### Question:
SingleThreadJsonFactory extends JsonFactory { @Override public JsonFactory setRootValueSeparator(String sep) { if (!DefaultPrettyPrinter.DEFAULT_ROOT_VALUE_SEPARATOR.getValue().equals(sep)) { super.setRootValueSeparator(sep); jsonGenerator.setRootValueSeparator(_rootValueSeparator); } return this; } SingleThreadJsonFactory();  SingleThreadJsonFactory(SingleThreadJsonFactory factory, ObjectCodec codec); @Override JsonGenerator createGenerator(Writer w); @Override JsonGenerator createGenerator(File f, JsonEncoding enc); @Override JsonGenerator createGenerator(OutputStream out, JsonEncoding enc); @Override final JsonFactory setCharacterEscapes(CharacterEscapes esc); @Override JsonFactory setRootValueSeparator(String sep); @Override SingleThreadJsonFactory copy();  }### Answer:
@Test public void doesNotSetSeparatorBackToDefaultRootValueSeparator() { SingleThreadJsonFactory factory = new SingleThreadJsonFactory(); factory.setRootValueSeparator("#"); assertEquals("#", factory.getRootValueSeparator()); factory.setRootValueSeparator(JsonFactory.DEFAULT_ROOT_VALUE_SEPARATOR.getValue()); assertEquals("#", factory.getRootValueSeparator()); }