de.intarsys.pdf.cos
Class COSDocumentElement

java.lang.Object
  de.intarsys.pdf.cos.COSDocumentElement

All Implemented Interfaces:

ICOSExceptionHandler

Direct Known Subclasses:

COSIndirectObject, COSObject

public abstract class COSDocumentElement
extends Object
implements ICOSExceptionHandler

This is a cos level representation of the elements that may be contained in a cos container. An element may be either a COSObject or a COSIndirectObject to a COSObject. A COSIndirectObject is never seen by an application level programmer, this is an internal construct only.

Method Summary

abstract Object	accept(ICOSObjectVisitor visitor) Accept a visitor object.
abstract COSDocumentElement	containable() The COSDocumentElement suitable for use in an ICOSContainer.
abstract COSObject	dereference() Return the real object.
abstract COSDocument	getDoc() The document where this is contained or null.
void	handleException(COSRuntimeException ex) Handle ex, optionally rethrow.
boolean	isReference() Answer true if this element is a reference (a COSIndirectObject.
boolean	isSwapped() Answer true if this elements content is swapped to a persistent store.

Methods inherited from class java.lang.Object

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

Method Detail

accept

public abstract Object accept(ICOSObjectVisitor visitor)
                       throws COSVisitorException

Accept a visitor object. The receiver selects the correct implementation in the visitor by "double dispatching".

Parameters:

visitor - The object visiting the receiver.

Returns:

Object An object depending on the visitor semantics.

Throws:

COSVisitorException - An exception depending on the visitor semantics.

containable

public abstract COSDocumentElement containable()

The COSDocumentElement suitable for use in an ICOSContainer. This may be a COSIndirectObject or the COSObject itself if not indirect.

This method should not be used by the application programmer. This is called in the COSObject lifecycle to ensure internal consistency.

dereference

public abstract COSObject dereference()

Return the real object. This is either the object itself or the object referenced by a reference object (COSIndirectObject).

Returns:

The real object.

getDoc

public abstract COSDocument getDoc()

The document where this is contained or null. A COSDocumentElement is at most contained in a single COSDocument.

Returns:

The document where this is contained.

handleException

public void handleException(COSRuntimeException ex)
                     throws COSRuntimeException

Description copied from interface: ICOSExceptionHandler

Handle ex, optionally rethrow.

Specified by:

handleException in interface ICOSExceptionHandler

Parameters:

ex - The exceptioin to be handeled.

Throws:

COSRuntimeException

isReference

public boolean isReference()

Answer true if this element is a reference (a COSIndirectObject.

Returns:

Answer true if this element is a reference.

isSwapped

public boolean isSwapped()

Answer true if this elements content is swapped to a persistent store.

Returns:

Answer true if this elements content is swapped to a persistent store.