public final void addAppKey(final String applicationKey) throws IllegalArgumentException {
        /*if (this.appKeys.contains(applicationKey))
            throw new IllegalArgumentException("App key already exists");*/

        this.appKeys.add(applicationKey);
        saveApplicationKeys();
    }
Adds an application key to the application keys list

@param applicationKey application key to be added in the specified position
mesh/src/main/java/no/nordicsemi/android/mesh/ProvisioningSettings.java