--- jsr166/src/test/tck/CompletableFutureTest.java 2014/06/16 20:44:14 1.85 +++ jsr166/src/test/tck/CompletableFutureTest.java 2016/06/26 16:01:17 1.149 @@ -5,35 +5,50 @@ * http://creativecommons.org/publicdomain/zero/1.0/ */ -import junit.framework.*; +import static java.util.concurrent.TimeUnit.MILLISECONDS; +import static java.util.concurrent.TimeUnit.SECONDS; +import static java.util.concurrent.CompletableFuture.completedFuture; +import static java.util.concurrent.CompletableFuture.failedFuture; + +import java.lang.reflect.Method; +import java.lang.reflect.Modifier; + +import java.util.stream.Collectors; +import java.util.stream.Stream; + +import java.util.ArrayList; +import java.util.Arrays; +import java.util.List; +import java.util.Objects; +import java.util.Set; import java.util.concurrent.Callable; -import java.util.concurrent.Executor; -import java.util.concurrent.ExecutorService; -import java.util.concurrent.Executors; import java.util.concurrent.CancellationException; -import java.util.concurrent.CountDownLatch; -import java.util.concurrent.ExecutionException; -import java.util.concurrent.Future; import java.util.concurrent.CompletableFuture; import java.util.concurrent.CompletionException; import java.util.concurrent.CompletionStage; +import java.util.concurrent.ExecutionException; +import java.util.concurrent.Executor; import java.util.concurrent.ForkJoinPool; import java.util.concurrent.ForkJoinTask; import java.util.concurrent.TimeoutException; +import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicInteger; -import static java.util.concurrent.TimeUnit.MILLISECONDS; -import static java.util.concurrent.TimeUnit.SECONDS; -import java.util.*; -import java.util.function.Supplier; -import java.util.function.Consumer; +import java.util.concurrent.atomic.AtomicReference; import java.util.function.BiConsumer; -import java.util.function.Function; import java.util.function.BiFunction; +import java.util.function.Consumer; +import java.util.function.Function; +import java.util.function.Predicate; +import java.util.function.Supplier; + +import junit.framework.AssertionFailedError; +import junit.framework.Test; +import junit.framework.TestSuite; public class CompletableFutureTest extends JSR166TestCase { public static void main(String[] args) { - junit.textui.TestRunner.run(suite()); + main(suite(), args); } public static Test suite() { return new TestSuite(CompletableFutureTest.class); @@ -44,7 +59,7 @@ public class CompletableFutureTest exten void checkIncomplete(CompletableFuture f) { assertFalse(f.isDone()); assertFalse(f.isCancelled()); - assertTrue(f.toString().contains("[Not completed]")); + assertTrue(f.toString().contains("Not completed")); try { assertNull(f.getNow(null)); } catch (Throwable fail) { threadUnexpectedException(fail); } @@ -57,9 +72,8 @@ public class CompletableFutureTest exten } void checkCompletedNormally(CompletableFuture f, T value) { - try { - assertEquals(value, f.get(LONG_DELAY_MS, MILLISECONDS)); - } catch (Throwable fail) { threadUnexpectedException(fail); } + checkTimedGet(f, value); + try { assertEquals(value, f.join()); } catch (Throwable fail) { threadUnexpectedException(fail); } @@ -75,94 +89,95 @@ public class CompletableFutureTest exten assertTrue(f.toString().contains("[Completed normally]")); } - void checkCompletedWithWrappedCFException(CompletableFuture f) { - try { - f.get(LONG_DELAY_MS, MILLISECONDS); - shouldThrow(); - } catch (ExecutionException success) { - assertTrue(success.getCause() instanceof CFException); - } catch (Throwable fail) { threadUnexpectedException(fail); } - try { - f.join(); - shouldThrow(); - } catch (CompletionException success) { - assertTrue(success.getCause() instanceof CFException); - } - try { - f.getNow(null); - shouldThrow(); - } catch (CompletionException success) { - assertTrue(success.getCause() instanceof CFException); + /** + * Returns the "raw" internal exceptional completion of f, + * without any additional wrapping with CompletionException. + */ + Throwable exceptionalCompletion(CompletableFuture