@Override
    public void applyExternalChanges(User existingObject,
            APIUser object) throws GuacamoleException {

        // Do not update the user password if no password was provided
        if (object.getPassword() != null)
            existingObject.setPassword(object.getPassword());
        
        // Update disabled status
        existingObject.setDisabled(object.isDisabled());

        // Update user attributes
        existingObject.setAttributes(object.getAttributes());

    }
Translator which converts between User objects and APIUser objects.
guacamole/src/main/java/org/apache/guacamole/rest/user/UserObjectTranslator.java