[graphl-cvs] graphl/src/org/mediavirus/graphl/graph/filter TransitiveCompressionFilter.java EdgeCompressionFilter.java FilteredGraph.java XPathFilteredGraph.java

[Flo L. <fl...@us...>]

Update of /cvsroot/graphl/graphl/src/org/mediavirus/graphl/graph/filter
In directory sc8-pr-cvs2.sourceforge.net:/tmp/cvs-serv16361/src/org/mediavirus/graphl/graph/filter

Modified Files:
	FilteredGraph.java XPathFilteredGraph.java 
Added Files:
	TransitiveCompressionFilter.java EdgeCompressionFilter.java 
Log Message:
backup commit - first implementation of xpath-based structural filters

--- NEW FILE: TransitiveCompressionFilter.java ---
/*
 * Created on 10.07.2006
 */

package org.mediavirus.graphl.graph.filter;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.jaxen.JaxenException;
import org.jaxen.XPath;

import org.mediavirus.graphl.graph.Edge;
import org.mediavirus.graphl.graph.GraphElement;
import org.mediavirus.graphl.graph.Node;
import org.mediavirus.graphl.jaxen.GraphlXPath;


public class TransitiveCompressionFilter {

    GraphlXPath selector;
    String edgeType;
    
    public TransitiveCompressionFilter(GraphlXPath selector, String newType) {
        this.selector = selector;
        this.edgeType = newType;
    }
    
    public String getEdgeType() {
        return edgeType;
    }
    
    public XPath getSelector() {
        return selector;
    }
    
    public void filterGraph(XPathFilteredGraph graph) {
        try {
            Object paths = selector.selectPaths(graph);
            if (paths instanceof List) {
                for (List path : (List<List>)paths) {
                    if (path.get(0) instanceof Node && path.get(path.size()-1) instanceof Node) {
                        
                        Node startNode = (Node)path.get(0);
                        Node endNode = (Node)path.get(path.size()-1);
                        Edge newEdge = graph.createEdge(startNode, endNode);
                        newEdge.setType(edgeType);
                        
                        path.remove(path.size()-1);
                        path.remove(0);
                        graph.removeElements(path);
                        
                        graph.addElements(null, Collections.singleton(newEdge));
                    }
                }
            }
        }
        catch (JaxenException jexdasdu) {
            System.err.println("Error evaluation XPath " + selector.toString() + " on graph: " + jexdasdu);
        }
    }
    
}

--- NEW FILE: EdgeCompressionFilter.java ---
/*
 * Created on 10.07.2006
 */

package org.mediavirus.graphl.graph.filter;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.jaxen.JaxenException;
import org.jaxen.XPath;
import org.mediavirus.graphl.graph.Edge;
import org.mediavirus.graphl.graph.GraphElement;
import org.mediavirus.graphl.graph.Node;


public class EdgeCompressionFilter {

    XPath selector;
    XPath groupBy;
    String newType;
    
    public EdgeCompressionFilter(XPath selector, XPath groupBy, String newType) {
        this.selector = selector;
        this.groupBy = groupBy;
        this.newType = newType;
    }
    
    public XPath getGroupBy() {
        return groupBy;
    }
    
    public String getNewType() {
        return newType;
    }
    
    public XPath getSelector() {
        return selector;
    }
    
    public void filterGraph(XPathFilteredGraph graph) {
        try {
            Object elements = selector.evaluate(graph);
            if (elements instanceof List && ((List)elements).size() > 1) {
                // this maps edges by to and from nodes
                Map<Set<Node>, List<Edge>> groups = new HashMap<Set<Node>, List<Edge>>();
                for (Edge edge : (List<Edge>)elements) {
                    Object groupElements = groupBy.evaluate(edge);
                    Set nodeSet;
                    if (groupElements instanceof List) {
                        nodeSet = new HashSet((List)groupElements);
                    }
                    else {
                        nodeSet = Collections.singleton(groupElements);
                    }
                    
                    if (groups.get(nodeSet) == null) {
                        groups.put(nodeSet, new ArrayList<Edge>());
                    }
                    groups.get(nodeSet).add(edge);