f) { + // handle (and whenComplete) can distinguish between "direct" + // and "wrapped" exceptional completion + return f.handle((U u, Throwable t) -> t).join(); + } + + void checkCompletedExceptionally(CompletableFuture f, + boolean wrapped, + Consumer checker) { + Throwable cause = exceptionalCompletion(f); + if (wrapped) { + assertTrue(cause instanceof CompletionException); + cause = cause.getCause(); } - try { - f.get(); - shouldThrow(); - } catch (ExecutionException success) { - assertTrue(success.getCause() instanceof CFException); - } catch (Throwable fail) { threadUnexpectedException(fail); } - assertTrue(f.isDone()); - assertFalse(f.isCancelled()); - assertTrue(f.toString().contains("[Completed exceptionally]")); - } + checker.accept(cause); - void checkCompletedExceptionallyWithRootCause(CompletableFuture f, - Throwable ex) { + long startTime = System.nanoTime(); try { f.get(LONG_DELAY_MS, MILLISECONDS); shouldThrow(); } catch (ExecutionException success) { - assertSame(ex, success.getCause()); + assertSame(cause, success.getCause()); } catch (Throwable fail) { threadUnexpectedException(fail); } + assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS / 2); + try { f.join(); shouldThrow(); } catch (CompletionException success) { - assertSame(ex, success.getCause()); - } + assertSame(cause, success.getCause()); + } catch (Throwable fail) { threadUnexpectedException(fail); } + try { f.getNow(null); shouldThrow(); } catch (CompletionException success) { - assertSame(ex, success.getCause()); - } + assertSame(cause, success.getCause()); + } catch (Throwable fail) { threadUnexpectedException(fail); } + try { f.get(); shouldThrow(); } catch (ExecutionException success) { - assertSame(ex, success.getCause()); + assertSame(cause, success.getCause()); } catch (Throwable fail) { threadUnexpectedException(fail); } - assertTrue(f.isDone()); assertFalse(f.isCancelled()); + assertTrue(f.isDone()); + assertTrue(f.isCompletedExceptionally()); assertTrue(f.toString().contains("[Completed exceptionally]")); } - void checkCompletedWithWrappedException(CompletableFuture f, - Throwable ex) { - checkCompletedExceptionallyWithRootCause(f, ex); - try { - CompletableFuture spy = f.handle - ((U u, Throwable t) -> t); - assertTrue(spy.join() instanceof CompletionException); - assertSame(ex, spy.join().getCause()); - } catch (Throwable fail) { threadUnexpectedException(fail); } + void checkCompletedWithWrappedCFException(CompletableFuture f) { + checkCompletedExceptionally(f, true, + (t) -> assertTrue(t instanceof CFException)); } - void checkCompletedExceptionally(CompletableFuture f, Throwable ex) { - checkCompletedExceptionallyWithRootCause(f, ex); - try { - CompletableFuture spy = f.handle - ((U u, Throwable t) -> t); - assertSame(ex, spy.join()); - } catch (Throwable fail) { threadUnexpectedException(fail); } + void checkCompletedWithWrappedCancellationException(CompletableFuture f) { + checkCompletedExceptionally(f, true, + (t) -> assertTrue(t instanceof CancellationException)); + } + + void checkCompletedWithTimeoutException(CompletableFuture f) { + checkCompletedExceptionally(f, false, + (t) -> assertTrue(t instanceof TimeoutException)); + } + + void checkCompletedWithWrappedException(CompletableFuture f, + Throwable ex) { + checkCompletedExceptionally(f, true, (t) -> assertSame(t, ex)); + } + + void checkCompletedExceptionally(CompletableFuture f, Throwable ex) { + checkCompletedExceptionally(f, false, (t) -> assertSame(t, ex)); } void checkCancelled(CompletableFuture f) { + long startTime = System.nanoTime(); try { f.get(LONG_DELAY_MS, MILLISECONDS); shouldThrow(); } catch (CancellationException success) { } catch (Throwable fail) { threadUnexpectedException(fail); } + assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS / 2); + try { f.join(); shouldThrow(); @@ -176,40 +191,12 @@ public class CompletableFutureTest exten shouldThrow(); } catch (CancellationException success) { } catch (Throwable