### Question:
XtceAssembler { public final String toXtce(XtceDb xtceDb) { return toXtce(xtceDb, "/", fqn -> true); }  final String toXtce(XtceDb xtceDb); final String toXtce(XtceDb xtceDb, String topSpaceSystem, Predicate<String> filter);  }### Answer:
@Test public void test1() throws Exception { Map<String, Object> m1 = new HashMap<>(); m1.put("type", "xtce"); m1.put("spec", "src/test/resources/xtce/BogusSAT-2.xml"); List<YConfiguration> mdbConfigs1 = Arrays.asList(YConfiguration.wrap(m1)); XtceDb db1 = XtceDbFactory.createInstance(mdbConfigs1, false, false); String xml = new XtceAssembler().toXtce(db1); File f = File.createTempFile("test1", ".xml"); try (FileWriter fw = new FileWriter(f)) { fw.write(xml); } Map<String, Object> m2 = new HashMap<>(); m2.put("type", "xtce"); m2.put("spec", f.getAbsolutePath()); List<YConfiguration> mdbConfigs2 = Arrays.asList(YConfiguration.wrap(m2)); XtceDb db2 = XtceDbFactory.createInstance(mdbConfigs2, false, false); f.delete(); compareDatabases(db1, db2); }