public MutableSet<Entry<K, V>> entrySet() {
synchronized (this.lock) {
return SynchronizedMutableSet.of(this.getSortedMap().entrySet(), this.lock);
}
}
public MutableSet<K> keySet() {
synchronized (this.lock) {
return SynchronizedMutableSet.of(this.getSortedMap().keySet(), this.lock);
}
}
/**
* Implementation of {@link reactor.data.core.state.StateMachine} that uses an {@link
* reactor.core.Observable} to notify states of new values.
*
* @author Jon Brisbin
*/
public class ObservableStateMachine<T> implements StateMachine<T> {
private final MutableSet<Object> states = SynchronizedMutableSet.of(UnifiedSet.newSet());
private final MutableMultimap<Object, Tuple2<?, Predicate<T>>> transitions =
SynchronizedPutFastListMultimap.newMultimap();
private final boolean strict;
private final Observable observable;
/**
* Create an new {@code ObservableStateMachine} using the given {@link reactor.core.Observable}
* and denoting whether this {@link reactor.data.core.state.StateMachine} should operate in strict
* mode.
*
* @param observable {@code Observable} to use
* @param strict whether or not to operate in strict mode
* @see {@link StateMachine#strict()}
*/
public ObservableStateMachine(Observable observable, boolean strict) {
this.observable = observable;
this.strict = strict;
}
@Override
public Observable observable() {
return observable;
}
@Override
public StateMachine<T> define(Object... states) {
for (Object state : states) {
define(state);
}
return this;
}
@Override
public <V> StateMachine<T> define(V state) {
states.add(state);
return this;
}
@Override
public <V> boolean contains(V state) {
return states.contains(state);
}
@Override
public boolean strict() {
return strict;
}
@Override
public <FROM, TO> StateMachine<T> connect(FROM from, TO to) {
return connect(from, to, null);
}
@Override
public <FROM, TO> StateMachine<T> connect(FROM from, TO to, Predicate<T> predicate) {
transitions.put(from, Tuple.of(to, predicate));
return this;
}
@Override
public <FROM, TO> StateMachine<T> disconnect(FROM from, TO to) {
transitions.remove(from, to);
return this;
}
@Override
public <V, X extends Throwable> StateMachine<T> when(
Class<X> errorType, final Consumer<Tuple3<V, T, X>> errorConsumer) {
observable.on(
Selectors.type(errorType),
new Consumer<Event<Throwable>>() {
@SuppressWarnings("unchecked")
@Override
public void accept(Event<Throwable> ev) {
if (null != errorConsumer && ev.getData() instanceof StateException) {
V state = (V) ((StateException) ev.getData()).state;
X cause = (X) ev.getData().getCause();
T data = (T) ((StateException) ev.getData()).data;
errorConsumer.accept(Tuple.of(state, data, cause));
}
}
});
return this;
}
@Override
public <V> StateMachine<T> on(final V state, final Function<T, T> fn) {
if (strict) {
Assert.isTrue(states.contains(state), "State " + state + " has not been defined");
}
observable.on(
(state instanceof Selector ? (Selector) state : Selectors.object(state)),
new Consumer<Event<T>>() {
@SuppressWarnings("unchecked")
@Override
public void accept(final Event<T> data) {
try {
data.setData(fn.apply(data.getData()));
} catch (Throwable t) {
observable.notify(
t.getClass(), Event.wrap(new StateException(t, state, data.getData())));
}
}
});
return this;
}
@Override
public <V> StateMachine<T> notify(V state) {
return notify(state, null);
}
@SuppressWarnings("unchecked")
@Override
public <V> StateMachine<T> notify(final V state, final T value) {
if (strict) {
Assert.isTrue(states.contains(state), "State " + state + " has not been defined");
}
Event<T> ev = Event.wrap(value instanceof Event ? ((Event<T>) value).getData() : value);
observable.notify(
state,
ev,
new Consumer<Event<T>>() {
@Override
public void accept(final Event<T> ev) {
transition(state, ev.getData());
}
});
return this;
}
private <V> void transition(V from, final T data) {
MutableCollection<Tuple2<?, Predicate<T>>> ts = transitions.get(from);
if (ts.isEmpty()) {
return;
}
ts.forEach(
new Procedure<Tuple2<?, Predicate<T>>>() {
@SuppressWarnings("unchecked")
@Override
public void value(Tuple2<?, Predicate<T>> tup) {
if (null == tup.getT2() || tup.getT2().test(data)) {
ObservableStateMachine.this.notify(tup.getT1(), data);
}
}
});
}
private static class StateException extends Exception {
private final Object state;
private final Object data;
private StateException(Throwable cause, Object state, Object data) {
super(cause);
this.state = state;
this.data = data;
}
@Override
public String toString() {
return "StateException{" + "state=" + state + ", data=" + data + '}';
}
}
}
