1ce53d0732e4de4d67f35785ed04604781c71215
[utils] /
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 }