fail) { threadUnexpectedException(fail); } - assertTrue(f.isDone()); - assertTrue(f.isCompletedExceptionally()); - assertTrue(f.isCancelled()); - assertTrue(f.toString().contains("[Completed exceptionally]")); - } - void checkCompletedWithWrappedCancellationException(CompletableFuture f) { - try { - f.get(LONG_DELAY_MS, MILLISECONDS); - shouldThrow(); - } catch (ExecutionException success) { - assertTrue(success.getCause() instanceof CancellationException); - } catch (Throwable fail) { threadUnexpectedException(fail); } - try { - f.join(); - shouldThrow(); - } catch (CompletionException success) { - assertTrue(success.getCause() instanceof CancellationException); - } - try { - f.getNow(null); - shouldThrow(); - } catch (CompletionException success) { - assertTrue(success.getCause() instanceof CancellationException); - } - try { - f.get(); - shouldThrow(); - } catch (ExecutionException success) { - assertTrue(success.getCause() instanceof CancellationException); - } catch (Throwable fail) { threadUnexpectedException(fail); } + assertTrue(exceptionalCompletion(f) instanceof CancellationException); + assertTrue(f.isDone()); - assertFalse(f.isCancelled()); assertTrue(f.isCompletedExceptionally()); + assertTrue(f.isCancelled()); assertTrue(f.toString().contains("[Completed exceptionally]")); } @@ -257,8 +244,9 @@ public class CompletableFutureTest exten { CompletableFuture f = new CompletableFuture<>(); checkIncomplete(f); - assertTrue(f.cancel(true)); - assertTrue(f.cancel(true)); + assertTrue(f.cancel(mayInterruptIfRunning)); + assertTrue(f.cancel(mayInterruptIfRunning)); + assertTrue(f.cancel(!mayInterruptIfRunning)); checkCancelled(f); }} @@ -530,7 +518,6 @@ public class CompletableFutureTest exten } } - class CompletableFutureInc extends CheckedIntegerAction implements Function> { @@ -569,12 +556,15 @@ public class CompletableFutureTest exten } } + static final boolean defaultExecutorIsCommonPool + = ForkJoinPool.getCommonPoolParallelism() > 1; + /** * Permits the testing of parallel code for the 3 different * execution modes without copy/pasting all the test methods. */ enum ExecutionMode { - DEFAULT { + SYNC { public void checkExecutionMode() { assertFalse(ThreadExecutor.startedCurrentThread()); assertNull(ForkJoinTask.getPool()); @@ -650,8 +640,8 @@ public class CompletableFutureTest exten ASYNC { public void checkExecutionMode() { - assertSame(ForkJoinPool.commonPool(), - ForkJoinTask.getPool()); + assertEquals(defaultExecutorIsCommonPool, + (ForkJoinPool.commonPool() == ForkJoinTask.getPool())); } public CompletableFuture runAsync(Runnable a) { return CompletableFuture.runAsync(a); @@ -850,9 +840,9 @@ public class CompletableFutureTest exten if (!createIncomplete) assertTrue(f.complete(v1)); final CompletableFuture g = f.exceptionally ((Throwable t) -> { - // Should not be called a.getAndIncrement(); - throw new AssertionError(); + threadFail("should not be called"); + return null; // unreached }); if (createIncomplete) assertTrue(f.complete(v1)); @@ -875,7 +865,7 @@ public class CompletableFutureTest exten if (!createIncomplete) f.completeExceptionally(ex); final CompletableFuture g = f.exceptionally ((Throwable t) -> { - ExecutionMode.DEFAULT.checkExecutionMode(); + ExecutionMode.SYNC.checkExecutionMode(); threadAssertSame(t, ex); a.getAndIncrement(); return v1; @@ -886,9 +876,12 @@ public class CompletableFutureTest exten assertEquals(1, a.get()); }} + /** + * If an "exceptionally action" throws an exception, it completes + * exceptionally with that exception + */ public void testExceptionally_exceptionalCompletionActionFailed() { for (boolean createIncomplete : new boolean[] { true, false }) - for (Integer v1 : new Integer[] { 1, null }) { final AtomicInteger a = new AtomicInteger(0); final CFException ex1 = new CFException(); @@ -897,7 +890,7 @@ public class CompletableFutureTest exten if (!createIncomplete) f.completeExceptionally(ex1); final CompletableFuture g = f.exceptionally ((Throwable t) -> { - ExecutionMode.DEFAULT.checkExecutionMode(); + ExecutionMode.SYNC.checkExecutionMode(); threadAssertSame(t, ex1); a.getAndIncrement(); throw