wamblee.org Git - utils/blob - system/general/src/main/java/org/wamblee/system/graph/component/CheckExternallyRequiredVisitor.java

   1 /*
   2  * Copyright 2008 the original author or authors.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.wamblee.system.graph.component;
  17
  18 import java.util.List;
  19
  20 import org.apache.commons.logging.Log;
  21 import org.apache.commons.logging.LogFactory;
  22 import org.wamblee.system.core.SystemAssemblyException;
  23 import org.wamblee.system.graph.Edge;
  24 import org.wamblee.system.graph.Graph;
  25 import org.wamblee.system.graph.Node;
  26 import org.wamblee.system.graph.Visitor;
  27
  28 /**
  29  * Visitor that checks whether all required external interfaces of the container
  30  * are provided.
  31  *
  32  * @author Erik Brakkee
  33  *
  34  */
  35 public class CheckExternallyRequiredVisitor implements Visitor {
  36
  37     private Log LOG = LogFactory.getLog(CheckExternallyRequiredVisitor.class);
  38
  39     private Graph graph;
  40
  41     public CheckExternallyRequiredVisitor(Graph aGraph) {
  42         graph = aGraph;
  43     }
  44
  45     @Override
  46     public void visitEdge(Edge aEdge) {
  47         // Empty.
  48     }
  49
  50     @Override
  51     public void visitNode(Node aNode) {
  52         if (aNode instanceof ExternalRequiredInterfaceNode) {
  53             ExternalRequiredInterfaceNode required = (ExternalRequiredInterfaceNode) aNode;
  54             if (!required.getRequired().isOptional()
  55                     && required.getRequired().getProvider() == null) {
  56                 throw new SystemAssemblyException(aNode
  57                         + ": External required interface is not provided");
  58             }
  59
  60             List<Edge> edges = graph.findIncoming(aNode);
  61
  62             if (edges.isEmpty()) {
  63                 LOG.warn(aNode + ": Superfluous required interface");
  64             }
  65             for (Edge edge : edges) {
  66                 Node from = edge.getFrom();
  67                 assert from instanceof RequiredInterfaceNode;
  68                 RequiredInterfaceNode reqNode = (RequiredInterfaceNode)from;
  69                 if (!reqNode.getRequired().isOptional()
  70                         && required.getRequired().isOptional()) {
  71                     throw new SystemAssemblyException(
  72                             aNode
  73                                     + ": externally required interface is optional but a corresponding internal required interface is mandatory: "
  74                                     + reqNode);
  75                 }
  76             }
  77         }
  78     }
  79
  80 }