private boolean registerProvider()

in src/main/java/org/apache/sling/superimposing/impl/SuperimposingManagerImpl.java [172:227]
43 lines of code
10 McCabe index (conditional complexity)

    private boolean registerProvider(Resource superimposingResource) {
        String superimposePath = superimposingResource.getPath();

        // use JCR API to get properties from superimposing resource to make sure superimposing does not delivery values from source node
        final String sourcePath = getJcrStringProperty(superimposePath, PROP_SUPERIMPOSE_SOURCE_PATH);
        final boolean registerParent = getJcrBooleanProperty(superimposePath, PROP_SUPERIMPOSE_REGISTER_PARENT);
        final boolean overlayable = getJcrBooleanProperty(superimposePath, PROP_SUPERIMPOSE_OVERLAYABLE);

        // check if superimposing definition is valid
        boolean valid = true;
        if (StringUtils.isBlank(sourcePath)) {
            valid = false;
        }
        else {
            // check whether the parent of the node should be registered as superimposing provider
            if (registerParent) {
                superimposePath = ResourceUtil.getParent(superimposePath);
            }
            // target path is not valid if it equals to a parent or child of the superimposing path, or to the superimposing path itself
            if (StringUtils.equals(sourcePath, superimposePath)
                    || StringUtils.startsWith(sourcePath, superimposePath + PATH_SEPARATOR)
                    || StringUtils.startsWith(superimposePath, sourcePath + PATH_SEPARATOR)) {
                valid = false;
            }
        }

        // register valid superimposing
        if (valid) {
            final SuperimposingResourceProviderImpl srp = new SuperimposingResourceProviderImpl(superimposePath, sourcePath, overlayable);
            final SuperimposingResourceProviderImpl oldSrp = superimposingProviders.put(superimposePath, srp);

            // unregister in case there was a provider registered before
            if (!srp.equals(oldSrp)) {
                log.debug("(Re-)registering resource provider {}.", superimposePath);
                if (null != oldSrp) {
                    oldSrp.unregisterService();
                }
                srp.registerService(bundleContext);
                return true;
            } else {
                log.debug("Skipped re-registering resource provider {} because there were no relevant changes.", superimposePath);
            }
        }

        // otherwise remove previous superimposing resource provider if new superimposing definition is not valid
        else {
            final SuperimposingResourceProviderImpl oldSrp = superimposingProviders.remove(superimposePath);
            if (null != oldSrp) {
                log.debug("Unregistering resource provider {}.", superimposePath);
                oldSrp.unregisterService();
            }
            log.warn("Superimposing definition '{}' pointing to '{}' is invalid.", superimposePath, sourcePath);
        }

        return false;
    }