Class ElementImpl

  • All Implemented Interfaces:
    Serializable, Cloneable, Element, ElementTraversal, EventTarget, Node, NodeList, TypeInfo
    Direct Known Subclasses:
    DeferredElementImpl, ElementNSImpl

    public class ElementImpl
    extends ParentNode
    implements Element, ElementTraversal, TypeInfo
    Elements represent most of the "markup" and structure of the document. They contain both the data for the element itself (element name and attributes), and any contained nodes, including document text (as children).

    Elements may have Attributes associated with them; the API for this is defined in Node, but the function is implemented here. In general, XML applications should retrive Attributes as Nodes, since they may contain entity references and hence be a fairly complex sub-tree. HTML users will be dealing with simple string values, and convenience methods are provided to work in terms of Strings.

    ElementImpl does not support Namespaces. ElementNSImpl, which inherits from it, does.

    Since:
    PR-DOM-Level-1-19980818.
    Version:
    $Id$
    Author:
    Arnaud Le Hors, IBM, Joe Kesselman, IBM, Andy Clark, IBM, Ralf Pfeiffer, IBM, Michael Glavassevich, IBM
    See Also:
    ElementNSImpl, Serialized Form
    • Field Detail

      • name

        protected String name
        Element name.
    • Constructor Detail

      • ElementImpl

        protected ElementImpl()
    • Method Detail

      • getNodeType

        public short getNodeType()
        A short integer indicating what type of node this is. The named constants for this value are defined in the org.w3c.dom.Node interface.
        Specified by:
        getNodeType in interface Node
        Specified by:
        getNodeType in class NodeImpl
      • getAttributes

        public NamedNodeMap getAttributes()
        Retrieve all the Attributes as a set. Note that this API is inherited from Node rather than specified on Element; in fact only Elements will ever have Attributes, but they want to allow folks to "blindly" operate on the tree as a set of Nodes.
        Specified by:
        getAttributes in interface Node
        Overrides:
        getAttributes in class NodeImpl
        See Also:
        ElementImpl
      • cloneNode

        public Node cloneNode​(boolean deep)
        Return a duplicate copy of this Element. Note that its children will not be copied unless the "deep" flag is true, but Attributes are always replicated.
        Specified by:
        cloneNode in interface Node
        Overrides:
        cloneNode in class ParentNode
        See Also:
        Node.cloneNode(boolean)
      • getXMLBaseAttribute

        protected Attr getXMLBaseAttribute()
        NON-DOM Returns the xml:base attribute.
      • getAttribute

        public String getAttribute​(String name)
        Look up a single Attribute by name. Returns the Attribute's string value, or an empty string (NOT null!) to indicate that the name did not map to a currently defined attribute.

        Note: Attributes may contain complex node trees. This method returns the "flattened" string obtained from Attribute.getValue(). If you need the structure information, see getAttributeNode().

        Specified by:
        getAttribute in interface Element
      • getAttributeNode

        public Attr getAttributeNode​(String name)
        Look up a single Attribute by name. Returns the Attribute Node, so its complete child tree is available. This could be important in XML, where the string rendering may not be sufficient information.

        If no matching attribute is available, returns null.

        Specified by:
        getAttributeNode in interface Element
      • getElementsByTagName

        public NodeList getElementsByTagName​(String tagname)
        Returns a NodeList of all descendent nodes (children, grandchildren, and so on) which are Elements and which have the specified tag name.

        Note: NodeList is a "live" view of the DOM. Its contents will change as the DOM changes, and alterations made to the NodeList will be reflected in the DOM.

        Specified by:
        getElementsByTagName in interface Element
        Parameters:
        tagname - The type of element to gather. To obtain a list of all elements no matter what their names, use the wild-card tag name "*".
        See Also:
        DeepNodeListImpl
      • getTagName

        public String getTagName()
        Returns the name of the Element. Note that Element.nodeName() is defined to also return the tag name.

        This is case-preserving in XML. HTML should uppercasify it on the way in.

        Specified by:
        getTagName in interface Element
      • normalize

        public void normalize()
        In "normal form" (as read from a source file), there will never be two Text children in succession. But DOM users may create successive Text nodes in the course of manipulating the document. Normalize walks the sub-tree and merges adjacent Texts, as if the DOM had been written out and read back in again. This simplifies implementation of higher-level functions that may want to assume that the document is in standard form.

        To normalize a Document, normalize its top-level Element child.

        As of PR-DOM-Level-1-19980818, CDATA -- despite being a subclass of Text -- is considered "markup" and will _not_ be merged either with normal Text or with other CDATASections.

        Specified by:
        normalize in interface Node
        Overrides:
        normalize in class ParentNode
      • removeAttribute

        public void removeAttribute​(String name)
        Remove the named attribute from this Element. If the removed Attribute has a default value, it is immediately replaced thereby.

        The default logic is actually implemented in NamedNodeMapImpl. PR-DOM-Level-1-19980818 doesn't fully address the DTD, so some of this behavior is likely to change in future versions. ?????

        Note that this call "succeeds" even if no attribute by this name existed -- unlike removeAttributeNode, which will throw a not-found exception in that case.

