public ProcessingNode buildNode(Configuration config) throws Exception 
{
          
        // Start by explicitely ordered children
        for (int i = 0; i <  orderedNames.length; i++) {
            Configuration childConfig = config.getChild(orderedNames[i], false);
            if (childConfig != null) {
                ProcessingNodeBuilder builder = this.treeBuilder.createNodeBuilder(childConfig);
                // Don't build them since "pipelines" is not present in this list
                builder.buildNode(childConfig);
            }
        }
        ProcessingNode pipelines = null;
        // Now build all those that have no particular order
        Configuration[] childConfigs = config.getChildren();
        loop: for (int i = 0; i <  childConfigs.length; i++) {
            Configuration childConfig = childConfigs[i];
            if (isChild(childConfig)) {
                // Is it in the ordered list ?
                for (int j = 0; j <  orderedNames.length; j++) {
                    if (orderedNames[j].equals(childConfig.getName())) {
                        // yep : already built above
                        continue loop;
                    }
                }
                ProcessingNodeBuilder builder = this.treeBuilder.createNodeBuilder(childConfig);
                ProcessingNode node = builder.buildNode(childConfig);
                if (node instanceof PipelinesNode) {
                    if (pipelines != null) {
                        String msg = "Only one 'pipelines' is allowed, at " + childConfig.getLocation();
                        throw new ConfigurationException(msg);
                    }
                    pipelines = node;
                }
            }
        }
        if (pipelines == null) {
            String msg = "Invalid sitemap : there must be a 'pipelines' at " + config.getLocation();
            throw new ConfigurationException(msg);
        }
        return pipelines;
}