org.apache.commons.jxpath.ri.model
Class VariablePointer

java.lang.Object
  extended by org.apache.commons.jxpath.ri.model.NodePointer
      extended by org.apache.commons.jxpath.ri.model.VariablePointer
All Implemented Interfaces:
java.io.Serializable, java.lang.Cloneable, java.lang.Comparable, Pointer

public class VariablePointer
extends NodePointer

Pointer to a context variable.

Version:
$Revision: 652884 $ $Date: 2008-05-02 15:02:00 -0500 (Fri, 02 May 2008) $
Author:
Dmitri Plotnikov
See Also:
Serialized Form

Field Summary
 
Fields inherited from class org.apache.commons.jxpath.ri.model.NodePointer
index, locale, parent, UNKNOWN_NAMESPACE, WHOLE_COLLECTION
 
Constructor Summary
VariablePointer(QName name)
          Create a new (non-actual) VariablePointer.
VariablePointer(Variables variables, QName name)
          Create a new VariablePointer.
 
Method Summary
 java.lang.String asPath()
          Returns an XPath that maps to this Pointer.
 NodeIterator attributeIterator(QName name)
          Returns a NodeIterator that iterates over all attributes of the current node matching the supplied node name (could have a wildcard).
 NodeIterator childIterator(NodeTest test, boolean reverse, NodePointer startWith)
          Returns a NodeIterator that iterates over all children or all children that match the given NodeTest, starting with the specified one.
 int compareChildNodePointers(NodePointer pointer1, NodePointer pointer2)
          Compares two child NodePointers and returns a positive number, zero or a positive number according to the order of the pointers.
 NodePointer createChild(JXPathContext context, QName name, int index)
          Called by a child pointer when it needs to create a parent object for a non-existent collection element.
 NodePointer createChild(JXPathContext context, QName name, int index, java.lang.Object value)
          Called by a child pointer if that child needs to assign the value supplied in the createPath(context, value) call to a non-existent node.
 NodePointer createPath(JXPathContext context)
          Called by a child pointer when it needs to create a parent object.
 NodePointer createPath(JXPathContext context, java.lang.Object value)
          Called directly by JXPathContext.
 boolean equals(java.lang.Object object)
           
protected  void findVariables(JXPathContext context)
          Assimilate the Variables instance associated with the specified context.
 java.lang.Object getBaseValue()
          Returns the value represented by the pointer before indexing.
 java.lang.Object getImmediateNode()
          Returns the object the pointer points to; does not convert it to a "canonical" type.
 NodePointer getImmediateValuePointer()
           
 int getLength()
          If the pointer represents a collection (or collection element), returns the length of the collection.
 QName getName()
          Returns the name of this node.
 int hashCode()
           
 boolean isActual()
          An actual pointer points to an existing part of an object graph, even if it is null.
 boolean isCollection()
          Returns true if the value of the pointer is an array or a Collection.
 boolean isContainer()
          If true, this node is auxiliary and can only be used as an intermediate in the chain of pointers.
 boolean isLeaf()
          If true, this node does not have children
 NodeIterator namespaceIterator()
          Returns a NodeIterator that iterates over all namespaces of the value currently pointed at.
 NodePointer namespacePointer(java.lang.String name)
          Returns a NodePointer for the specified namespace.
 void remove()
          Remove the node of the object graph this pointer points to.
 void setIndex(int index)
          Set the index of this NodePointer.
 void setValue(java.lang.Object value)
          Converts the value to the required type and changes the corresponding object to that value.
 boolean testNode(NodeTest nodeTest)
          Checks if this Pointer matches the supplied NodeTest.
 
