Class ParentNode

All Implemented Interfaces:
Cloneable, EventTarget, Node, NodeList
Direct Known Subclasses:
CoreDocumentImpl, DocumentFragmentImpl, DocumentTypeImpl, ElementImpl, EntityImpl, EntityReferenceImpl

public abstract class ParentNode extends ChildNode
ParentNode inherits from ChildNode and adds the capability of having child nodes. Not every node in the DOM can have children, so only nodes that can should inherit from this class and pay the price for it.

ParentNode, just like NodeImpl, also implements NodeList, so it can return itself in response to the getChildNodes() query. This eliminiates the need for a separate ChildNodeList object. Note that this is an IMPLEMENTATION DETAIL; applications should _never_ assume that this identity exists. On the other hand, subclasses may need to override this, in case of conflicting names. This is the case for the classes HTMLSelectElementImpl and HTMLFormElementImpl of the HTML DOM.

While we have a direct reference to the first child, the last child is stored as the previous sibling of the first child. First child nodes are marked as being so, and getNextSibling hides this fact.

Note: Not all parent nodes actually need to also be a child. At some point we used to have ParentNode inheriting from NodeImpl and another class called ChildAndParentNode that inherited from ChildNode. But due to the lack of multiple inheritance a lot of code had to be duplicated which led to a maintenance nightmare. At the same time only a few nodes (Document, DocumentFragment, Entity, and Attribute) cannot be a child so the gain in memory wasn't really worth it. The only type for which this would be the case is Attribute, but we deal with there in another special way, so this is not applicable.

This class doesn't directly support mutation events, however, it notifies the document when mutations are performed so that the document class do so.

WARNING: Some of the code here is partially duplicated in AttrImpl, be careful to keep these two classes in sync!

  • Field Details

    • ownerDocument

      protected CoreDocumentImpl ownerDocument
      Owner document.
    • firstChild

      protected ChildNode firstChild
      First child.
    • fNodeListCache

      protected NodeListCache fNodeListCache
      NodeList cache
  • Constructor Details

    • ParentNode

      protected ParentNode(CoreDocumentImpl ownerDocument)
      No public constructor; only subclasses of ParentNode should be instantiated, and those normally via a Document's factory methods
      Parameters:
      ownerDocument - the owner document
  • Method Details

    • cloneNode

      public Node cloneNode(boolean deep)
      Returns a duplicate of a given node. You can consider this a generic "copy constructor" for nodes. The newly returned object should be completely independent of the source object's subtree, so changes in one after the clone has been made will not affect the other.

      Note: since we never have any children deep is meaningless here, ParentNode overrides this behavior. Returns a duplicate of a given node. You can consider this a generic "copy constructor" for nodes. The newly returned object should be completely independent of the source object's subtree, so changes in one after the clone has been made will not affect the other.

      Note: since we never have any children deep is meaningless here, ParentNode overrides this behavior. Returns a duplicate of a given node. You can consider this a generic "copy constructor" for nodes. The newly returned object should be completely independent of the source object's subtree, so changes in one after the clone has been made will not affect the other.

      Example: Cloning a Text node will copy both the node and the text it contains.

      Example: Cloning something that has children -- Element or Attr, for example -- will _not_ clone those children unless a "deep clone" has been requested. A shallow clone of an Attr node will yield an empty Attr of the same name.

      NOTE: Clones will always be read/write, even if the node being cloned is read-only, to permit applications using only the DOM API to obtain editable copies of locked portions of the tree.

      Specified by:
      cloneNode in interface Node
      Overrides:
      cloneNode in class ChildNode
      See Also:
    • getOwnerDocument

      public Document getOwnerDocument()
      Find the Document that this Node belongs to (the document in whose context the Node was created). The Node may or may not currently be part of that Document's actual contents. Find the Document that this Node belongs to (the document in whose context the Node was created). The Node may or may not currently be part of that Document's actual contents.
      Specified by:
      getOwnerDocument in interface Node
      Overrides:
      getOwnerDocument in class NodeImpl
    • ownerDocument

