// We should push a new StackItem lazily after updating the current stack.
StackItem newStack = null;
switch (valueType) {
case NIL:
messageUnpacker.unpackNil();
nextToken = JsonToken.VALUE_NULL;
break;
case BOOLEAN:
boolean b = messageUnpacker.unpackBoolean();
nextToken = b ? JsonToken.VALUE_TRUE : JsonToken.VALUE_FALSE;