projectName);
    if (project == null) {
        return notFound();
    }
    models.User user = UserApp.currentUser();
    if (!isAllowed(project, service)) {
        if (user.isAnonymous()) {
            return BasicAuthAction.unauthorized(response());
        } else {
            // If you want the Git client showing your custom message to
            // the user, the Content-Type should be exact "text/plain"
            // without any parameter. For more details, see the code at
            // https://github.com/git/git/commit/426e70d4a11ce3b4f70636d57c6a0ab16ae08a00#diff-eea0ad565ec5903a11b6023755d491cfR154
            response().setHeader("Content-Type", "text/plain");
            return forbidden(String.format("'%s' has no permission to '%s/%s'.", user.name, ownerName, projectName));
        }
    }
    if (isAdvertise) {
        return ok(RepositoryService.gitAdvertise(project, service, response()));
    } else {
        if (request().body().isMaxSizeExceeded()) {
            return status(REQUEST_ENTITY_TOO_LARGE);
        } else {
            user.visits(project);
            return ok(RepositoryService.gitRpc(project, service, request(), response()));
        }
    }
}

[Buggy Hunk]
user.name, ownerName, projectName));

[Patch]
user.loginId, ownerName, projectName));