Improved HTML parsing

editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/html/parser/XmlParser.java

 /*
  * Copyright (c) 2013, the Dart project authors.
  * 
  * Licensed under the Eclipse Public License v1.0 (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.eclipse.org/legal/epl-v10.html
  * 
  * 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
@@ skipping 50 matching lines @@
   /**
    * Answer the source being parsed.
    * 
    * @return the source
    */
   public Source getSource() {
     return source;
   }
 
   /**
+   * Create a node representing an attribute.
+   * 
+   * @param name the name of the attribute
+   * @param equals the equals sign, or {@code null} if there is no value
+   * @param value the value of the attribute
+   * @return the node that was created
+   */
+  protected XmlAttributeNode createAttributeNode(Token name, Token equals, Token value) {
+    return new XmlAttributeNode(name, equals, value);
+  }
+
+  /**
+   * Create a node representing a tag.
+   * 
+   * @param nodeStart the token marking the beginning of the tag
+   * @param tag the name of the tag
+   * @param attributes the attributes in the tag
+   * @param attributeEnd the token terminating the region where attributes can be
+   * @param tagNodes the children of the tag
+   * @param contentEnd the token that starts the closing tag
+   * @param closingTag the name of the tag that occurs in the closing tag
+   * @param nodeEnd the last token in the tag
+   * @return the node that was created
+   */
+  protected XmlTagNode createTagNode(Token nodeStart, Token tag, List<XmlAttributeNode> attributes,
+      Token attributeEnd, List<XmlTagNode> tagNodes, Token contentEnd, Token closingTag,
+      Token nodeEnd) {
+    return new XmlTagNode(
+        nodeStart,
+        tag,
+        attributes,
+        attributeEnd,
+        tagNodes,
+        contentEnd,
+        closingTag,
+        nodeEnd);
+  }
+
+  /**
    * Answer {@code true} if the specified tag is self closing and thus should never have content or
    * child tag nodes.
    * 
    * @param tag the tag (not {@code null})
    * @return {@code true} if self closing
    */
   protected boolean isSelfClosing(Token tag) {
     return false;
   }
 
@@ skipping 78 matching lines @@
     // String value
     Token value;
     if (currentToken.getType() == TokenType.STRING) {
       value = currentToken;
       currentToken = currentToken.getNext();
     } else {
       reportUnexpectedToken();
       value = insertSyntheticToken(STRING);
     }
 
-    return new XmlAttributeNode(name, equals, value);
+    return createAttributeNode(name, equals, value);
   }
 
   /**
    * Parse the stream for a sequence of attributes. This method advances the current token to the
    * next {@link TokenType#GT}, {@link TokenType#SLASH_GT}, or {@link TokenType#EOF}.
    * 
    * @return a collection of zero or more attributes (not {@code null}, contains no {@code null}s)
    */
   private List<XmlAttributeNode> parseAttributes() {
     TokenType type = currentToken.getType();
@@ skipping 87 matching lines @@
     if (currentToken.getType() == GT || currentToken.getType() == SLASH_GT) {
       attributeEnd = currentToken;
       currentToken = currentToken.getNext();
     } else {
       reportUnexpectedToken();
       attributeEnd = insertSyntheticToken(SLASH_GT);
     }
 
     // If the node has no children, then return the node
     if (attributeEnd.getType() == SLASH_GT || isSelfClosing(tag)) {
-      return new XmlTagNode(
+      return createTagNode(
           nodeStart,
           tag,
           attributes,
           attributeEnd,
           XmlTagNode.NO_TAG_NODES,
           currentToken,
           null,
           attributeEnd);
     }
 
@@ skipping 25 matching lines @@
     // Token ending node
     Token nodeEnd;
     if (currentToken.getType() == GT) {
       nodeEnd = currentToken;
       currentToken = currentToken.getNext();
     } else {
       reportUnexpectedToken();
       nodeEnd = insertSyntheticToken(GT);
     }
 
-    return new XmlTagNode(
+    return createTagNode(
         nodeStart,
         tag,
         attributes,
         attributeEnd,
         tagNodes,
         contentEnd,
         closingTag,
         nodeEnd);
   }
 
   /**
    * Report the current token as unexpected
    */
   private void reportUnexpectedToken() {
     // TODO (danrubel): report unexpected token
   }
 }