                }
                List<Edge> newEdges = new ArrayList<Edge>();
                List<Edge> edgesToRemove = new ArrayList<Edge>();
                for (Set<Node> group : groups.keySet()) {
                    // only compress if more than 1 edge and exactly 2 endnodes
                    if (group.size() == 2 && groups.get(group).size() > 1) {
                        Node[] endnodes = new Node[2];
                        int i = 0;
                        for (Iterator<Node> groupIter = group.iterator(); groupIter.hasNext();) {
                            Node node = groupIter.next();
                            endnodes[i++] = node;
                            if (i==2) break;                           
                        }
                        Edge newEdge = graph.getSource().createEdge(endnodes[0], endnodes[1]);
                        newEdge.setType(newType);                   
                        newEdges.add(newEdge);
                        edgesToRemove.addAll(groups.get(group));
                    }
                    else if (group.size() != 2) {
                        System.err.println("Warning: Edge compression grouping expression (" + groupBy.toString() + ") does not result in 2 elements - ignoring compression.");
                    }
                }
                graph.removeElements(edgesToRemove);
                graph.addElements(null, newEdges);
            }
        }
        catch (JaxenException jexdasdu) {
            System.err.println("Error evaluation XPath " + selector.toString() + " on graph: " + jexdasdu);
        }
    }
    
}

Index: XPathFilteredGraph.java
===================================================================
RCS file: /cvsroot/graphl/graphl/src/org/mediavirus/graphl/graph/filter/XPathFilteredGraph.java,v
retrieving revision 1.1
retrieving revision 1.2
diff -C2 -d -r1.1 -r1.2
*** XPathFilteredGraph.java	3 Jul 2006 15:26:33 -0000	1.1
--- XPathFilteredGraph.java	11 Jul 2006 18:34:31 -0000	1.2
***************
*** 22,25 ****
--- 22,27 ----
      List<XPathFilter> omissionFilters = new ArrayList<XPathFilter>();
      List<NodeCompressionFilter> nodeCompressionFilters = new ArrayList<NodeCompressionFilter>();
+     List<EdgeCompressionFilter> edgeCompressionFilters = new ArrayList<EdgeCompressionFilter>();
+     List<TransitiveCompressionFilter> transitiveCompressionFilters = new ArrayList<TransitiveCompressionFilter>();
      
      List<Node> overlayNodes = new ArrayList<Node>();
***************
*** 39,48 ****
      }
      
!     public void addEdgeCompressionFilter(XPath selector, String newType) {
!         
      }
      
!     public void addTransitiveCompressionFilter(XPath selector, String newType) {
!         
      }
      
--- 41,50 ----
      }
      
!     public void addEdgeCompressionFilter(EdgeCompressionFilter filter) {
!         edgeCompressionFilters.add(filter);
      }
      
!     public void addTransitiveCompressionFilter(TransitiveCompressionFilter filter) {
!         transitiveCompressionFilters.add(filter);
      }
      
***************
*** 70,73 ****
--- 72,81 ----
              filter.filterGraph(this);            
          }
+         for (EdgeCompressionFilter filter : edgeCompressionFilters) {
+             filter.filterGraph(this);            
+         }
+         for (TransitiveCompressionFilter filter : transitiveCompressionFilters) {
+             filter.filterGraph(this);            
+         }
          
          fireGraphContentsChanged();     

Index: FilteredGraph.java
===================================================================
RCS file: /cvsroot/graphl/graphl/src/org/mediavirus/graphl/graph/filter/FilteredGraph.java,v
retrieving revision 1.7
retrieving revision 1.8
diff -C2 -d -r1.7 -r1.8
*** FilteredGraph.java	3 Jul 2006 15:26:33 -0000	1.7
--- FilteredGraph.java	11 Jul 2006 18:34:31 -0000	1.8
***************
*** 247,252 ****
  
      public void addElements(Collection<Node> nodes, Collection<Edge> edges) {
!         cachedNodes.addAll(nodes);
!         cachedEdges.addAll(edges);
          sourceGraph.addElements(nodes, edges);
      }
--- 247,252 ----
  
      public void addElements(Collection<Node> nodes, Collection<Edge> edges) {
!         if (nodes != null) cachedNodes.addAll(nodes);
!         if (edges != null) cachedEdges.addAll(edges);
          sourceGraph.addElements(nodes, edges);
      }