set.add( ff.featureId("FID.1"));
set.add( ff.featureId("FID.2"));
Filter filter=ff.id( set );
StringWriter output = new StringWriter();
XMLHandlerHints hints=new XMLHandlerHints();
hints.put(XMLHandlerHints.FILTER_COMPLIANCE_STRICTNESS, XMLHandlerHints.VALUE_FILTER_COMPLIANCE_MEDIUM);
DocumentWriter.writeFragment(filter,
FilterSchema.getInstance(), output, hints);
String string=output.toString().replaceAll("\\s", "");
// The following test fails with Java 1.6. May be caused by some iteration order dependent code.
if (TestData.isBaseJavaPlatform()) {