Add createView method to GraphModel based on predicates

src/main/java/org/gephi/graph/api/GraphModel.java

@@ -19,6 +19,7 @@
 import java.io.DataOutput;
 import java.io.IOException;
 import java.time.ZoneId;
+import java.util.function.Predicate;
 import org.gephi.graph.impl.GraphModelImpl;
 
 /**
@@ -488,16 +489,38 @@ public static interface DefaultColumns {
 
     /**
      * Creates a new graph view.
+     * <p>
+     * By default, the view applies to both nodes and edges, so this is equivalent
+     * to {@link #createView(boolean, boolean) createView(true, true)}.
+     * <p>
+     * New views are by default empty, i.e. no nodes and no edges are visible in the
+     * view.
      *
      * @return newly created graph view
      */
     public GraphView createView();
 
+    /**
+     * Creates a new graph view.
+     * <p>
+     * The node and edge filters allows to restrict the view filtering to only nodes
+     * or only edges. If node only, all edges connected to included nodes will be
+     * included too. If edge only, all nodes are included but only the edges
+     * matching the view are included.
+     *
+     * @param nodeFilter predicate to filter nodes, or null to include all nodes
+     * @param edgeFilter predicate to filter edges, or null to include all edges
+     * @return newly created graph view
+     */
+    public GraphView createView(Predicate<Node> nodeFilter, Predicate<Edge> edgeFilter);
+
     /**
      * Creates a new graph view.
      * <p>
      * The node and edge parameters allows to restrict the view filtering to only
-     * nodes or only edges. By default, the view applies to both nodes and edges.
+     * nodes or only edges. If node only, all edges connected to included nodes will
+     * be included too. If edge only, all nodes are included but only the edges
+     * matching the view are included.
      *
      * @param node true to enable node view, false otherwise
      * @param edge true to enable edge view, false otherwise

src/main/java/org/gephi/graph/impl/GraphModelImpl.java

@@ -17,6 +17,7 @@
 
 import java.time.ZoneId;
 import java.util.Arrays;
+import java.util.function.Predicate;
 import org.gephi.graph.api.Configuration;
 import org.gephi.graph.api.DirectedGraph;
 import org.gephi.graph.api.DirectedSubgraph;
@@ -251,6 +252,11 @@ public GraphView createView() {
         return store.viewStore.createView();
     }
 
+    @Override
+    public GraphView createView(Predicate<Node> nodeFilter, Predicate<Edge> edgeFilter) {
+        return store.viewStore.createView(nodeFilter, edgeFilter);
+    }
+
     @Override
     public GraphView createView(boolean node, boolean edge) {
         return store.viewStore.createView(node, edge);

src/main/java/org/gephi/graph/impl/GraphViewDecorator.java

@@ -385,6 +385,9 @@ public boolean hasEdge(final Object id) {
 
     @Override
     public NodeIterable getNodes() {
+        if (!view.isNodeView()) {
+            return graphStore.getNodes();
+        }
         return new NodeIterableWrapper(() -> new NodeViewIterator(graphStore.nodeStore.iterator()),
                 NodeViewSpliterator::new, graphStore.getAutoLock());
     }

src/main/java/org/gephi/graph/impl/GraphViewImpl.java

@@ -22,6 +22,7 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.Objects;
+import java.util.function.Predicate;
 import org.gephi.graph.api.DirectedSubgraph;
 import org.gephi.graph.api.Edge;
 import org.gephi.graph.api.Graph;
@@ -77,6 +78,53 @@ public GraphViewImpl(final GraphStore store, boolean nodes, boolean edges) {
         this.interval = Interval.INFINITY_INTERVAL;
     }
 
+    public GraphViewImpl(final GraphStore store, Predicate<Node> nodePredicate, Predicate<Edge> edgePredicate) {
+        this(store, nodePredicate != null, edgePredicate != null);
+
+        // Fill - optimized with iterators and manual counting
+        if (nodePredicate != null) {
+            int count = 0;
+            for (Node node : graphStore.nodeStore) {
+                if (nodePredicate.test(node)) {
+                    nodeBitVector.set(node.getStoreId());
+                    count++;
+                }
+            }
+            nodeCount = count;
+            incrementNodeVersion();
+        }
+
+        // Process edges with iterator
+        int count = 0;
+        for (Edge edge : graphStore.edgeStore) {
+            // Cache store IDs
+            int sourceId = edge.getSource().getStoreId();
+            int targetId = edge.getTarget().getStoreId();
+
+            // Filter by node predicate if needed
+            if (nodePredicate != null && (!nodeBitVector.get(sourceId) || !nodeBitVector.get(targetId))) {
+                continue;
+            }
+
+            // Filter by edge predicate if needed
+            if (edgePredicate != null && !edgePredicate.test(edge)) {
+                continue;
+            }
+
+            edgeBitVector.set(edge.getStoreId());
+            int type = edge.getType();
+            typeCounts[type]++;
+            count++;
+
+            if (((EdgeImpl) edge).isMutual() && !edge.isSelfLoop() && containsEdge(graphStore.edgeStore
+                    .get(edge.getTarget(), edge.getSource(), type, false))) {
+                mutualEdgeTypeCounts[type]++;
+                mutualEdgesCount++;
+            }
+        }
+        edgeCount = count;
+    }
+
     public GraphViewImpl(final GraphViewImpl view, boolean nodes, boolean edges) {
         this.graphStore = view.graphStore;
         this.nodeView = nodes;
@@ -962,14 +1010,6 @@ protected void destroyAllObservers() {
         }
     }
 
