NullPointer (Commons JXPath 1.3 API)

java.lang.Object
- org.apache.commons.jxpath.ri.model.NodePointer
- - org.apache.commons.jxpath.ri.model.beans.PropertyOwnerPointer
  - - org.apache.commons.jxpath.ri.model.beans.NullPointer

All Implemented Interfaces:

Serializable, Cloneable, Comparable, Pointer
```
public class NullPointer
extends PropertyOwnerPointer
```
Pointer whose value is null.

Version:

$Revision: 652915 $ $Date: 2008-05-02 23:12:57 +0200 (Fr, 02 Mai 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

Constructors
Constructor and Description
`NullPointer(Locale locale, String id)` Create a new NullPointer.
`NullPointer(NodePointer parent, QName name)` Used for the root node.
`NullPointer(QName name, Locale locale)` Create a new NullPointer.

Method Summary

Methods
Modifier and Type	Method and Description
`String`	`asPath()` Returns an XPath that maps to this Pointer.
`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, 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, Object value)` Called directly by JXPathContext.
`boolean`	`equals(Object object)`
`Object`	`getBaseValue()` Returns the value represented by the pointer before indexing.
`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.
`PropertyPointer`	`getPropertyPointer()` Get a PropertyPointer for this PropertyOwnerPointer.
`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`	`isLeaf()` If true, this node does not have children

Methods inherited from class org.apache.commons.jxpath.ri.model.beans.PropertyOwnerPointer
attributeIterator, childIterator, compareChildNodePointers, createNodeIterator, getImmediateNode, isDynamicPropertyDeclarationSupported, isValidProperty, remove, setIndex, setValue

Methods inherited from class org.apache.commons.jxpath.ri.model.NodePointer
clone, compareTo, createAttribute, escape, getAbstractFactory, getDefaultNamespaceURI, getImmediateParentPointer, getImmediateValuePointer, getIndex, getLocale, getNamespaceResolver, getNamespaceURI, getNamespaceURI, getNode, getNodeSetByKey, getNodeValue, getParent, getPointerByID, getPointerByKey, getRootNode, getValue, getValuePointer, isAttribute, isContainer, isDefaultNamespace, isLanguage, isNode, isRoot, namespaceIterator, namespacePointer, newChildNodePointer, newNodePointer, printPointerChain, setAttribute, setNamespaceResolver, testNode, toString

Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - NullPointer
```
public NullPointer(QName name,
           Locale locale)
```
    Create a new NullPointer.
    
    Parameters:
    name - node name
    locale - Locale
  - NullPointer
```
public NullPointer(NodePointer parent,
           QName name)
```
    Used for the root node.
    
    Parameters:
    parent - parent pointer
    name - node name
  - NullPointer
```
public NullPointer(Locale locale,
           String id)
```
    Create a new NullPointer.
    
    Parameters:
    locale - Locale
    id - String
- Method Detail
  - getName
```
public QName getName()
```
    Description copied from class: NodePointer
    
    Returns the name of this node. Can be null.
    
    Specified by:
    
    getName in class PropertyOwnerPointer
    
    Returns:
    QName
  - getBaseValue
```
public 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
  - 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
  - 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
  - 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
  - getPropertyPointer
```
public PropertyPointer getPropertyPointer()
```
    Description copied from class: PropertyOwnerPointer
    
    Get a PropertyPointer for this PropertyOwnerPointer.
    
    Specified by:
    
    getPropertyPointer in class PropertyOwnerPointer
    
    Returns:
    PropertyPointer
  - createPath
```
public NodePointer createPath(JXPathContext context,
                     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,
                      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
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object object)
```
    Overrides:
    
    equals in class Object
  - asPath
```
public 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
  - 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

Class NullPointer

Field Summary

Fields inherited from class org.apache.commons.jxpath.ri.model.NodePointer

Constructor Summary

Method Summary

Methods inherited from class org.apache.commons.jxpath.ri.model.beans.PropertyOwnerPointer

Methods inherited from class org.apache.commons.jxpath.ri.model.NodePointer

Methods inherited from class java.lang.Object

Constructor Detail

NullPointer

NullPointer

NullPointer

Method Detail

getName

getBaseValue

isCollection

isLeaf

isActual

getPropertyPointer

createPath

createPath

createChild

createChild

hashCode

equals

asPath

getLength