JTextPane editor large file & performance

Question

Hi,
I'm using a JTextPane to edit XML files. A jflex parser split xml file in tokens and using a custom document (extends
DefaultStyledDocument) i color syntax:
doc.setCharacterAttributes(token.getCharBegin() + change,
     token.getCharEnd()     - token.getCharBegin(),
        Token_Styles_Define.getStyle(token.getDescription()),  true);My problem is to load and edit large xml file, for exemple a 400kb xml file takes 30 seconds and for 700kb 1Mb i get java heap space.
I google it and i found :
" Define a limit that JTextPane/JEditorPane can handle well (like 500KB or 1MB). You'll only need to load a chunk of the file into the control with this size.
Start by loading the 1st partition of the file.
Then you need to interact with the scroll container and see if it has reached the end/beginning of the current chunk of the file. If so, show a nice waiting cursor and load the previous/next chunk to memory and into the text control.
The loading chunk is calculated from your current cursor position in the file (offset).
loading chunk = offset - limit/2 to offset + limit/2
The text on the JTextPane/JEditorPane must not change when loading chunks or else the user feels like is in another position of the file.
This is not a trivial solution but if you don't find any other 3rd party control to do this I would go this way. " (bruno conde)
Is this a good solution and can anybody give me an exemple (link tutorial project) ? or are any other solution?
How can we improve jtextpane performance?
Thx

Answer 1

Yes, i allready done that (using SwingUtilities.invokeLater and updates are only performed on document objects that are not attached to text components at the time that the updates are made)
The slow speed of insertion in a JTextPane has at least two culprits. The first is simply an effect of the Model-View-Controller architecture: If the document into which strings are being inserted is serving as the model for a visible text pane, each insertion will trigger a re-rendering of the display, which may in turn trigger other user interface updates. For interactive editing, this is exactly the behavior that one would want, since the results of user input should be immediately visible when editing text pane content. For initializing a text pane with a large amount of content, or, in general, making large “batch” edits, the overhead of repeated UI updates is signficant.
The second source of sluggishness is an implementation detail of DefaultStyledDocument. Unlike most Swing classes, which should only be modified in the AWT thread, DefaultStyledDocument is designed to be thread-safe. This requires DefaultStyledDocument to implement locking, so that multiple threads do not try to update the document contents at the same time. This locking imposes a small amount of overhead on each insertion or other document modification, which can add up to a long delay for large and complex text insertions.
[Faster JTextPane Text Insertion|http://javatechniques.com/public/java/docs/gui/jtextpane-speed-part1.html]
but is still slow (reading file)...and the other problem is with memory usage.
I found this subject on many other forums but not with a satisfactory answer ......must be a solution
Thx for your answers guys!