Ahh lambdas :-)
Niclas Hedhman a écrit :
> Gang,
> while working on something else, an interesting pattern was "discovered",
> which I think minimizes the Factoty/Builder stuff quite a bit;
>
> public interface Amount
> {
> Property<Long> value();
> Property<Currency> currency();
> }
>
>
> @Structure
> ValueBuilderFactory vbf;
>
>
> Amount a = vbf.create( Amount.class, proto ->
> {
> proto.value().set( 100 );
> proto.currency().set( Currency.USD );
> return proto;
> } );
>
>
> And if we need to assign the private mixins;
>
> public interface Amount
> {
> interface State
> {
> Property<Long> value();
> Property<Currency> currency();
> }
> }
>
> Amount a = vbf.create( Amount.class, (proto, builder) ->
> {
> Amount.State state = builder.prototypeFor( Amount.State.class );
> state.value().set( 100 );
> state.currency().set( Currency.USD );
> return proto;
> } );
I kinda like it. But it's not that different than:
ValueBuilder<Amount> builder = vbf.newValueBuilder( Amount.class );
Amount.State state = builder.prototypeFor( Amount.State.class );
state.value().set( 100 );
state.currency().set( Currency.USD );
Amount a = builder.newInstance();
> And maybe even a prototype generator, with a Predicate
>
> Stream<Amount> s = vbf.createStream(
> Amount.class,
> proto -> proto.currency().set( Currency.USD),
> (proto, idx) -> idx < 100,
> (proto, idx) -> proto.amount().set(idx)
> );
>
> or, perhaps it should (also?) be a Supplier.
Now that could be interesting :)
What about a supplier for the sequence?
Stream<Amount> s = vbf.createStream(
Amount.class,
proto -> proto.currency().set( Currency.USD ),
() -> IntStream.range(23, 42).filter( idx -> idx & 1 == 0 ),
(proto, idx) -> proto.amount().set(idx)
);
Could also be used with infinite streams:
Stream<Amount> s = vbf.createStream(
Amount.class,
proto -> proto.currency().set( Currency.USB ),
() -> IntStream.generate( ..something infinite.. ),
(proto, step) -> proto.amount().set(step.getAmount())
).limit(100);
> A whole new world opened up, but it doesn't "feel" much like Java anymore.
Yep :)
