WebLogic Server 8.1 API Reference: Class EntityReferenceImpl

Overview

Package

Class

Use

Tree

Deprecated

Index

Help

BEA Systems, Inc.

PREV CLASS NEXT CLASS

FRAMES NO FRAMES

SUMMARY: INNER | FIELD | CONSTR | METHOD

DETAIL: FIELD | CONSTR | METHOD

WebLogic Server 8.1 API Reference

weblogic.apache.xerces.dom
Class EntityReferenceImpl

java.lang.Object
  |
  +--weblogic.apache.xerces.dom.NodeImpl
        |
        +--weblogic.apache.xerces.dom.ChildNode
              |
              +--weblogic.apache.xerces.dom.ParentNode
                    |
                    +--weblogic.apache.xerces.dom.EntityReferenceImpl

Direct Known Subclasses:: DeferredEntityReferenceImpl

public class EntityReferenceImpl
extends ParentNode
implements org.w3c.dom.EntityReference

EntityReference models the XML &entityname; syntax, when used for entities defined by the DOM. Entities hardcoded into XML, such as character entities, should instead have been translated into text by the code which generated the DOM tree.

An XML processor has the alternative of fully expanding Entities into the normal document tree. If it does so, no EntityReference nodes will appear.

Similarly, non-validating XML processors are not required to read or process entity declarations made in the external subset or declared in external parameter entities. Hence, some applications may not make the replacement value available for Parsed Entities of these types.

EntityReference behaves as a read-only node, and the children of the EntityReference (which reflect those of the Entity, and should also be read-only) give its replacement value, if any. They are supposed to automagically stay in synch if the DocumentType is updated with new values for the Entity.

The defined behavior makes efficient storage difficult for the DOM implementor. We can't just look aside to the Entity's definition in the DocumentType since those nodes have the wrong parent (unless we can come up with a clever "imaginary parent" mechanism). We must at least appear to clone those children... which raises the issue of keeping the reference synchronized with its parent. This leads me back to the "cached image of centrally defined data" solution, much as I dislike it.

For now I have decided, since REC-DOM-Level-1-19980818 doesn't cover this in much detail, that synchronization doesn't have to be considered while the user is deep in the tree. That is, if you're looking within one of the EntityReferennce's children and the Entity changes, you won't be informed; instead, you will continue to access the same object -- which may or may not still be part of the tree. This is the same behavior that obtains elsewhere in the DOM if the subtree you're looking at is deleted from its parent, so it's acceptable here. (If it really bothers folks, we could set things up so deleted subtrees are walked and marked invalid, but that's not part of the DOM's defined behavior.)

As a result, only the EntityReference itself has to be aware of changes in the Entity. And it can take advantage of the same structure-change-monitoring code I implemented to support DeepNodeList.

See Also:: Serialized Form

Field Summary
`protected java.lang.String`	`baseURI` Base URI
`protected java.lang.String`	`name` Name of Entity referenced

Fields inherited from class weblogic.apache.xerces.dom.ParentNode

firstChild,  
fNodeListCache,  
ownerDocument

Fields inherited from class weblogic.apache.xerces.dom.ChildNode

nextSibling,  
previousSibling

Fields inherited from class weblogic.apache.xerces.dom.NodeImpl

ELEMENT_DEFINITION_NODE,  
FIRSTCHILD,  
flags,  
HASSTRING,  
IDATTRIBUTE,  
IGNORABLEWS,  
OWNED,  
ownerNode,  
READONLY,  
SPECIFIED,  
SYNCCHILDREN,  
SYNCDATA,  
TREE_POSITION_ANCESTOR,  
TREE_POSITION_DESCENDANT,  
TREE_POSITION_DISCONNECTED,  
TREE_POSITION_EQUIVALENT,  
TREE_POSITION_FOLLOWING,  
TREE_POSITION_PRECEDING,  
TREE_POSITION_SAME_NODE,  
UNNORMALIZED

Constructor Summary
`EntityReferenceImpl(CoreDocumentImpl ownerDoc, java.lang.String name)` Factory constructor.

Method Summary
`org.w3c.dom.Node`	`cloneNode(boolean deep)` Clone node.
`java.lang.String`	`getBaseURI()` DOM Level 3 WD - Experimental.
`java.lang.String`	`getNodeName()` Returns the name of the entity referenced
`short`	`getNodeType()` A short integer indicating what type of node this is.
`void`	`setBaseURI(java.lang.String uri)` NON-DOM: set base uri
`void`	`setReadOnly(boolean readOnly, boolean deep)` NON-DOM: sets the node and its children value.
`protected void`	`synchronizeChildren()` EntityReference's children are a reflection of those defined in the named Entity.

Methods inherited from class weblogic.apache.xerces.dom.ParentNode

getChildNodes, 
getChildNodesUnoptimized, 
getFirstChild, 
getLastChild, 
getLength, 
getOwnerDocument, 
getTextContent, 
hasChildNodes, 
insertBefore, 
isEqualNode, 
item, 
normalize, 
removeChild, 
replaceChild, 
setTextContent

Methods inherited from class weblogic.apache.xerces.dom.ChildNode

getNextSibling, 
getParentNode, 
getPreviousSibling

Methods inherited from class weblogic.apache.xerces.dom.NodeImpl

addEventListener, 
appendChild, 
changed, 
changes, 
compareTreePosition, 
dispatchEvent, 
getAttributes, 
getInterface, 
getLocalName, 
getNamespaceURI, 
getNodeValue, 
getPrefix, 
getReadOnly, 
getUserData, 
getUserData, 
hasAttributes, 
isDefaultNamespace, 
isSameNode, 
isSupported, 
lookupNamespacePrefix, 
lookupNamespaceURI, 
needsSyncChildren, 
removeEventListener, 
setNodeValue, 
setPrefix, 
setUserData, 
setUserData, 
synchronizeData, 
toString

Methods inherited from class java.lang.Object

clone, 
equals, 
finalize, 
getClass, 
hashCode, 
notify, 
notifyAll, 
wait, 
wait, 
wait

Field Detail

name

protected java.lang.String name

Name of Entity referenced

baseURI

protected java.lang.String baseURI

Base URI

Constructor Detail

EntityReferenceImpl

public EntityReferenceImpl(CoreDocumentImpl ownerDoc,
                           java.lang.String name)

Factory constructor.

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.

Overrides:: getNodeType in class NodeImpl

getNodeName

public java.lang.String getNodeName()

Returns the name of the entity referenced

Overrides:: getNodeName in class NodeImpl

cloneNode

public org.w3c.dom.Node cloneNode(boolean deep)

Clone node.

Overrides:: cloneNode in class ParentNode

getBaseURI

public java.lang.String getBaseURI()

DOM Level 3 WD - Experimental. Retrieve baseURI

Overrides:: getBaseURI in class NodeImpl

setBaseURI

public void setBaseURI(java.lang.String uri)

NON-DOM: set base uri

synchronizeChildren

protected void synchronizeChildren()

EntityReference's children are a reflection of those defined in the named Entity. This method creates them if they haven't been created yet. This doesn't support editing the Entity though, since this only called once for all.

Overrides:: synchronizeChildren in class ParentNode

setReadOnly

public void setReadOnly(boolean readOnly,
                        boolean deep)

NON-DOM: sets the node and its children value.

Note: make sure that entity reference and its kids could be set readonly.

Overrides:: setReadOnly in class ParentNode