Methods inherited from class org.apache.commons.jxpath.ri.model.NodePointer
clone, compareTo, createAttribute, escape, getAbstractFactory, getDefaultNamespaceURI, getImmediateParentPointer, getIndex, getLocale, getNamespaceResolver, getNamespaceURI, getNamespaceURI, getNode, getNodeSetByKey, getNodeValue, getParent, getPointerByID, getPointerByKey, getRootNode, getValue, getValuePointer, isAttribute, isDefaultNamespace, isLanguage, isNode, isRoot, newChildNodePointer, newNodePointer, printPointerChain, setAttribute, setNamespaceResolver, toString
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

VariablePointer

public VariablePointer(Variables variables,
                       QName name)
Create a new VariablePointer.

Parameters:
variables - Variables instance
name - variable name

VariablePointer

public VariablePointer(QName name)
Create a new (non-actual) VariablePointer.

Parameters:
name - variable name
Method Detail

isContainer

public boolean isContainer()
Description copied from class: NodePointer
If true, this node is auxiliary and can only be used as an intermediate in the chain of pointers.

Overrides:
isContainer in class NodePointer
Returns:
boolean

getName

public QName getName()
Description copied from class: NodePointer
Returns the name of this node. Can be null.

Specified by:
getName in class NodePointer
Returns:
QName

getBaseValue

public java.lang.Object getBaseValue()
Description copied from class: NodePointer
Returns the value represented by the pointer before indexing. So, if the node represents an element of a collection, this method returns the collection itself.

Specified by:
getBaseValue in class NodePointer
Returns:
Object value

isLeaf

public boolean isLeaf()
Description copied from class: NodePointer
If true, this node does not have children

Specified by:
isLeaf in class NodePointer
Returns:
boolean

isCollection

public boolean isCollection()
Description copied from class: NodePointer
Returns true if the value of the pointer is an array or a Collection.

Specified by:
isCollection in class NodePointer
Returns:
boolean

getImmediateNode

public java.lang.Object getImmediateNode()
Description copied from class: NodePointer
Returns the object the pointer points to; does not convert it to a "canonical" type.

Specified by:
getImmediateNode in class NodePointer
Returns:
Object node

setValue

public void setValue(java.lang.Object value)
Description copied from class: NodePointer
Converts the value to the required type and changes the corresponding object to that value.

Specified by:
setValue in interface Pointer
Specified by:
setValue in class NodePointer
Parameters:
value - the value to set

isActual

public boolean isActual()
Description copied from class: NodePointer
An actual pointer points to an existing part of an object graph, even if it is null. A non-actual pointer represents a part that does not exist at all. For instance consider the pointer "/address/street". If both address and street are not null, the pointer is actual. If address is not null, but street is null, the pointer is still actual. If address is null, the pointer is not actual. (In JavaBeans) if address is not a property of the root bean, a Pointer for this path cannot be obtained at all - actual or otherwise.

Overrides:
isActual in class NodePointer
Returns:
boolean

setIndex

public void setIndex(int index)
Description copied from class: NodePointer
Set the index of this NodePointer.

Overrides:
setIndex in class NodePointer
Parameters:
index - int

getImmediateValuePointer

public NodePointer getImmediateValuePointer()
Overrides:
getImmediateValuePointer in class NodePointer
Returns:
NodePointer is either this or a pointer for the immediately contained value.
See Also:
NodePointer.getValuePointer()

getLength

public int getLength()
Description copied from class: NodePointer
If the pointer represents a collection (or collection element), returns the length of the collection. Otherwise returns 1 (even if the value is null).

Specified by:
getLength in class NodePointer
Returns:
int

createPath

public NodePointer createPath(JXPathContext context,
                              java.lang.Object value)
Description copied from class: NodePointer
Called directly by JXPathContext. Must create path and set value.

Overrides:
createPath in class NodePointer
Parameters:
context - the owning JXPathContext
value - the new value to set
Returns:
created NodePointer

createPath

public NodePointer createPath(JXPathContext context)
Description copied from class: NodePointer
Called by a child pointer when it needs to create a parent object. Must create an object described by this pointer and return a new pointer that properly describes the new object.