        Specified by:
        removeAttribute in interface Element
        Throws:
        DOMException(NO_MODIFICATION_ALLOWED_ERR) - if the node is readonly.
      • removeAttributeNode

        public Attr removeAttributeNode​(Attr oldAttr)
                                 throws DOMException
        Remove the specified attribute/value pair. If the removed Attribute has a default value, it is immediately replaced.

        NOTE: Specifically removes THIS NODE -- not the node with this name, nor the node with these contents. If the specific Attribute object passed in is not stored in this Element, we throw a DOMException. If you really want to remove an attribute by name, use removeAttribute().

        Specified by:
        removeAttributeNode in interface Element
        Returns:
        the Attribute object that was removed.
        Throws:
        DOMException(NOT_FOUND_ERR) - if oldattr is not an attribute of this Element.
        DOMException(NO_MODIFICATION_ALLOWED_ERR) - if the node is readonly.
        DOMException
      • setAttribute

        public void setAttribute​(String name,
                                 String value)
        Add a new name/value pair, or replace the value of the existing attribute having that name. Note: this method supports only the simplest kind of Attribute, one whose value is a string contained in a single Text node. If you want to assert a more complex value (which XML permits, though HTML doesn't), see setAttributeNode(). The attribute is created with specified=true, meaning it's an explicit value rather than inherited from the DTD as a default. Again, setAttributeNode can be used to achieve other results.
        Specified by:
        setAttribute in interface Element
        Throws:
        DOMException(INVALID_NAME_ERR) - if the name is not acceptable. (Attribute factory will do that test for us.)
        DOMException(NO_MODIFICATION_ALLOWED_ERR) - if the node is readonly.
      • setAttributeNode

        public Attr setAttributeNode​(Attr newAttr)
                              throws DOMException
        Add a new attribute/value pair, or replace the value of the existing attribute with that name.

        This method allows you to add an Attribute that has already been constructed, and hence avoids the limitations of the simple setAttribute() call. It can handle attribute values that have arbitrarily complex tree structure -- in particular, those which had entity references mixed into their text.

        Specified by:
        setAttributeNode in interface Element
        Throws:
        DOMException(INUSE_ATTRIBUTE_ERR) - if the Attribute object has already been assigned to another Element.
        DOMException
      • getAttributeNS

        public String getAttributeNS​(String namespaceURI,
                                     String localName)
        Introduced in DOM Level 2.

        Retrieves an attribute value by local name and namespace URI.

        Specified by:
        getAttributeNS in interface Element
        Parameters:
        namespaceURI - The namespace URI of the attribute to retrieve.
        localName - The local name of the attribute to retrieve.
        Returns:
        String The Attr value as a string, or empty string if that attribute does not have a specified or default value.
        Since:
        WD-DOM-Level-2-19990923
      • setAttributeNS

        public void setAttributeNS​(String namespaceURI,
                                   String qualifiedName,
                                   String value)
        Introduced in DOM Level 2.

        Adds a new attribute. If the given namespaceURI is null or an empty string and the qualifiedName has a prefix that is "xml", the new attribute is bound to the predefined namespace "http://www.w3.org/XML/1998/namespace" [Namespaces]. If an attribute with the same local name and namespace URI is already present on the element, its prefix is changed to be the prefix part of the qualifiedName, and its value is changed to be the value parameter. This value is a simple string, it is not parsed as it is being set. So any markup (such as syntax to be recognized as an entity reference) is treated as literal text, and needs to be appropriately escaped by the implementation when it is written out. In order to assign an attribute value that contains entity references, the user must create an Attr node plus any Text and EntityReference nodes, build the appropriate subtree, and use setAttributeNodeNS or setAttributeNode to assign it as the value of an attribute.

        Specified by:
        setAttributeNS in interface Element
        Parameters:
        namespaceURI - The namespace URI of the attribute to create or alter.
        qualifiedName - The qualified name of the attribute to create or alter.
        value - The value to set in string form.
        Since:
        WD-DOM-Level-2-19990923
      • removeAttributeNS

        public void removeAttributeNS​(String namespaceURI,
                                      String localName)
        Introduced in DOM Level 2.

        Removes an attribute by local name and namespace URI. If the removed attribute has a default value it is immediately replaced. The replacing attribute has the same namespace URI and local name, as well as the original prefix.

        Specified by:
        removeAttributeNS in interface Element
        Parameters:
        namespaceURI - The namespace URI of the attribute to remove.
        localName - The local name of the attribute to remove.
        Since:
        WD-DOM-Level-2-19990923
      • getAttributeNodeNS

        public Attr getAttributeNodeNS​(String namespaceURI,
                                       String localName)
        Retrieves an Attr node by local name and namespace URI.
        Specified by:
        getAttributeNodeNS in interface Element
        Parameters:
        namespaceURI - The namespace URI of the attribute to retrieve.
        localName - The local name of the attribute to retrieve.
        Returns:
        Attr The Attr node with the specified attribute local name and namespace URI or null if there is no such attribute.
        Since:
        WD-DOM-Level-2-19990923
      • setAttributeNodeNS

        public Attr setAttributeNodeNS​(Attr newAttr)
                                throws DOMException
        Introduced in DOM Level 2.

