Bug 96917 [implementation] If two editors use the 2.x-compatible API, one or both doesn't work
At least one problem is that 3.0 installs partitioners for every editor that might possibly edit a file, but each editor expects its own partitioner to be installed. Leading to the famous white screen with blue line.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/DocumentAdapter.java
}
		fReplaceCmd.replace(fDocument.getLength(), 0, text);
	}
	/*
	 * @see IBuffer#close()
	 */
	public void close() {
		if (isClosed())
			return;
		IDocument d= fDocument;
		fDocument= null;
		d.removePrenotifiedDocumentListener(this);
		if (fTextFileBuffer != null) {
			ITextFileBufferManager manager= FileBuffers.getTextFileBufferManager();
			try {
				manager.disconnect(fTextFileBuffer.getLocation(), new NullProgressMonitor());
			} catch (CoreException x) {
				
			}
			fTextFileBuffer= null;
		}
		fireBufferChanged(new BufferChangedEvent(this, 0, 0, null));
		fBufferListeners.clear();
	}
	/*
	 * @see IBuffer#getChar(int)
	 */
	public char getChar(int position) {
		try {
			return fDocument.getChar(position);