Release 2.0.0-RC4

Author: akarnokd

CHANGES.md

@@ -2,6 +2,52 @@
 
 Version 1.x can be found at https://github.com/ReactiveX/RxJava/blob/1.x/CHANGES.md
 
+### Version 2.0.0-RC4 - October 7, 2016 ([Maven](http://search.maven.org/#artifactdetails%7Cio.reactivex.rxjava2%7Crxjava%7C2.0.0-RC4%7C))
+
+This release contains new operators, further cleanups, better test coverage and bugfixes. Thanks to the respective contributors and @JakeWharton for the reviews.
+
+**API enhancements**
+
+  - [Pull 4589](https://github.com/ReactiveX/RxJava/pull/4589): Add `singleOrError`, `firstOrError`, `lastOrError` & `elementAtOrError` to `Observable` and `Flowable`
+  - [Pull 4616](https://github.com/ReactiveX/RxJava/pull/4616): Add `Completable.andThen(MaybeSource)`
+  - [Pull 4614](https://github.com/ReactiveX/RxJava/pull/4614): Add `Maybe.flatMapSingle`
+  - [Pull 4617](https://github.com/ReactiveX/RxJava/pull/4617): Add `Single.flatMapMaybe`
+  - [Pull 4585](https://github.com/ReactiveX/RxJava/pull/4585): Evaluate `Schedulers` initialization via `Callable`
+  - [Pull 4607](https://github.com/ReactiveX/RxJava/pull/4607): `TestSubscriber` & `TestObserver` add `assertValue(Predicate)`.
+  - [Pull 4627](https://github.com/ReactiveX/RxJava/pull/4627): Use predicates in `BaseTestConsumer.assertError(Class/Throwable)` to remove duplicate code, tests tweaks to remove few IDE warnings
+  - [Pull 4629](https://github.com/ReactiveX/RxJava/pull/4629): Add `Completable.fromRunnable()`
+  - [Pull 4631](https://github.com/ReactiveX/RxJava/pull/4631): `TestConsumer` don't wrap with `CompositeException` when there is only one error
+  - [Pull 4604](https://github.com/ReactiveX/RxJava/pull/4604): add `flattenAs{Observable,Flowable}` to `Single` and `Maybe`
+  - [Pull 4658](https://github.com/ReactiveX/RxJava/pull/4658): `Observable.compose` to use `ObservableTransformer`.
+  - [Pull 4667](https://github.com/ReactiveX/RxJava/pull/4667): Add `flatMap{Completable, Maybe, Single}` operators to `Flowable` and `Observable`.
+  - [Pull 4672](https://github.com/ReactiveX/RxJava/pull/4672): Remove `Function` from transformer interfaces to allow a single obj.
+  - `Maybe.ignoreElement` to return `Completable`.
+
+**Performance enhancements**
+
+  - [Pull 4612](https://github.com/ReactiveX/RxJava/pull/4612): Improve performance of `Observable.flatMapIterable`
+  - [Pull 4622](https://github.com/ReactiveX/RxJava/pull/4622): Enable operator fusion in `onBackpressureBuffer`
+
+**Bugfixes**
+
+  - [Pull 4590](https://github.com/ReactiveX/RxJava/pull/4590): Report errors from `onError` to Plugin when done.
+  - [Pull 4592](https://github.com/ReactiveX/RxJava/pull/4592): `UnicastSubject` fix `onTerminate`
+  - [Pull 4593](https://github.com/ReactiveX/RxJava/pull/4593): Enhance NPE messages
+  - [Pull 4603](https://github.com/ReactiveX/RxJava/pull/4603): RxJavaPlugins - Don't pass null throwable down to Error Handler
+  - [Pull 4619](https://github.com/ReactiveX/RxJava/pull/4619): Make `CompositeExcepetion` thread-safe like 1.x and also fix some issues.
+  - [Pull 4645](https://github.com/ReactiveX/RxJava/pull/4645): Signal NPE `ObservableAmb` `FlowableAmb`
+  - [Pull 4651](https://github.com/ReactiveX/RxJava/pull/4651): Switch `Maybe` and `Single` to use their `Transformer`s in `compose()`.
+  - [Pull 4654](https://github.com/ReactiveX/RxJava/pull/4654): Upcast `ConcurrentHashMap` to `Map` to avoid compatibility issue.
+
+
+**Removals**
+
+  - [Pull 4595](https://github.com/ReactiveX/RxJava/pull/4595): Remove `takeFirst(predicate)` from `Observable` & `Flowable`
+
+**Other**
+
+  - [Pull 4647](https://github.com/ReactiveX/RxJava/pull/4647): Merge `AmbArray` and `AmbIterable` into `Amb` for `Single`, `Maybe` and `Completable` types.
+
 ### Version 2.0.0-RC3 - September 23, 2016 ([Maven](http://search.maven.org/#artifactdetails%7Cio.reactivex.rxjava2%7Crxjava%7C2.0.0-RC3%7C))
 
 This Release Candidate features mostly internal cleanups of code and Javadoc, Reactive-Streams Test Compatibility Kit implementations (and thus verification) of our `Flowable` implementation and additional unit-test coverage. Big tanks to @vanniktech for the many contributions and @JakeWharton for the continued reviews.

README.md

@@ -30,7 +30,7 @@ The release plan for 2.x is as [follows](https://github.com/ReactiveX/RxJava/iss
   - **25/08/2016: Release Candidate 1: stabilized API and feature set**
   - **05/09/2016: Release Candidate 2: addressing feedback from RC 1**
   - **23/09/2016: Release Candidate 3: addressing feedback from RC 2**
-  - 07/10/2016: Release Candidate 4: addressing feedback from RC 3
+  - **07/10/2016: Release Candidate 4: addressing feedback from RC 3**
   - 21/10/2016: Release Candidate 5: addressing feedback from RC 4
   - 29/10/2016: Stable Release: General availability