/**
* Method get returns a new Tuple populated with only those values whose field names are specified
* in the given selector. The declarator Fields instance declares the fields and positions in the
* current Tuple instance.
*
* @param declarator of type Fields
* @param selector of type Fields
* @return Tuple
*/
public Tuple get(Fields declarator, Fields selector) {
if (!declarator.isUnknown() && elements.size() != declarator.size())
throw new TupleException(
"field declaration: " + declarator.print() + ", does not match tuple: " + print());
return get(declarator.getPos(selector, size()));
}
@Override
public Fields serialize(final Object o) {
if (!set.contains(o.getClass())) throw new IllegalArgumentException();
final Fields f = new Fields();
if (o instanceof Collection) {
final Collection<?> c = ((Collection<?>) o);
f.putObject("values", c.toArray());
} else if (o instanceof Map) {
final Map<?, ?> m = ((Map<?, ?>) o);
f.putObject("keys", m.keySet().toArray());
f.putObject("values", m.values().toArray());
}
assert f.size() > 0 : o;
return f;
}