de.ispsoft.jaxme
Class ObservedHandlerImpl

java.lang.Object
  de.ispsoft.jaxme.ObservedHandlerImpl

All Implemented Interfaces:

org.xml.sax.ContentHandler, ObservedHandler

Direct Known Subclasses:

JMAtomicContentHandler, JMContentHandler

public abstract class ObservedHandlerImpl

extends java.lang.Object

implements ObservedHandler

A default implementation for an ObservedHandler.

Author:

Jochen Wiedmann

Field Summary

protected java.lang.String	context
protected int	level
protected org.xml.sax.Locator	locator
protected Observer	observer
protected java.util.Collection	resultCollection
protected java.lang.Object	resultNode

Constructor Summary

ObservedHandlerImpl()
Creates a new instance of ObservedHandlerImpl.

Method Summary

protected void	addResultNode(java.lang.Object o) Sets a result node, the result of calling getResultNode().
void	endDocument() Called to terminate the document.
java.lang.String	getContext() Returns the context to use in error messages.
java.lang.String	getContext(java.lang.String pName) Returns the context to use in error messages, extended by the given element or attribute name.
Observer	getObserver() Returns a possible observer.
java.util.Collection	getResultCollection() Returns a collection where to add successfully parsed elements, Strings or other JMNode instances.
java.lang.Object	getResultNode() This method may be called after a startDocument(), ..., endDocument() sequence.
protected org.xml.sax.SAXException	getSAXException(java.lang.String msg) Depending on the presence of a locator, returns a SAXException or a SAXParseException.
protected org.xml.sax.SAXException	getSAXException(java.lang.String msg, java.lang.Exception e) Depending on the presence of a locator, returns a SAXException or a SAXParseException.
void	setContext(java.lang.String pContext) Sets a context to use in error messages.
void	setDocumentLocator(org.xml.sax.Locator pLocator) Sets a document locator.
void	setObserver(Observer pObserver) Sets a possible observer.
void	setResultCollection(java.util.Collection pCollection) Sets a collection where to add successfully parsed elements, Strings or other JMNode instances.
void	startDocument() This method is for resetting the ObservedHandlerImpl.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.xml.sax.ContentHandler

characters, endElement, endPrefixMapping, ignorableWhitespace, processingInstruction, skippedEntity, startElement, startPrefixMapping

Field Detail

resultNode

protected java.lang.Object resultNode

resultCollection

protected java.util.Collection resultCollection

observer

protected Observer observer

locator

protected org.xml.sax.Locator locator

context

protected java.lang.String context

level

protected int level

Constructor Detail

ObservedHandlerImpl

public ObservedHandlerImpl()

Creates a new instance of ObservedHandlerImpl.

Method Detail

getObserver

public Observer getObserver()

Returns a possible observer. If the observer is non-null, then it will be notified for any element, String or JMNode that has been read successfully.

Specified by:

getObserver in interface ObservedHandler

See Also:

setObserver(de.ispsoft.jaxme.Observer)

setObserver

public void setObserver(Observer pObserver)

Sets a possible observer. If the observer is non-null, then it will be notified for any element, String or JMNode that has been read successfully. The parsed element can be accessed as follows:

  public void notify(Object o) {
    ObservedHandler handler = (ObservedHandler) o;
    Object o = handler.getResultNode();
    if (o instanceof JMAnyElement) {
      JMAnyElement element = (JMAnyElement) o;
      ... // Do something here
    } else {
      ... // Other possibilities: String, JMPI, JMEntity
    }
  }
 

Specified by:

setObserver in interface ObservedHandler

Parameters:

pObserver - The observer being notified or null to disable notification.

See Also:

getObserver()

getResultNode

public java.lang.Object getResultNode()

This method may be called after a startDocument(), ..., endDocument() sequence. It returns the result object, which may be either of

• a String
• a JMAnyElement
• a JMPI
• a JMEntity

Specified by:

getResultNode in interface ObservedHandler

setResultCollection

public void setResultCollection(java.util.Collection pCollection)

Sets a collection where to add successfully parsed elements, Strings or other JMNode instances. The collection can be processed if the parsing is done completely.

This collection is relevant only, if you expect to parse multiple documents in a sequence. For example, you might read a SOAP reply where the actual result consists of a single root node and a lot of childs.

If you expect a single result element only, you might prefer using the getResultNode() method.

The collection can be processed as follows:

   for (java.util.Iterator iter = handler.getResultCollection();
        iter.hasNext();  ) {
     Object o = iter.next();
     if (o instanceof JMAnyElement) {
       JMAnyElement element = (JMAnyElement) o;
       ... // Do something here
     } else {
       ... // Other possibilities: String, JMPI or JMEntity
     }
   }
 

Specified by:

setResultCollection in interface ObservedHandler

See Also:

getResultCollection()

getResultCollection

public java.util.Collection getResultCollection()

Returns a collection where to add successfully parsed elements, Strings or other JMNode instances. The collection can be processed if the parsing is done completely.

This collection is relevant only, if you expect to parse multiple documents in a sequence. For example, you might read a SOAP reply where the actual result consists of a single root node and a lot of childs.

If you expect a single result element only, you might prefer using the getResultNode() method.

Specified by:

getResultCollection in interface ObservedHandler

See Also:

setResultCollection(java.util.Collection)

addResultNode

protected void addResultNode(java.lang.Object o)
                      throws org.xml.sax.SAXException

Sets a result node, the result of calling getResultNode(). If the result collection is non-null, then the result node will be added to the collection. If the observer is non-null, then it will be notified.

Throws:

org.xml.sax.SAXException

setDocumentLocator

public void setDocumentLocator(org.xml.sax.Locator pLocator)

Sets a document locator.

Specified by:

setDocumentLocator in interface org.xml.sax.ContentHandler

getSAXException

protected org.xml.sax.SAXException getSAXException(java.lang.String msg)

Depending on the presence of a locator, returns a SAXException or a SAXParseException.

getSAXException

protected org.xml.sax.SAXException getSAXException(java.lang.String msg,
                                                   java.lang.Exception e)

Depending on the presence of a locator, returns a SAXException or a SAXParseException.

startDocument

public void startDocument()
                   throws org.xml.sax.SAXException

This method is for resetting the ObservedHandlerImpl. Concrete subclasses should call this from within their own startDocument() methods.

Specified by:

startDocument in interface org.xml.sax.ContentHandler

Throws:

org.xml.sax.SAXException

endDocument

public void endDocument()
                 throws org.xml.sax.SAXException

Called to terminate the document. Does nothing.

Specified by:

endDocument in interface org.xml.sax.ContentHandler

Throws:

org.xml.sax.SAXException

setContext

public void setContext(java.lang.String pContext)

Sets a context to use in error messages.

Specified by:

setContext in interface ObservedHandler

Parameters:

pContext - or null for top level elements.

getContext

public java.lang.String getContext()

Returns the context to use in error messages.

Specified by:

getContext in interface ObservedHandler

Returns:

Current context or null for top level elements.

getContext

public java.lang.String getContext(java.lang.String pName)

Returns the context to use in error messages, extended by the given element or attribute name.

Example:

  String context = "/Address/Name";
  setContext(context);
  getContext("FirstName");  // Returns "/Address/Name/FirstName"
 

Specified by:

getContext in interface ObservedHandler