Bug 66923 [typing]Can delete word (Ctrl-Backspace) on read only file
When you open read-only java file, all editing functions are disabled except deleting with Ctrl-Backspace and Ctrl-Del, then it is imposible to save this file. On simple text file it works ok - it blocks all edditing functions (including Ctrl-Backspace). I am using build 200406111814
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaEditor.java
/**
	 * Returns a segmentation of the given line appropriate for bidi rendering. The default
	 * implementation returns only the string literals of a java code line as segments.
	 * 
	 * @param widgetLineOffset the offset of the line
	 * @param line the content of the line
	 * @return the line's bidi segmentation
	 */
	protected int[] getBidiLineSegments(int widgetLineOffset, String line) {
		if (line != null && line.length() > 0) {
			ISourceViewer sourceViewer= getSourceViewer();
			if (sourceViewer != null) {
				int lineOffset;
				if (sourceViewer instanceof ITextViewerExtension5) {
					ITextViewerExtension5 extension= (ITextViewerExtension5) sourceViewer;
					lineOffset= extension.widgetOffset2ModelOffset(widgetLineOffset);
				} else {
					IRegion visible= sourceViewer.getVisibleRegion();
					lineOffset= visible.getOffset() + widgetLineOffset;
				}
				try {
					return getBidiLineSegments(sourceViewer, lineOffset);
				} catch (BadLocationException x) {
					
				}
			}
		}
		return null;
	}