        Adds a new attribute. If an attribute with that local name and namespace URI is already present in the element, it is replaced by the new one.

        Specified by:
        setAttributeNodeNS in interface Element
        Parameters:
        newAttr - The Attr node to add to the attribute list. When the Node has no namespaceURI, this method behaves like setAttributeNode.
        Returns:
        Attr If the newAttr attribute replaces an existing attribute with the same local name and namespace URI, the * previously existing Attr node is returned, otherwise null is returned.
        Throws:
        DOMException
        Since:
        WD-DOM-Level-2-19990923
      • setXercesAttributeNode

        protected int setXercesAttributeNode​(Attr attr)
        NON-DOM: sets attribute node for this element
      • getXercesAttribute

        protected int getXercesAttribute​(String namespaceURI,
                                         String localName)
        NON-DOM: get inded of an attribute
      • hasAttributes

        public boolean hasAttributes()
        Introduced in DOM Level 2.
        Specified by:
        hasAttributes in interface Node
        Overrides:
        hasAttributes in class NodeImpl
        Returns:
        true if this node has any attributes, false otherwise.
        See Also:
        ElementImpl
      • hasAttribute

        public boolean hasAttribute​(String name)
        Introduced in DOM Level 2.
        Specified by:
        hasAttribute in interface Element
      • hasAttributeNS

        public boolean hasAttributeNS​(String namespaceURI,
                                      String localName)
        Introduced in DOM Level 2.
        Specified by:
        hasAttributeNS in interface Element
      • getElementsByTagNameNS

        public NodeList getElementsByTagNameNS​(String namespaceURI,
                                               String localName)
        Introduced in DOM Level 2.

        Returns a NodeList of all the Elements with a given local name and namespace URI in the order in which they would be encountered in a preorder traversal of the Document tree, starting from this node.

        Specified by:
        getElementsByTagNameNS in interface Element
        Parameters:
        namespaceURI - The namespace URI of the elements to match on. The special value "*" matches all namespaces. When it is null or an empty string, this method behaves like getElementsByTagName.
        localName - The local name of the elements to match on. The special value "*" matches all local names.
        Returns:
        NodeList A new NodeList object containing all the matched Elements.
        Since:
        WD-DOM-Level-2-19990923
      • isEqualNode

        public boolean isEqualNode​(Node arg)
        DOM Level 3 WD- Experimental. Override inherited behavior from NodeImpl and ParentNode to check on attributes
        Specified by:
        isEqualNode in interface Node
        Overrides:
        isEqualNode in class ParentNode
        Parameters:
        arg - The node to compare equality with.
        Returns:
        If the nodes, and possibly subtrees are equal, true otherwise false.
      • setIdAttributeNode

        public void setIdAttributeNode​(Attr at,
                                       boolean makeId)
        DOM Level 3: register the given attribute node as an ID attribute
        Specified by:
        setIdAttributeNode in interface Element
      • setIdAttribute

        public void setIdAttribute​(String name,
                                   boolean makeId)
        DOM Level 3: register the given attribute node as an ID attribute
        Specified by:
        setIdAttribute in interface Element
      • setIdAttributeNS

        public void setIdAttributeNS​(String namespaceURI,
                                     String localName,
                                     boolean makeId)
        DOM Level 3: register the given attribute node as an ID attribute
        Specified by:
        setIdAttributeNS in interface Element
      • isDerivedFrom

        public boolean isDerivedFrom​(String typeNamespaceArg,
                                     String typeNameArg,
                                     int derivationMethod)
        Introduced in DOM Level 3.

        Checks if a type is derived from another by restriction. See: http://www.w3.org/TR/DOM-Level-3-Core/core.html#TypeInfo-isDerivedFrom

        Specified by:
        isDerivedFrom in interface TypeInfo
        Parameters:
        typeNamespaceArg - The namspace of the ancestor type declaration
        typeNameArg - The name of the ancestor type declaration
        derivationMethod - The derivation method
        Returns:
        boolean True if the type is derived by restriciton for the reference type
      • setReadOnly

        public void setReadOnly​(boolean readOnly,
                                boolean deep)
        NON-DOM: Subclassed to flip the attributes' readonly switch as well.
        Overrides:
        setReadOnly in class ParentNode
        Parameters:
        readOnly - True or false as desired.
        deep - If true, children are also toggled. Note that this will not change the state of an EntityReference or its children, which are always read-only.
        See Also:
        NodeImpl.setReadOnly(boolean, boolean)
      • synchronizeData

        protected void synchronizeData()
        Synchronizes the data (name and value) for fast nodes.
        Overrides:
        synchronizeData in class NodeImpl
      • setupDefaultAttributes

        protected void setupDefaultAttributes()
        Setup the default attributes.
      • reconcileDefaultAttributes

        protected void reconcileDefaultAttributes()
        Reconcile default attributes.
      • getDefaultAttributes

        protected NamedNodeMapImpl getDefaultAttributes()
        Get the default attributes.