Bug 296822 NullProgressMonitor is not thread safe for expected usage
NullProgressMonitor.setCanceled and isCanceled access the cancelled field, but there's no synchronization. The expected use is that setCanceled is called from a thread other than the one doing the work, which polls isCanceled(), so this needs to be thread safe. Could either make these two methods synchronized or make the field volatile. Should check other progress monitor implementations too.
bundles/org.eclipse.jface/src/org/eclipse/jface/wizard/ProgressMonitorPart.java
} else {
            fProgressIndicator.beginTask(totalWork);
        }
    }
    /**
     * Implements <code>IProgressMonitor.done</code>.
     * @see IProgressMonitor#done()
     */
    public void done() {
        fLabel.setText("");
        fProgressIndicator.sendRemainingWork();
        fProgressIndicator.done();
    }
    /**
     * Escapes any occurrence of '&' in the given String so that
     * it is not considered as a mnemonic
     * character in SWT ToolItems, MenuItems, Button and Labels.
     * @param in the original String
     * @return The converted String
     */
    protected static String escapeMetaCharacters(String in) {
        if (in == null || in.indexOf('&') < 0) {
			return in;
		}
        int length = in.length();
        StringBuffer out = new StringBuffer(length + 1);
        for (int i = 0; i < length; i++) {
            char c = in.charAt(i);
            if (c == '&') {
				out.append("&&");