org.apache.struts2.views.xslt

Class AdapterFactory

java.lang.Object

org.apache.struts2.views.xslt.AdapterFactory

public class AdapterFactory
extends Object

AdapterFactory produces Node adapters for Java object types. Adapter classes are generally instantiated dynamically via a no-args constructor and populated with their context information via the AdapterNode interface.

This factory supports proxying of generic DOM Node trees, allowing arbitrary Node types to be mixed together. You may simply return a Document or Node type as an object property and it will appear as a sub-tree in the XML as you'd expect. See #proxyNode().

Customization of the result XML can be accomplished by providing alternate adapters for Java types. Adapters are associated with Java types through the registerAdapterType() method.

For example, since there is no default Date adapter, Date objects will be rendered with the generic Bean introspecting adapter, producing output like:

     <date>
      <date>19</date>
      <day>1</day>
      <hours>0</hours>
      <minutes>7</minutes>
      <month>8</month>
      <seconds>4</seconds>
      <time>1127106424531</time>
      <timezoneOffset>300</timezoneOffset>
      <year>105</year>
     </date>
 

By extending the StringAdapter and overriding its normal behavior we can create a custom Date formatter:

     public static class CustomDateAdapter extends StringAdapter {
       protected String getStringValue() {
           Date date = (Date)getPropertyValue();
           return DateFormat.getTimeInstance( DateFormat.FULL ).format( date );
       }
   }
 

Producing output like:

    <date>12:02:54 AM CDT</date>
 

The StringAdapter (which is normally invoked only to adapt String values) is a useful base for these kinds of customizations and can produce structured XML output as well as plain text by setting its parseStringAsXML() property to true.

See provided examples.

Constructor Summary

Constructors

Constructor and Description
AdapterFactory()

Method Summary

Modifier and Type	Method and Description
Document	adaptDocument(String propertyName, Object propertyValue) Create a top level Document adapter for the specified Java object.
Node	adaptNode(AdapterNode parent, String propertyName, Object value) Create an Node adapter for a child element.
Node	adaptNullValue(AdapterNode parent, String propertyName) Create an appropriate adapter for a null value.
Class	getAdapterForValue(Object value)
NamedNodeMap	proxyNamedNodeMap(AdapterNode parent, NamedNodeMap nnm)
Node	proxyNode(AdapterNode parent, Node node) Construct a proxy adapter for a value that is an existing DOM Node.
void	registerAdapterType(Class type, Class adapterType) Register an adapter type for a Java class type.

Methods inherited from class java.lang.Object

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

Constructor Detail

AdapterFactory

public AdapterFactory()

Method Detail

registerAdapterType

public void registerAdapterType(Class type,
                                Class adapterType)

Register an adapter type for a Java class type.

Parameters:

type - the Java class type which is to be handled by the adapter.

adapterType - The adapter class, which implements AdapterNode.

adaptDocument

public Document adaptDocument(String propertyName,
                              Object propertyValue)
                       throws IllegalAccessException,
                              InstantiationException

Create a top level Document adapter for the specified Java object. The document will have a root element with the specified property name and contain the specified Java object content.

Parameters:

propertyName - the name of the root document element

propertyValue - the property value

Returns:

the document object

Throws:

IllegalAccessException - in case of illegal access

InstantiationException - in case of instantiation errors

adaptNode

public Node adaptNode(AdapterNode parent,
                      String propertyName,
                      Object value)

Create an Node adapter for a child element. Note that the parent of the created node must be an AdapterNode, however the child node itself may be any type of Node.

Parameters:

parent - the parent adapter node

propertyName - the name of th property

value - the value

Returns:

a node

See Also:

adaptDocument( String, Object )

proxyNode

public Node proxyNode(AdapterNode parent,
                      Node node)

Construct a proxy adapter for a value that is an existing DOM Node. This allows arbitrary DOM Node trees to be mixed in with our results. The proxied nodes are read-only and currently support only limited types of Nodes including Element, Text, and Attributes. (Other Node types may be ignored by the proxy and not appear in the result tree).

// TODO: NameSpaces are not yet supported.

This method is primarily for use by the adapter node classes.

Parameters:

parent - parent adapter node

node - node

Returns:

proxy node

proxyNamedNodeMap

public NamedNodeMap proxyNamedNodeMap(AdapterNode parent,
                                      NamedNodeMap nnm)

adaptNullValue

public Node adaptNullValue(AdapterNode parent,
                           String propertyName)

Create an appropriate adapter for a null value.

Parameters:

parent - parent adapter node

propertyName - the property name

Returns:

the new node

getAdapterForValue

public Class getAdapterForValue(Object value)