AbstractEdgeSource.java

package org.apache.maven.diagrams.connectors.classes.edge_source;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

import org.apache.maven.diagrams.connectors.classes.ClassNodesRepository;
import org.apache.maven.diagrams.connectors.classes.config.ClassesConnectorConfiguration;
import org.apache.maven.diagrams.connectors.classes.filter.FilterRepository;
import org.apache.maven.diagrams.connectors.classes.graph.ClassEdge;
import org.apache.maven.diagrams.connectors.classes.graph.ClassNode;
import org.apache.maven.diagrams.connectors.classes.model.ClassModel;
import org.codehaus.plexus.logging.AbstractLogEnabled;

/**
 * @author <a href="mailto:ptab@newitech.com">Piotr Tabor</a>
 * @version $Id$
 */
public abstract class AbstractEdgeSource extends AbstractLogEnabled implements EdgeSource
{

    /**
     * The object's instance that answers if the given class should be added to the resulting graph or be skipped (with
     * keeping edges or not)
     */
    private FilterRepository filterRepository;

    /**
     * The object's instance that provides and caches important informations ( {@link ClassModel}) for the given class
     * name
     */
    private ClassNodesRepository classNodesRepository;

    /**
     * The whole ClassesConnecector's configuration
     */
    private ClassesConnectorConfiguration configuration;

    /*
     * (non-Javadoc)
     * 
     * @see org.apache.maven.diagrams.connectors.classes.edge_source.EdgeSource#configure(org.apache.maven.diagrams.connectors.classes.filter.FilterRepository,
     *      org.apache.maven.diagrams.connectors.classes.ClassNodesRepository,
     *      org.apache.maven.diagrams.connectors.classes.config.ClassesConnectorConfiguration)
     */
    public void configure( FilterRepository a_filterRepository, ClassNodesRepository a_classNodesRepository,
                           ClassesConnectorConfiguration a_configuration )
    {
        filterRepository = a_filterRepository;
        classNodesRepository = a_classNodesRepository;
        configuration = a_configuration;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.apache.maven.diagrams.connectors.classes.edge_source.EdgeSource#calculateEdges(java.util.Set)
     */
    public Set<ClassEdge> calculateEdges( Set<ClassNode> resultNodes )
    {
        LinkedList<ClassNode> queue = new LinkedList<ClassNode>( resultNodes );
        Set<ClassEdge> result = new HashSet<ClassEdge>();
        Set<ClassNode> done = new HashSet<ClassNode>();

        while ( !queue.isEmpty() )
        {
            ClassNode head = queue.poll();
            if ( !done.contains( head ) )
            {
                done.add( head );
                List<ClassEdge> newEdges = createOutgoingEdges( head );
                for ( ClassEdge newEdge : newEdges )
                {
                    if ( resultNodes.contains( newEdge.getEndNode() ) )
                    {
                        result.add( newEdge );
                    }
                    else
                    {
                        switch ( canAddNode( (ClassNode) newEdge.getEndNode() ) )
                        {
                            case ADD_NODE_AND_RESOLVE_TRANSITIVES:
                                resultNodes.add( (ClassNode) newEdge.getEndNode() );
                                /* no break */
                            case ADD_NODE_DONT_RESOLVE_TRANSITIVES:
                                queue.add( (ClassNode) newEdge.getEndNode() );
                                result.add( newEdge );
                                break;
                            case DONT_ADD_NODE:
                        }
                    }
                }
            }
        }
        return result;
    }

    /**
     * Implementation of this method should prepare list of outgoing edges from the given node. The method shouldn't
     * check if the target node already exists in the graph. The calculate edges method will check that depending on
     * results of canAddNode method.
     * 
     * The implementation can call
     * 
     * @param sourceNode -
     *            node from that we need edges.
     * @return
     */
    protected abstract List<ClassEdge> createOutgoingEdges( ClassNode sourceNode );

    /**
     * The method obtains information what can be done with the given node (if it should be added to the graph or
     * skipped (with all without its dependencies))
     * 
     * @param node
     * @return
     */
    protected abstract AddNodeStatus canAddNode( ClassNode node );

    protected static enum AddNodeStatus
    {
        /** Add the node to graph and process its dependences */
        ADD_NODE_AND_RESOLVE_TRANSITIVES,

        /** Add the node to graph and don't process its dependences */
        ADD_NODE_DONT_RESOLVE_TRANSITIVES,

        /** Don't add the node and don't work on its transitive dependencies */
        DONT_ADD_NODE
    }

    /* --------------------- Getters and setters----------------------------- */

    /*
     * (non-Javadoc)
     * 
     * @see org.apache.maven.diagrams.connectors.classes.edge_source.EdgeSource#getFilterRepository()
     */
    public FilterRepository getFilterRepository()
    {
        return filterRepository;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.apache.maven.diagrams.connectors.classes.edge_source.EdgeSource#getClassNodesRepository()
     */
    public ClassNodesRepository getClassNodesRepository()
    {
        return classNodesRepository;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.apache.maven.diagrams.connectors.classes.edge_source.EdgeSource#getConfiguration()
     */
    public ClassesConnectorConfiguration getConfiguration()
    {
        return configuration;
    }
};