-    protected void ensureNodeVectorSize(NodeImpl node) {
-        // BitSet automatically grows as needed, no manual resizing required
-    }
-
-    protected void ensureEdgeVectorSize(EdgeImpl edge) {
-        // BitSet automatically grows as needed, no manual resizing required
-    }
-
     protected void setEdgeType(EdgeImpl edgeImpl, int oldType, boolean wasMutual) {
         ensureTypeCountArrayCapacity(edgeImpl.type);
         typeCounts[oldType]--;

src/main/java/org/gephi/graph/impl/GraphViewStore.java

@@ -17,6 +17,7 @@
 
 import it.unimi.dsi.fastutil.ints.IntRBTreeSet;
 import it.unimi.dsi.fastutil.ints.IntSortedSet;
+import java.util.function.Predicate;
 import org.gephi.graph.api.DirectedSubgraph;
 import org.gephi.graph.api.Edge;
 import org.gephi.graph.api.Graph;
@@ -54,6 +55,17 @@ public GraphViewImpl createView() {
         return createView(true, true);
     }
 
+    public GraphViewImpl createView(Predicate<Node> nodeFilter, Predicate<Edge> edgeFilter) {
+        graphStore.autoWriteLock();
+        try {
+            GraphViewImpl graphView = new GraphViewImpl(graphStore, nodeFilter, edgeFilter);
+            addView(graphView);
+            return graphView;
+        } finally {
+            graphStore.autoWriteUnlock();
+        }
+    }
+
     public GraphViewImpl createView(boolean nodes, boolean edges) {
         graphStore.autoWriteLock();
         try {
@@ -232,58 +244,38 @@ public void destroyGraphObserver(GraphObserverImpl graphObserver) {
         graphViewImpl.destroyGraphObserver(graphObserver);
     }
 
-    protected void addNode(NodeImpl node) {
-        if (views.length > 0) {
-            for (GraphViewImpl view : views) {
-                if (view != null) {
-                    view.ensureNodeVectorSize(node);
-                }
-            }
-        }
-    }
-
     protected void removeNode(NodeImpl node) {
-        if (views.length > 0) {
-            for (GraphViewImpl view : views) {
-                if (view != null) {
-                    view.removeNode(node);
-                }
+        for (GraphViewImpl view : views) {
+            if (view != null) {
+                view.removeNode(node);
             }
         }
     }
 
     protected void addEdge(EdgeImpl edge) {
-        if (views.length > 0) {
-            for (GraphViewImpl view : views) {
-                if (view != null) {
-                    view.ensureEdgeVectorSize(edge);
-
-                    if (view.nodeView && !view.edgeView) {
-                        view.addEdgeInNodeView(edge);
-                    }
+        for (GraphViewImpl view : views) {
+            if (view != null) {
+                if (view.nodeView && !view.edgeView) {
+                    view.addEdgeInNodeView(edge);
                 }
             }
         }
     }
 
     protected void setEdgeType(EdgeImpl edge, int oldType, boolean wasMutual) {
-        if (views.length > 0) {
-            for (GraphViewImpl view : views) {
-                if (view != null) {
-                    if ((view.nodeView && !view.edgeView) || (view.edgeView && view.containsEdge(edge))) {
-                        view.setEdgeType(edge, oldType, wasMutual);
-                    }
+        for (GraphViewImpl view : views) {
+            if (view != null) {
+                if ((view.nodeView && !view.edgeView) || (view.edgeView && view.containsEdge(edge))) {
+                    view.setEdgeType(edge, oldType, wasMutual);
                 }
             }
         }
     }
 
     protected void removeEdge(EdgeImpl edge) {
-        if (views.length > 0) {
-            for (GraphViewImpl view : views) {
-                if (view != null) {
-                    view.removeEdge(edge);
-                }
+        for (GraphViewImpl view : views) {
+            if (view != null) {
+                view.removeEdge(edge);
             }
         }
     }

src/main/java/org/gephi/graph/impl/NodeStore.java

@@ -305,9 +305,6 @@ public boolean add(final Node n) {
                 currentBlock.add(node);
                 dictionary.put(node.getId(), node.storeId);
             }
-            if (viewStore != null) {
-                viewStore.addNode(node);
-            }
             node.indexAttributes();
 
             if (spatialIndex != null) {