      CoreDocumentImpl ownerDocument()
      same as above but returns internal type and this one is not overridden by CoreDocumentImpl to return null Same as above but returns internal type and this one is not overridden by CoreDocumentImpl to return null
      Overrides:
      ownerDocument in class NodeImpl
    • setOwnerDocument

      protected void setOwnerDocument(CoreDocumentImpl doc)
      NON-DOM set the ownerDocument of this node and its children
      Overrides:
      setOwnerDocument in class NodeImpl
    • hasChildNodes

      public boolean hasChildNodes()
      Test whether this node has any children. Convenience shorthand for (Node.getFirstChild()!=null)

      By default we do not have any children, ParentNode overrides this. Test whether this node has any children. Convenience shorthand for (Node.getFirstChild()!=null)

      Specified by:
      hasChildNodes in interface Node
      Overrides:
      hasChildNodes in class NodeImpl
      See Also:
    • getChildNodes

      public NodeList getChildNodes()
      Obtain a NodeList enumerating all children of this node. If there are none, an (initially) empty NodeList is returned.

      NodeLists are "live"; as children are added/removed the NodeList will immediately reflect those changes. Also, the NodeList refers to the actual nodes, so changes to those nodes made via the DOM tree will be reflected in the NodeList and vice versa.

      In this implementation, Nodes implement the NodeList interface and provide their own getChildNodes() support. Other DOMs may solve this differently. Obtain a NodeList enumerating all children of this node. If there are none, an (initially) empty NodeList is returned.

      NodeLists are "live"; as children are added/removed the NodeList will immediately reflect those changes. Also, the NodeList refers to the actual nodes, so changes to those nodes made via the DOM tree will be reflected in the NodeList and vice versa.

      In this implementation, Nodes implement the NodeList interface and provide their own getChildNodes() support. Other DOMs may solve this differently.

      Specified by:
      getChildNodes in interface Node
      Overrides:
      getChildNodes in class NodeImpl
    • getFirstChild

      public Node getFirstChild()
      The first child of this Node, or null if none.

      By default we do not have any children, ParentNode overrides this.

      Specified by:
      getFirstChild in interface Node
      Overrides:
      getFirstChild in class NodeImpl
      See Also:
    • getLastChild

      public Node getLastChild()
      The first child of this Node, or null if none.

      By default we do not have any children, ParentNode overrides this.

      Specified by:
      getLastChild in interface Node
      Overrides:
      getLastChild in class NodeImpl
      See Also:
    • lastChild

      final ChildNode lastChild()
    • insertBefore

      public Node insertBefore(Node newChild, Node refChild) throws DOMException
      Move one or more node(s) to our list of children. Note that this implicitly removes them from their previous parent.

      By default we do not accept any children, ParentNode overrides this. Move one or more node(s) to our list of children. Note that this implicitly removes them from their previous parent.

      Specified by:
      insertBefore in interface Node
      Overrides:
      insertBefore in class NodeImpl
      Parameters:
      newChild - The Node to be moved to our subtree. As a convenience feature, inserting a DocumentNode will instead insert all its children.
      refChild - Current child which newChild should be placed immediately before. If refChild is null, the insertion occurs after all existing Nodes, like appendChild().
      Returns:
      newChild, in its new state (relocated, or emptied in the case of DocumentNode.)
      Throws:
      DOMException - HIERARCHY_REQUEST_ERR if newChild is of a type that shouldn't be a child of this node, or if newChild is an ancestor of this node.
      DOMException - WRONG_DOCUMENT_ERR if newChild has a different owner document than we do.
      DOMException - NOT_FOUND_ERR if refChild is not a child of this node.
      DOMException - NO_MODIFICATION_ALLOWED_ERR if this node is read-only.
      See Also:
    • internalInsertBefore

      Node internalInsertBefore(Node newChild, Node refChild, boolean replace) throws DOMException
      Throws:
      DOMException
    • removeChild

      public Node removeChild(Node oldChild) throws DOMException
      Remove a child from this Node. The removed child's subtree remains intact so it may be re-inserted elsewhere.

      By default we do not have any children, ParentNode overrides this. Remove a child from this Node. The removed child's subtree remains intact so it may be re-inserted elsewhere.

