Promise`1.cs
159 lines
| 3.9 KiB
| text/x-csharp
|
CSharpLexer
/ Implab / Promise`1.cs
cin
|
r248 | using System; | ||
| using System.Diagnostics; | ||||
| using System.Reflection; | ||||
| using Implab.Parallels; | ||||
| namespace Implab { | ||||
| public class Promise<T> : AbstractEvent<IResolvable<T>>, IPromise<T> { | ||||
| class ResolvableSignal : IResolvable<T> { | ||||
| public Signal Signal { get; private set; } | ||||
| public ResolvableSignal() { | ||||
| Signal = new Signal(); | ||||
| } | ||||
| public void Reject(Exception error) { | ||||
| Signal.Set(); | ||||
| } | ||||
| public void Resolve(T result) { | ||||
| Signal.Set(); | ||||
| } | ||||
| } | ||||
| class ResolvableWrapper : IResolvable<T> { | ||||
| readonly IResolvable m_resolvable; | ||||
| public ResolvableWrapper(IResolvable resolvable) { | ||||
| m_resolvable = resolvable; | ||||
| } | ||||
| public void Reject(Exception reason) { | ||||
| m_resolvable.Reject(reason); | ||||
| } | ||||
| public void Resolve(T value) { | ||||
| m_resolvable.Resolve(); | ||||
| } | ||||
| } | ||||
| PromiseState m_state; | ||||
| T m_result; | ||||
| Exception m_error; | ||||
| public bool IsRejected { | ||||
| get { | ||||
| return m_state == PromiseState.Rejected; | ||||
| } | ||||
| } | ||||
| public bool IsFulfilled { | ||||
| get { | ||||
| return m_state == PromiseState.Fulfilled; | ||||
| } | ||||
| } | ||||
| public Exception RejectReason { | ||||
| get { | ||||
| return m_error; | ||||
| } | ||||
| } | ||||
| internal void ResolvePromise(T result) { | ||||
| if (BeginTransit()) { | ||||
| m_result = result; | ||||
| m_state = PromiseState.Fulfilled; | ||||
| CompleteTransit(); | ||||
| } | ||||
| } | ||||
| internal void RejectPromise(Exception reason) { | ||||
| if (BeginTransit()) { | ||||
| m_error = reason; | ||||
| m_state = PromiseState.Rejected; | ||||
| CompleteTransit(); | ||||
| } | ||||
| } | ||||
| #region implemented abstract members of AbstractPromise | ||||
| protected override void SignalHandler(IResolvable<T> handler) { | ||||
| switch (m_state) { | ||||
| case PromiseState.Fulfilled: | ||||
| handler.Resolve(m_result); | ||||
| break; | ||||
| case PromiseState.Rejected: | ||||
| handler.Reject(RejectReason); | ||||
| break; | ||||
| default: | ||||
| throw new InvalidOperationException(String.Format("Invalid promise signal: {0}", m_state)); | ||||
| } | ||||
| } | ||||
| protected void WaitResult(int timeout) { | ||||
| if (!(IsResolved || GetFulfillSignal().Wait(timeout))) | ||||
| throw new TimeoutException(); | ||||
| } | ||||
| protected Signal GetFulfillSignal() { | ||||
| var next = new ResolvableSignal(); | ||||
| Then(next); | ||||
| return next.Signal; | ||||
| } | ||||
| #endregion | ||||
| public Type ResultType { | ||||
| get { | ||||
| return typeof(void); | ||||
| } | ||||
| } | ||||
| protected void Rethrow() { | ||||
| if (m_error is OperationCanceledException) | ||||
| throw new OperationCanceledException("Operation cancelled", m_error); | ||||
| else | ||||
| throw new TargetInvocationException(m_error); | ||||
| } | ||||
| public void Then(IResolvable<T> next) { | ||||
| AddHandler(next); | ||||
| } | ||||
| public void Then(IResolvable next) { | ||||
| AddHandler(new ResolvableWrapper(next)); | ||||
| } | ||||
| public IPromise<T2> Cast<T2>() { | ||||
| return (IPromise<T2>)this; | ||||
| } | ||||
| void IPromise.Join() { | ||||
| Join(); | ||||
| } | ||||
| void IPromise.Join(int timeout) { | ||||
| Join(timeout); | ||||
| } | ||||
| public T Join() { | ||||
| WaitResult(-1); | ||||
| if (IsRejected) | ||||
| Rethrow(); | ||||
| return m_result; | ||||
| } | ||||
| public T Join(int timeout) { | ||||
| WaitResult(timeout); | ||||
| if (IsRejected) | ||||
| Rethrow(); | ||||
| return m_result; | ||||
| } | ||||
| } | ||||
| } | ||||