[Demonstration 1]

[Buggy Method]
private void setRegionList() {
    progressDialog.show();
    String urlStr = R.string.php_server_url + "getRegions.php";
    //request for Region list
    JsonObjectRequest request = new JsonObjectRequest(Request.Method.GET, urlStr, null, new Response.Listener<JSONObject>() {

        @Override
        public void onResponse(JSONObject resultSet) {
            // Result handling
            try {
                List<Region> list = new ArrayList<>();
                list.add(new Region());
                //show potential error
                if (resultSet.getBoolean("erreur")) {
                    Toast.makeText(getApplicationContext(), resultSet.getString("message"), Toast.LENGTH_SHORT).show();
                } else {
                    // get all Region from the data Array
                    JSONArray data = resultSet.getJSONArray("donnees");
                    for (int i = 0; i < data.length(); i++) {
                        JSONObject region = data.getJSONObject(i);
                        String codeRegion = region.getString("code_region");
                        String nomRegion = region.getString("libelle_region");
                        list.add(new Region(codeRegion, nomRegion));
                    }
                    // fill the Region Spinner
                    ArrayAdapter<Region> adapter = new ArrayAdapter<>(getApplicationContext(), android.R.layout.simple_spinner_item, list);
                    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
                    regionSpinner.setAdapter(adapter);
                    //Show message
                    Toast.makeText(getApplicationContext(), R.string.choose_region, Toast.LENGTH_SHORT).show();
                }
            } catch (JSONException e) {
                //show potential error
                Toast.makeText(getApplicationContext(), R.string.wrong_data_message, Toast.LENGTH_LONG).show();
            }
            progressDialog.dismiss();
        }
    }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            //show potential error
            progressDialog.dismiss();
            Toast.makeText(getApplicationContext(), R.string.connection_error_message, Toast.LENGTH_LONG).show();
        }
    });
    // Add the request to the queue
    Volley.newRequestQueue(this).add(request);
}

[Buggy Hunk]
String urlStr = R.string.php_server_url + "getRegions.php";

[Patch]
String urlStr = getApplicationContext().getString(R.string.php_server_url) + "getRegions.php";

[Demonstration 2]

[Buggy Method]
public boolean fullHouse() {
    if (this.pair() && this.threeOfAKind()) {
        return true;
    }
    return false;
}

[Buggy Hunk]
if(this.pair()&&this.threeOfAKind()){

[Patch]
if(pair()&&threeOfAKind()){

[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));