getStaticElementsByTagName() - try to optimize the performance a bit …

…by not using live collections if not needed
HtmlUnit · Oct 27, 2024 · 4b0ea4a · 4b0ea4a
1 parent 6be084e
commit 4b0ea4a
Show file tree

Hide file tree

Showing 8 changed files with 40 additions and 19 deletions.
diff --git a/src/main/java/org/htmlunit/WebAssert.java b/src/main/java/org/htmlunit/WebAssert.java
@@ -414,7 +414,7 @@ public static void assertAllTabIndexAttributesSet(final HtmlPage page) {
             Arrays.asList("a", "area", "button", "input", "object", "select", "textarea");
 
         for (final String tag : tags) {
-            for (final HtmlElement element : page.getDocumentElement().getElementsByTagName(tag)) {
+            for (final HtmlElement element : page.getDocumentElement().getStaticElementsByTagName(tag)) {
                 final Short tabIndex = element.getTabIndex();
                 if (tabIndex == null || HtmlElement.TAB_INDEX_OUT_OF_BOUNDS.equals(tabIndex)) {
                     final String s = element.getAttributeDirect("tabindex");

diff --git a/src/main/java/org/htmlunit/html/DomElement.java b/src/main/java/org/htmlunit/html/DomElement.java
@@ -647,6 +647,23 @@ protected List<E> provideElements() {
         };
     }
 
+    /**
+     * <span style="color:red">INTERNAL API - SUBJECT TO CHANGE AT ANY TIME - USE AT YOUR OWN RISK.</span><br>
+     *
+     * @param <E> the specific HtmlElement type
+     * @param tagName The name of the tag to match on
+     * @return A list of matching elements; this is not a live list
+     */
+    public <E extends HtmlElement> List<E> getStaticElementsByTagName(final String tagName) {
+        final List<E> res = new ArrayList<>();
+        for (final HtmlElement elem : getHtmlElementDescendants()) {
+            if (elem.getLocalName().equalsIgnoreCase(tagName)) {
+                res.add((E) elem);
+            }
+        }
+        return res;
+    }
+
     /**
      * {@inheritDoc}
      * Not yet implemented.

diff --git a/src/main/java/org/htmlunit/html/DomNode.java b/src/main/java/org/htmlunit/html/DomNode.java
@@ -1059,7 +1059,6 @@ private void fireAddition(final DomNode domNode) {
             onAddedToDocumentFragment();
         }
 
-
         if (page == null || page.isDomChangeListenerInUse()) {
             fireNodeAdded(this, domNode);
         }

diff --git a/src/main/java/org/htmlunit/html/HtmlElement.java b/src/main/java/org/htmlunit/html/HtmlElement.java
@@ -926,7 +926,7 @@ public final <E extends HtmlElement> List<E> getElementsByAttribute(
      */
     public final HtmlElement appendChildIfNoneExists(final String tagName) {
         final HtmlElement child;
-        final List<HtmlElement> children = getElementsByTagName(tagName);
+        final List<HtmlElement> children = getStaticElementsByTagName(tagName);
         if (children.isEmpty()) {
             // Add a new child and return it.
             child = (HtmlElement) ((HtmlPage) getPage()).createElement(tagName);
@@ -946,7 +946,7 @@ public final HtmlElement appendChildIfNoneExists(final String tagName) {
      * @param i the index of the child to remove
      */
     public final void removeChild(final String tagName, final int i) {
-        final List<HtmlElement> children = getElementsByTagName(tagName);
+        final List<HtmlElement> children = getStaticElementsByTagName(tagName);
         if (i >= 0 && i < children.size()) {
             children.get(i).remove();
         }

diff --git a/src/main/java/org/htmlunit/html/HtmlMap.java b/src/main/java/org/htmlunit/html/HtmlMap.java
@@ -80,7 +80,7 @@ private HtmlImage findReferencingImage() {
         String name = getNameAttribute();
         if (null != page && StringUtils.isNotBlank(name)) {
             name = "#" + name.trim();
-            for (final HtmlElement elem : page.getDocumentElement().getElementsByTagName("img")) {
+            for (final HtmlElement elem : page.getDocumentElement().getStaticElementsByTagName("img")) {
                 final HtmlImage image = (HtmlImage) elem;
                 if (name.equals(image.getUseMapAttribute())) {
                     return image;

