javax.swing.text
Class DefaultStyledDocument.ElementBuffer

java.lang.Object
  extended by javax.swing.text.DefaultStyledDocument.ElementBuffer
All Implemented Interfaces:
Serializable
Enclosing class:
DefaultStyledDocument

public class DefaultStyledDocument.ElementBuffer
extends Object
implements Serializable

Performs all structural changes to the Element hierarchy. This class was implemented with much help from the document: http://java.sun.com/products/jfc/tsc/articles/text/element_buffer/index.html.

See Also:
Serialized Form

Constructor Summary
DefaultStyledDocument.ElementBuffer(Element root)
          Creates a new ElementBuffer for the specified root element.
 
Method Summary
 void change(int offset, int length, AbstractDocument.DefaultDocumentEvent ev)
          Modifies the element structure so that the specified interval starts and ends at an element boundary.
protected  void changeUpdate()
          Performs the actual work for change(int, int, javax.swing.text.AbstractDocument.DefaultDocumentEvent).
 Element clone(Element parent, Element clonee)
          Creates and returns a deep clone of the specified clonee with the specified parent as new parent.
 Element getRootElement()
          Returns the root element of this ElementBuffer.
 void insert(int offset, int length, DefaultStyledDocument.ElementSpec[] data, AbstractDocument.DefaultDocumentEvent ev)
          Inserts new Element in the document at the specified position.
protected  void insertUpdate(DefaultStyledDocument.ElementSpec[] data)
          Inserts new content.
 void remove(int offs, int len, AbstractDocument.DefaultDocumentEvent ev)
          Removes the content.
protected  void removeUpdate()
          Updates the element structure of the document in response to removal of content.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DefaultStyledDocument.ElementBuffer

public DefaultStyledDocument.ElementBuffer(Element root)
Creates a new ElementBuffer for the specified root element.

Parameters:
root - the root element for this ElementBuffer
Method Detail

getRootElement

public Element getRootElement()
Returns the root element of this ElementBuffer.

Returns:
the root element of this ElementBuffer

remove

public void remove(int offs,
                   int len,
                   AbstractDocument.DefaultDocumentEvent ev)
Removes the content. This method sets some internal parameters and delegates the work to removeUpdate().

Parameters:
offs - the offset from which content is remove
len - the length of the removed content
ev - the document event that records the changes

removeUpdate

protected void removeUpdate()
Updates the element structure of the document in response to removal of content. It removes the affected Elements from the document structure.


changeUpdate

protected void changeUpdate()
Performs the actual work for change(int, int, javax.swing.text.AbstractDocument.DefaultDocumentEvent). The elements at the interval boundaries are split up (if necessary) so that the interval boundaries are located at element boundaries.


change

public void change(int offset,
                   int length,
                   AbstractDocument.DefaultDocumentEvent ev)
Modifies the element structure so that the specified interval starts and ends at an element boundary. Content and paragraph elements are split and created as necessary. This also updates the DefaultDocumentEvent to reflect the structural changes. The bulk work is delegated to changeUpdate().

Parameters:
offset - the start index of the interval to be changed
length - the length of the interval to be changed
ev - the DefaultDocumentEvent describing the change

clone

public Element clone(Element parent,
                     Element clonee)
Creates and returns a deep clone of the specified clonee with the specified parent as new parent. This method can only clone direct instances of BranchElement or LeafElement.

Parameters:
parent - the new parent
clonee - the element to be cloned
Returns:
the cloned element with the new parent

insert

public void insert(int offset,
                   int length,
                   DefaultStyledDocument.ElementSpec[] data,
                   AbstractDocument.DefaultDocumentEvent ev)
Inserts new Element in the document at the specified position. Most of the work is done by insertUpdate(javax.swing.text.DefaultStyledDocument.ElementSpec[]), after some fields have been prepared for it.

Parameters:
offset - the location in the document at which the content is inserted
length - the length of the inserted content
data - the element specifications for the content to be inserted
ev - the document event that is updated to reflect the structural changes

insertUpdate

protected void insertUpdate(DefaultStyledDocument.ElementSpec[] data)
Inserts new content.

Parameters:
data - the element specifications for the elements to be inserted