/*
* Copyright 2008 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.wamblee.system.graph.component;
import java.util.List;
import org.wamblee.system.core.SystemAssemblyException;
import org.wamblee.system.graph.Edge;
import org.wamblee.system.graph.Graph;
import org.wamblee.system.graph.Node;
import org.wamblee.system.graph.Visitor;
/**
* Visitor that checks whether required and provided interfaces are matched
* appropriately:
*
* - Each required interface is connected to at most one provided interface
*
* - Required interfaces that are not optional must be connected to precisely
* one provided interface
*
*
* @author Erik Brakkee
*
*/
public class CheckRequiredProvidedMultiplicityVisitor implements Visitor {
private Graph _graph;
public CheckRequiredProvidedMultiplicityVisitor(Graph aGraph) {
_graph = aGraph;
}
@Override
public void visitEdge(Edge aEdge) {
// Empty
}
@Override
public void visitNode(Node aNode) {
if (aNode instanceof RequiredInterfaceNode) {
RequiredInterfaceNode required = (RequiredInterfaceNode) aNode;
List edges = _graph.findOutgoing(aNode);
if (edges.size() > 1) {
createDuplicateException("Multiple internal providers of interface found", aNode, edges);
}
if (edges.size() == 0 && !required.getRequired().isOptional()) {
throw new SystemAssemblyException(
aNode
+ ": mandatpory required interface not provided by other components started earlier");
}
} else if ( aNode instanceof ProvidedInterfaceNode) {
List edges = _graph.findOutgoing(aNode);
if ( edges.size() > 1) {
createDuplicateException("multiple internal matches for externally provided interface", aNode, edges);
}
if ( edges.size() == 0 ) {
throw new SystemAssemblyException(aNode + ": external provided interface is not provided internally");
}
}
}
private void createDuplicateException(String aMsg, Node aNode, List edges) {
StringBuffer buf = new StringBuffer();
buf.append(aNode
+ ": " + aMsg + ": ");
for (Edge edge : edges) {
buf.append(edge.getTo() + "/ ");
}
throw new SystemAssemblyException(buf.toString());
}
}