- if ( aNode instanceof ExternalRequiredInterfaceNode) {
- ExternalRequiredInterfaceNode required = (ExternalRequiredInterfaceNode) aNode;
- if ( !required.getRequired().isOptional() && required.getRequired().getProvider() == null) {
- throw new SystemAssemblyException(aNode + ": External required interface is not provided");
+ if (aNode instanceof ExternalRequiredInterfaceNode) {
+ ExternalRequiredInterfaceNode required = (ExternalRequiredInterfaceNode) aNode;
+ if (!required.getRequired().isOptional()
+ && required.getRequired().getProvider() == null) {
+ throw new SystemAssemblyException(aNode
+ + ": External required interface is not provided");
+ }
+
+ List<Edge> edges = _graph.findIncoming(aNode);
+
+ if (edges.isEmpty()) {
+ LOG.warn(aNode + ": Superfluous required interface");
+ }
+ for (Edge edge : edges) {
+ Node from = edge.getFrom();
+ assert from instanceof RequiredInterfaceNode;
+ RequiredInterfaceNode reqNode = (RequiredInterfaceNode)from;
+ if (!reqNode.getRequired().isOptional()
+ && required.getRequired().isOptional()) {
+ throw new SystemAssemblyException(
+ aNode
+ + ": externally required interface is optional but a corresponding internal required interface is mandatory: "
+ + reqNode);
+ }