perf: replace recursion with iteration

Author: rubenporras

com.avaloq.tools.ddk.xtext/src/com/avaloq/tools/ddk/xtext/resource/persistence/ProxyCompositeNode.java

@@ -11,7 +11,9 @@
 package com.avaloq.tools.ddk.xtext.resource.persistence;
 
 import java.io.IOException;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
+import java.util.Deque;
 import java.util.List;
 
 import org.eclipse.emf.common.notify.Adapter;
@@ -21,8 +23,9 @@
 import org.eclipse.emf.common.util.TreeIterator;
 import org.eclipse.emf.common.util.WrappedException;
 import org.eclipse.emf.ecore.EObject;
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.emf.ecore.impl.EClassImpl;
 import org.eclipse.emf.ecore.resource.Resource;
-import org.eclipse.emf.ecore.util.EContentsEList.FeatureIterator;
 import org.eclipse.xtext.nodemodel.BidiIterable;
 import org.eclipse.xtext.nodemodel.BidiTreeIterable;
 import org.eclipse.xtext.nodemodel.BidiTreeIterator;
@@ -80,24 +83,45 @@ static void installProxyNodeModel(final Resource resource) {
     ProxyCompositeNode rootNode = installProxyNodeModel(root, idToEObjectMap);
     idToEObjectMap.trimToSize();
     rootNode.idToEObjectMap = idToEObjectMap;
-
     if (resource instanceof XtextResource) {
       ((XtextResource) resource).setParseResult(new ParseResult(root, rootNode, false));
     }
   }
 
   private static ProxyCompositeNode installProxyNodeModel(final EObject eObject, final List<EObject> map) {
-    ProxyCompositeNode result = new ProxyCompositeNode();
-    eObject.eAdapters().add(result);
+    Deque<EObject> deque = new ArrayDeque<>();
+    deque.push(eObject);
+    ProxyCompositeNode rootComposite = new ProxyCompositeNode();
+    eObject.eAdapters().add(rootComposite);
     map.add(eObject);
 
-    for (FeatureIterator<EObject> it = (FeatureIterator<EObject>) eObject.eContents().iterator(); it.hasNext();) {
-      EObject child = it.next();
-      if (!it.feature().isTransient()) {
-        installProxyNodeModel(child, map);
+    while (!deque.isEmpty()) {
+      EObject nextEObject = deque.pop();
+      EStructuralFeature[] structuralFeatures = ((EClassImpl.FeatureSubsetSupplier) nextEObject.eClass().getEAllStructuralFeatures()).containments();
+      if (structuralFeatures != null) {
+        for (int i = structuralFeatures.length - 1; i >= 0; i--) {
+          EStructuralFeature eStructuralFeature = structuralFeatures[i];
+          if (!eStructuralFeature.isTransient()) {
+            Object child = nextEObject.eGet(eStructuralFeature, false);
+            if (child instanceof EObject singleChild) {
+              singleChild.eAdapters().add(new ProxyCompositeNode());
+              map.add(singleChild);
+              deque.push(singleChild);
+            } else if (child instanceof EList listChild) {
+              for (int j = listChild.size() - 1; j >= 0; j--) {
+                EObject singleChild = (EObject) listChild.get(j);
+                singleChild.eAdapters().add(new ProxyCompositeNode());
+                map.add(singleChild);
+                deque.push(singleChild);
+              }
+            } else if (child != null) {
+              throw new IllegalStateException("Unexpected class " + child.getClass()); //$NON-NLS-1$
+            }
+          }
+        }
       }
     }
-    return result;
+    return rootComposite;
   }
 
   /**