diff --git a/src/main/java/org/htmlunit/html/HtmlPage.java b/src/main/java/org/htmlunit/html/HtmlPage.java
@@ -1465,15 +1465,20 @@ private void executeDeferredScriptsIfNeeded() {
             return;
         }
         final DomElement doc = getDocumentElement();
-        final List<HtmlElement> elements = new ArrayList<>(doc.getElementsByTagName("script"));
-        for (final HtmlElement e : elements) {
-            if (e instanceof HtmlScript) {
-                final HtmlScript script = (HtmlScript) e;
+        final List<HtmlScript> scripts = new ArrayList<>();
+
+        // don't call getElementsByTagName() here because it creates a live collection
+        for (final HtmlElement elem : doc.getHtmlElementDescendants()) {
+            if ("script".equals(elem.getLocalName()) && (elem instanceof HtmlScript)) {
+                final HtmlScript script = (HtmlScript) elem;
                 if (script.isDeferred() && ATTRIBUTE_NOT_DEFINED != script.getSrcAttribute()) {
-                    ScriptElementSupport.executeScriptIfNeeded(script, true, true);
+                    scripts.add(script);
                 }
             }
         }
+        for (final HtmlScript script : scripts) {
+            ScriptElementSupport.executeScriptIfNeeded(script, true, true);
+        }
     }
 
     /**
@@ -1872,7 +1877,7 @@ static boolean isMappedElement(final Document document, final String attributeNa
     }
 
     private void calculateBase() {
-        final List<HtmlElement> baseElements = getDocumentElement().getElementsByTagName("base");
+        final List<HtmlElement> baseElements = getDocumentElement().getStaticElementsByTagName("base");
 
         base_ = null;
         for (final HtmlElement baseElement : baseElements) {
@@ -1930,7 +1935,7 @@ protected List<HtmlMeta> getMetaTags(final String httpEquiv) {
             return Collections.emptyList(); // weird case, for instance if document.documentElement has been removed
         }
         final String nameLC = httpEquiv.toLowerCase(Locale.ROOT);
-        final List<HtmlMeta> tags = getDocumentElement().getElementsByTagNameImpl("meta");
+        final List<HtmlMeta> tags = getDocumentElement().getStaticElementsByTagName("meta");
         final List<HtmlMeta> foundTags = new ArrayList<>();
         for (final HtmlMeta htmlMeta : tags) {
             if (nameLC.equals(htmlMeta.getHttpEquivAttribute().toLowerCase(Locale.ROOT))) {

diff --git a/src/main/java/org/htmlunit/html/HtmlSelect.java b/src/main/java/org/htmlunit/html/HtmlSelect.java
@@ -161,7 +161,7 @@ public List<HtmlOption> getSelectedOptions() {
      * @return all of the options in this select element
      */
     public List<HtmlOption> getOptions() {
-        return Collections.unmodifiableList(this.getElementsByTagNameImpl("option"));
+        return Collections.unmodifiableList(getStaticElementsByTagName("option"));
     }
 
     /**
@@ -171,15 +171,15 @@ public List<HtmlOption> getOptions() {
      * @return the option specified by the index
      */
     public HtmlOption getOption(final int index) {
-        return this.<HtmlOption>getElementsByTagNameImpl("option").get(index);
+        return this.<HtmlOption>getStaticElementsByTagName("option").get(index);
     }
 
     /**
      * Returns the number of options.
      * @return the number of options
      */
     public int getOptionSize() {
-        return getElementsByTagName("option").size();
+        return getStaticElementsByTagName("option").size();
     }
 
     /**
@@ -188,7 +188,7 @@ public int getOptionSize() {
      * @param newLength the new length property value
      */
     public void setOptionSize(final int newLength) {
-        final List<HtmlElement> elementList = getElementsByTagName("option");
+        final List<HtmlElement> elementList = getStaticElementsByTagName("option");
 
         for (int i = elementList.size() - 1; i >= newLength; i--) {
             elementList.get(i).remove();

diff --git a/src/main/java/org/htmlunit/javascript/host/html/HTMLTableElement.java b/src/main/java/org/htmlunit/javascript/host/html/HTMLTableElement.java
@@ -65,7 +65,7 @@ public void jsConstructor() {
      */
     @JsxGetter
     public HtmlUnitScriptable getCaption() {
-        final List<HtmlElement> captions = getDomNodeOrDie().getElementsByTagName("caption");
+        final List<HtmlElement> captions = getDomNodeOrDie().getStaticElementsByTagName("caption");
         if (captions.isEmpty()) {
             return null;
         }
@@ -96,7 +96,7 @@ public void setCaption(final Object o) {
      */
     @JsxGetter
     public HtmlUnitScriptable getTFoot() {
-        final List<HtmlElement> tfoots = getDomNodeOrDie().getElementsByTagName("tfoot");
+        final List<HtmlElement> tfoots = getDomNodeOrDie().getStaticElementsByTagName("tfoot");
         if (tfoots.isEmpty()) {
             return null;
         }
@@ -128,7 +128,7 @@ public void setTFoot(final Object o) {
      */
     @JsxGetter
     public HtmlUnitScriptable getTHead() {
-        final List<HtmlElement> theads = getDomNodeOrDie().getElementsByTagName("thead");
+        final List<HtmlElement> theads = getDomNodeOrDie().getStaticElementsByTagName("thead");
         if (theads.isEmpty()) {
             return null;
         }