      Specified by:
      removeChild in interface Node
      Overrides:
      removeChild in class NodeImpl
      Returns:
      oldChild, in its new state (removed).
      Throws:
      DOMException - NOT_FOUND_ERR if oldChild is not a child of this node.
      DOMException - NO_MODIFICATION_ALLOWED_ERR if this node is read-only.
      See Also:
    • internalRemoveChild

      Node internalRemoveChild(Node oldChild, boolean replace) throws DOMException
      Throws:
      DOMException
    • replaceChild

      public Node replaceChild(Node newChild, Node oldChild) throws DOMException
      Make newChild occupy the location that oldChild used to have. Note that newChild will first be removed from its previous parent, if any. Equivalent to inserting newChild before oldChild, then removing oldChild.

      By default we do not have any children, ParentNode overrides this. Make newChild occupy the location that oldChild used to have. Note that newChild will first be removed from its previous parent, if any. Equivalent to inserting newChild before oldChild, then removing oldChild.

      Specified by:
      replaceChild in interface Node
      Overrides:
      replaceChild in class NodeImpl
      Returns:
      oldChild, in its new state (removed).
      Throws:
      DOMException - HIERARCHY_REQUEST_ERR if newChild is of a type that shouldn't be a child of this node, or if newChild is one of our ancestors.
      DOMException - WRONG_DOCUMENT_ERR if newChild has a different owner document than we do.
      DOMException - NOT_FOUND_ERR if oldChild is not a child of this node.
      DOMException - NO_MODIFICATION_ALLOWED_ERR if this node is read-only.
      See Also:
    • getTextContent

      public String getTextContent() throws DOMException
      Description copied from class: NodeImpl
      This attribute returns the text content of this node and its descendants. When it is defined to be null, setting it has no effect. When set, any possible children this node may have are removed and replaced by a single Text node containing the string this attribute is set to. On getting, no serialization is performed, the returned string does not contain any markup. No whitespace normalization is performed, the returned string does not contain the element content whitespaces . Similarly, on setting, no parsing is performed either, the input string is taken as pure textual content.
      The string returned is made of the text content of this node depending on its type, as defined below:
      Node type Content
      ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, DOCUMENT_FRAGMENT_NODE concatenation of the textContent attribute value of every child node, excluding COMMENT_NODE and PROCESSING_INSTRUCTION_NODE nodes
      ATTRIBUTE_NODE, TEXT_NODE, CDATA_SECTION_NODE, COMMENT_NODE, PROCESSING_INSTRUCTION_NODE nodeValue
      DOCUMENT_NODE, DOCUMENT_TYPE_NODE, NOTATION_NODE null
      Specified by:
      getTextContent in interface Node
      Overrides:
      getTextContent in class NodeImpl
      Throws:
      DOMException - DOMSTRING_SIZE_ERR: Raised when it would return more characters than fit in a DOMString variable on the implementation platform.
    • getTextContent

      void getTextContent(StringBuilder builder) throws DOMException
      Overrides:
      getTextContent in class NodeImpl
      Throws:
      DOMException
    • hasTextContent

      static final boolean hasTextContent(Node child)
    • setTextContent

      public void setTextContent(String textContent) throws DOMException
      Description copied from class: NodeImpl
      This attribute returns the text content of this node and its descendants. When it is defined to be null, setting it has no effect. When set, any possible children this node may have are removed and replaced by a single Text node containing the string this attribute is set to. On getting, no serialization is performed, the returned string does not contain any markup. No whitespace normalization is performed, the returned string does not contain the element content whitespaces . Similarly, on setting, no parsing is performed either, the input string is taken as pure textual content.
      The string returned is made of the text content of this node depending on its type, as defined below:
      Node type Content
      ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, DOCUMENT_FRAGMENT_NODE concatenation of the textContent attribute value of every child node, excluding COMMENT_NODE and PROCESSING_INSTRUCTION_NODE nodes
      ATTRIBUTE_NODE, TEXT_NODE, CDATA_SECTION_NODE, COMMENT_NODE, PROCESSING_INSTRUCTION_NODE nodeValue
      DOCUMENT_NODE, DOCUMENT_TYPE_NODE, NOTATION_NODE null
      Specified by:
      setTextContent in interface Node
      Overrides:
      setTextContent in class NodeImpl
      Throws:
      DOMException - DOMSTRING_SIZE_ERR: Raised when it would return more characters than fit in a DOMString variable on the implementation platform.
    • nodeListGetLength

      int nodeListGetLength()
      Count the immediate children of this node. Use to implement NodeList.getLength().
      Returns:
      the length
    • getLength

      public int getLength()
      NodeList method: Count the immediate children of this node

