[Demonstration 1]

[Buggy Method]
public void merge(String formName, Item item, Record record) {
    Record itemLookup = record;
    Set<String> addedMetadata = new HashSet<String>();
    for (String field : itemLookup.getFields()) {
        String metadata = getMetadata(formName, itemLookup, field);
        if (StringUtils.isBlank(metadata)) {
            continue;
        }
        if (item.getMetadata(metadata).length() == 0 || addedMetadata.contains(metadata)) {
            addedMetadata.add(metadata);
            String[] md = splitMetadata(metadata);
            if (isValidMetadata(formName, md)) {
                // if in extra metadata or in the spefific form
                List<Value> values = itemLookup.getValues(field);
                if (values != null && values.size() > 0) {
                    if (isRepeatableMetadata(formName, md)) {
                        // if metadata is repeatable in form
                        for (Value value : values) {
                            String[] splitValue = splitValue(value.getAsString());
                            if (splitValue[3] != null) {
                                item.addMetadata(md[0], md[1], md[2], md[3], splitValue[0], splitValue[1], Integer.parseInt(splitValue[2]));
                            } else {
                                item.addMetadata(md[0], md[1], md[2], md[3], value.getAsString());
                            }
                        }
                    } else {
                        String value = values.iterator().next().getAsString();
                        String[] splitValue = splitValue(value);
                        if (splitValue[3] != null) {
                            item.addMetadata(md[0], md[1], md[2], md[3], splitValue[0], splitValue[1], Integer.parseInt(splitValue[2]));
                        } else {
                            item.addMetadata(md[0], md[1], md[2], md[3], value);
                        }
                    }
                }
            }
        }
    }
    try {
        item.update();
    } catch (SQLException e) {
        log.error(e.getMessage(), e);
    } catch (AuthorizeException e) {
        log.error(e.getMessage(), e);
    }
}

[Buggy Hunk]
if (item.getMetadata(metadata).length() == 0

[Patch]
if (item.getMetadataByMetadataString(metadata).length == 0

[Demonstration 2]

[Buggy Method]
private static byte[][] split(byte[] bytes) {
    byte[][] split = new byte[2][16];
    System.arraycopy(bytes, 0, split[0], 0, 16);
    System.arraycopy(bytes, 16, split[1], 0, 16);
    return split;
}

[Buggy Hunk]
private static byte[][] split(byte[] bytes) {

[Patch]
static byte[][] split(byte[] bytes) {

[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));