private static void createNode(NodeList.Builder nodeBuilder, LinkDataMap linkDataMap) {
        for (LinkData linkData : linkDataMap.getLinkDataList()) {
            final Application fromApplication = linkData.getFromApplication();
            final Application toApplication = linkData.getToApplication();

            // FROM is either a CLIENT or a node
            // cannot be RPC. Already converted to unknown.
            if (isFromNode(fromApplication, toApplication)) {
                final boolean success = addNode(nodeBuilder, fromApplication);
                if (success) {
                    logger.debug("createSourceNode:{}", fromApplication);
                }
            } else {
                logger.warn("found rpc fromNode linkData:{}", linkData);
            }

            // FROM -> TO : TO is either a CLIENT or a node
            // create node when it's alias even if RPC
            if (isToNode(fromApplication, toApplication)) {
                final boolean success = addNode(nodeBuilder, toApplication);
                if (success) {
                    logger.debug("createTargetNode:{}", toApplication);
                }
            } else {
                logger.warn("found rpc toNode:{}", linkData);
            }
        }
    }
@author HyunGil Jeong
@author jaehong.kim
web/src/main/java/com/navercorp/pinpoint/web/applicationmap/nodes/NodeListFactory.java