      By default we do not have any children, ParentNode overrides this. NodeList method: Count the immediate children of this node

      Specified by:
      getLength in interface NodeList
      Overrides:
      getLength in class NodeImpl
      Returns:
      int
    • nodeListItem

      Node nodeListItem(int index)
      Parameters:
      index - the index
      Returns:
      the Nth immediate child of this node, or null if the index is out of bounds. Use to implement NodeList.item().
    • item

      public Node item(int index)
      NodeList method: Return the Nth immediate child of this node, or null if the index is out of bounds.

      By default we do not have any children, ParentNode overrides this. NodeList method: Return the Nth immediate child of this node, or null if the index is out of bounds.

      Specified by:
      item in interface NodeList
      Overrides:
      item in class NodeImpl
      Parameters:
      index - int
      Returns:
      org.w3c.dom.Node
    • getChildNodesUnoptimized

      protected final NodeList getChildNodesUnoptimized()
      Create a NodeList to access children that is use by subclass elements that have methods named getLength() or item(int). ChildAndParentNode optimizes getChildNodes() by implementing NodeList itself. However if a subclass Element implements methods with the same name as the NodeList methods, they will override the actually methods in this class.
      Returns:
      a node list
    • isEqualNode

      public boolean isEqualNode(Node arg)
      Tests whether two nodes are equal.
      This method tests for equality of nodes, not sameness (i.e., whether the two nodes are references to the same object) which can be tested with Node.isSameNode. All nodes that are the same will also be equal, though the reverse may not be true.
      Two nodes are equal if and only if the following conditions are satisfied: The two nodes are of the same type.The following string attributes are equal: nodeName, localName, namespaceURI, prefix, nodeValue , baseURI. This is: they are both null, or they have the same length and are character for character identical. The attributes NamedNodeMaps are equal. This is: they are both null, or they have the same length and for each node that exists in one map there is a node that exists in the other map and is equal, although not necessarily at the same index.The childNodes NodeLists are equal. This is: they are both null, or they have the same length and contain equal nodes at the same index. This is true for Attr nodes as for any other type of node. Note that normalization can affect equality; to avoid this, nodes should be normalized before being compared.
      For two DocumentType nodes to be equal, the following conditions must also be satisfied: The following string attributes are equal: publicId, systemId, internalSubset.The entities NamedNodeMaps are equal.The notations NamedNodeMaps are equal.
      On the other hand, the following do not affect equality: the ownerDocument attribute, the specified attribute for Attr nodes, the isWhitespaceInElementContent attribute for Text nodes, as well as any user data or event listeners registered on the nodes. DOM Level 3 WD- Experimental. Override inherited behavior from NodeImpl to support deep equal.
      Specified by:
      isEqualNode in interface Node
      Overrides:
      isEqualNode in class NodeImpl
      Parameters:
      arg - The node to compare equality with.
      Returns:
      If the nodes, and possibly subtrees are equal, true otherwise false.
    • synchronizeChildren

      protected void synchronizeChildren()
      Override this method in subclass to hook in efficient internal data structure.
    • checkNormalizationAfterInsert

      void checkNormalizationAfterInsert(ChildNode insertedChild)
      Checks the normalized state of this node after inserting a child. If the inserted child causes this node to be unnormalized, then this node is flagged accordingly. The conditions for changing the normalized state are:
      • The inserted child is a text node and one of its adjacent siblings is also a text node.
      • The inserted child is is itself unnormalized.
      Parameters:
      insertedChild - the child node that was inserted into this node
      Throws:
      NullPointerException - if the inserted child is null
    • checkNormalizationAfterRemove

      void checkNormalizationAfterRemove(ChildNode previousSibling)
      Checks the normalized of this node after removing a child. If the removed child causes this node to be unnormalized, then this node is flagged accordingly. The conditions for changing the normalized state are:
      • The removed child had two adjacent siblings that were text nodes.
      Parameters:
      previousSibling - the previous sibling of the removed child, or null