Class ElementImpl

All Implemented Interfaces:
Cloneable, Element, EventTarget, Node, NodeList, TypeInfo
Direct Known Subclasses:
ElementNSImpl, HTMLElementImpl

public class ElementImpl extends ParentNode implements Element, 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 retrieve 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.

Author:
Arnaud Le Hors, IBM, Joe Kesselman, IBM, Andy Clark, IBM, Ralf Pfeiffer, IBM, Michael Glavassevich, IBM, Ronald Brill
See Also:
  • Field Details

    • name_

      protected String name_
      Element name.
    • attributes_

      protected AttributeMap attributes_
      Attributes.
  • Constructor Details

    • ElementImpl

      public ElementImpl(CoreDocumentImpl ownerDoc, String name)
      Constructs a default ElementImpl instance.
      Parameters:
      ownerDoc - the owner document
      name - the element name
  • Method Details

    • 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. 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
    • getNodeName

      public String getNodeName()
      Returns the name of this node. Returns the element name.
      Specified by:
      getNodeName in interface Node
      Specified by:
      getNodeName 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
    • 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.

      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
      Parameters:
      deep - whether to recursively clone all children in the subtree
      Returns:
      the cloned node
      See Also:
    • getBaseURI

      public String getBaseURI()
      DOM Level 3 WD - Experimental. Retrieve baseURI.
      Specified by:
      getBaseURI in interface Node
      Overrides:
      getBaseURI in class NodeImpl
    • getXMLBaseAttribute

      protected Attr getXMLBaseAttribute()
    • setOwnerDocument

      protected void setOwnerDocument(CoreDocumentImpl doc)
      Description copied from class: ParentNode
      NON-DOM set the ownerDocument of this node and its children
      Overrides:
      setOwnerDocument in class ParentNode
    • 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
      Returns:
      a NodeList containing all the matched Elements
      See Also:
    • 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
    • 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
    • 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
    • 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
      Parameters:
      name - the name of the attribute
      value - the value of the attribute
      Throws:
      DOMException - INVALID_NAME_ERR if the name is not acceptable
    • 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
      Parameters:
      newAttr - the attribute node to set
      Returns:
      the replaced attribute node, or null
      Throws:
      DOMException - INUSE_ATTRIBUTE_ERR if the Attribute object has already been assigned to another Element
    • 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:
      the Attr value as a string, or empty string if not specified or defaulted
    • 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". 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
    • 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.

      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
    • 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:
      the Attr node with the specified attribute local name and namespace URI, or null
    • 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
      Returns:
      the previously existing Attr node if replaced, or null otherwise
      Throws:
      DOMException - WRONG_DOCUMENT_ERR if newAttr was created from a different document
      DOMException - INUSE_ATTRIBUTE_ERR if newAttr is already an attribute of another Element
    • hasAttributes

      public boolean hasAttributes()
      Introduced in DOM Level 2.
      Specified by:
      hasAttributes in interface Node
      Overrides:
      hasAttributes in class NodeImpl
    • 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 preorder traversal order 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.
    • isEqualNode

      public boolean isEqualNode(Node arg)
      DOM Level 3 WD- Experimental. Override inherited behavior from NodeImpl to support deep equal. 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
    • 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
    • getTypeName

      public String getTypeName()
      Specified by:
      getTypeName in interface TypeInfo
      See Also:
    • getTypeNamespace

      public String getTypeNamespace()
      Specified by:
      getTypeNamespace in interface TypeInfo
      See Also:
    • 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 namespace of the ancestor type declaration
      typeNameArg - the name of the ancestor type declaration
      derivationMethod - the derivation method
      Returns:
      true if derived by restriction from the reference type, false otherwise
    • getSchemaTypeInfo

      public TypeInfo getSchemaTypeInfo()
      Method getSchemaTypeInfo.
      Specified by:
      getSchemaTypeInfo in interface Element
      Returns:
      TypeInfo