Overrides:
createPath in class NodePointer
Parameters:
context - the owning JXPathContext
Returns:
created NodePointer

createChild

public NodePointer createChild(JXPathContext context,
                               QName name,
                               int index)
Description copied from class: NodePointer
Called by a child pointer when it needs to create a parent object for a non-existent collection element. It may have to expand the collection, then create an element object and return a new pointer describing the newly created element.

Overrides:
createChild in class NodePointer
Parameters:
context - the owning JXPathCOntext
name - the QName at which a child should be created
index - child index.
Returns:
created NodePointer

createChild

public NodePointer createChild(JXPathContext context,
                               QName name,
                               int index,
                               java.lang.Object value)
Description copied from class: NodePointer
Called by a child pointer if that child needs to assign the value supplied in the createPath(context, value) call to a non-existent node. This method may have to expand the collection in order to assign the element.

Overrides:
createChild in class NodePointer
Parameters:
context - the owning JXPathCOntext
name - the QName at which a child should be created
index - child index.
value - node value to set
Returns:
created NodePointer

remove

public void remove()
Description copied from class: NodePointer
Remove the node of the object graph this pointer points to.

Overrides:
remove in class NodePointer

findVariables

protected void findVariables(JXPathContext context)
Assimilate the Variables instance associated with the specified context.

Parameters:
context - JXPathContext to search

hashCode

public int hashCode()
Overrides:
hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object object)
Overrides:
equals in class java.lang.Object

asPath

public java.lang.String asPath()
Description copied from class: NodePointer
Returns an XPath that maps to this Pointer.

Specified by:
asPath in interface Pointer
Overrides:
asPath in class NodePointer
Returns:
String xpath expression

childIterator

public NodeIterator childIterator(NodeTest test,
                                  boolean reverse,
                                  NodePointer startWith)
Description copied from class: NodePointer
Returns a NodeIterator that iterates over all children or all children that match the given NodeTest, starting with the specified one.

Overrides:
childIterator in class NodePointer
Parameters:
test - NodeTest to filter children
reverse - specified iteration direction
startWith - the NodePointer to start with
Returns:
NodeIterator

attributeIterator

public NodeIterator attributeIterator(QName name)
Description copied from class: NodePointer
Returns a NodeIterator that iterates over all attributes of the current node matching the supplied node name (could have a wildcard). May return null if the object does not support the attributes.

Overrides:
attributeIterator in class NodePointer
Parameters:
name - the attribute name to test
Returns:
NodeIterator

namespaceIterator

public NodeIterator namespaceIterator()
Description copied from class: NodePointer
Returns a NodeIterator that iterates over all namespaces of the value currently pointed at. May return null if the object does not support the namespaces.

Overrides:
namespaceIterator in class NodePointer
Returns:
NodeIterator

namespacePointer

public NodePointer namespacePointer(java.lang.String name)
Description copied from class: NodePointer
Returns a NodePointer for the specified namespace. Will return null if namespaces are not supported. Will return UNKNOWN_NAMESPACE if there is no such namespace.

Overrides:
namespacePointer in class NodePointer
Parameters:
name - incoming namespace
Returns:
NodePointer for namespace

testNode

public boolean testNode(NodeTest nodeTest)
Description copied from class: NodePointer
Checks if this Pointer matches the supplied NodeTest.

Overrides:
testNode in class NodePointer
Parameters:
nodeTest - the NodeTest to execute
Returns:
true if a match

compareChildNodePointers

public int compareChildNodePointers(NodePointer pointer1,
                                    NodePointer pointer2)
Description copied from class: NodePointer
Compares two child NodePointers and returns a positive number, zero or a positive number according to the order of the pointers.

Specified by:
compareChildNodePointers in class NodePointer
Parameters:
pointer1 - first pointer to be compared
pointer2 - second pointer to be compared
Returns:
int per Java comparison conventions


Copyright © 2001-2011 Apache Software Foundation. All Rights Reserved.