ua = fopFactory.newFOUserAgent();
renderer = factory.createRenderer(ua, MimeConstants.MIME_FOP_IF);
assertTrue(renderer instanceof IFRenderer);
factory.setRendererPreferred(false);
ua = fopFactory.newFOUserAgent();
overrideRenderer = new PDFRenderer();
overrideRenderer.setUserAgent(ua);
ua.setRendererOverride(overrideRenderer);
renderer = factory.createRenderer(ua, null);
assertTrue(renderer == overrideRenderer);