snippets/ecm-integrations/invoice-box/src/main/java/org/camunda/bpm/example/box/BoxHelper.java
public static BoxDeveloperEditionAPIConnection userClient(String userId) {
        if (userId == null) { //   session data has expired
            return null;
        }
        System.out.format("userClient called with userId %s \n\n", userId);
        try {
            BoxDeveloperEditionAPIConnection userClient = BoxDeveloperEditionAPIConnection.getAppUserConnection(
                    userId, CLIENT_ID, CLIENT_SECRET, jwtEncryptionPreferences, accessTokenCache);
            return userClient;
        } catch (BoxAPIException apiException) {
            apiException.printStackTrace();
            throw apiException;
        }
    }
public static BoxDeveloperEditionAPIConnection userClient(String userId) {
        if (userId == null) { //   session data has expired
            return null;
        }
        System.out.format("userClient called with userId %s \n\n", userId);
        try {
            BoxDeveloperEditionAPIConnection userClient = BoxDeveloperEditionAPIConnection.getAppUserConnection(
                    userId, CLIENT_ID, CLIENT_SECRET, jwtEncryptionPreferences, accessTokenCache);
            return userClient;
        } catch (BoxAPIException apiException) {
            apiException.printStackTrace();
            throw apiException;
        }
    }
Get a BoxDeveloperEditionAPIConnection that can be used by an App user to access Box.

@param userId The UserId of a valid Box App User
@return BoxDeveloperEditionAPIConnection new Box Developer Edition connection with App User token