ex2; @@ -905,6 +898,7 @@ public class CompletableFutureTest exten if (createIncomplete) f.completeExceptionally(ex1); checkCompletedWithWrappedException(g, ex2); + checkCompletedExceptionally(f, ex1); assertEquals(1, a.get()); }} @@ -912,7 +906,7 @@ public class CompletableFutureTest exten * whenComplete action executes on normal completion, propagating * source result. */ - public void testWhenComplete_normalCompletion1() { + public void testWhenComplete_normalCompletion() { for (ExecutionMode m : ExecutionMode.values()) for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) @@ -922,9 +916,9 @@ public class CompletableFutureTest exten if (!createIncomplete) assertTrue(f.complete(v1)); final CompletableFuture g = m.whenComplete (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertSame(x, v1); + threadAssertSame(result, v1); threadAssertNull(t); a.getAndIncrement(); }); @@ -942,7 +936,6 @@ public class CompletableFutureTest exten public void testWhenComplete_exceptionalCompletion() { for (ExecutionMode m : ExecutionMode.values()) for (boolean createIncomplete : new boolean[] { true, false }) - for (Integer v1 : new Integer[] { 1, null }) { final AtomicInteger a = new AtomicInteger(0); final CFException ex = new CFException(); @@ -950,9 +943,9 @@ public class CompletableFutureTest exten if (!createIncomplete) f.completeExceptionally(ex); final CompletableFuture g = m.whenComplete (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertNull(x); + threadAssertNull(result); threadAssertSame(t, ex); a.getAndIncrement(); }); @@ -977,9 +970,9 @@ public class CompletableFutureTest exten if (!createIncomplete) assertTrue(f.cancel(mayInterruptIfRunning)); final CompletableFuture g = m.whenComplete (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertNull(x); + threadAssertNull(result); threadAssertTrue(t instanceof CancellationException); a.getAndIncrement(); }); @@ -994,7 +987,7 @@ public class CompletableFutureTest exten * If a whenComplete action throws an exception when triggered by * a normal completion, it completes exceptionally */ - public void testWhenComplete_actionFailed() { + public void testWhenComplete_sourceCompletedNormallyActionFailed() { for (boolean createIncomplete : new boolean[] { true, false }) for (ExecutionMode m : ExecutionMode.values()) for (Integer v1 : new Integer[] { 1, null }) @@ -1005,9 +998,9 @@ public class CompletableFutureTest exten if (!createIncomplete) assertTrue(f.complete(v1)); final CompletableFuture g = m.whenComplete (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertSame(x, v1); + threadAssertSame(result, v1); threadAssertNull(t); a.getAndIncrement(); throw ex; @@ -1022,12 +1015,11 @@ public class CompletableFutureTest exten /** * If a whenComplete action throws an exception when triggered by * a source completion that also throws an exception, the source - * exception takes precedence. + * exception takes precedence (unlike handle) */ - public void testWhenComplete_actionFailedSourceFailed() { + public void testWhenComplete_sourceFailedActionFailed() { for (boolean createIncomplete : new boolean[] { true, false }) for (ExecutionMode m : ExecutionMode.values()) - for (Integer v1 : new Integer[] { 1, null }) { final AtomicInteger a = new AtomicInteger(0); final CFException ex1 = new CFException(); @@ -1037,10 +1029,10 @@ public class CompletableFutureTest exten if (!createIncomplete) f.completeExceptionally(ex1); final CompletableFuture g = m.whenComplete (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); threadAssertSame(t, ex1); - threadAssertNull(x); + threadAssertNull(result); a.getAndIncrement(); throw ex2; }); @@ -1048,6 +1040,10 @@ public class CompletableFutureTest exten checkCompletedWithWrappedException(g, ex1); checkCompletedExceptionally(f, ex1); + if (testImplementationDetails) { + assertEquals(1, ex1.getSuppressed().length); + assertSame(ex2, ex1.getSuppressed()[0]); + } assertEquals(1, a.get()); }} @@ -1065,9 +1061,9 @@ public class CompletableFutureTest exten if (!createIncomplete) assertTrue(f.complete(v1)); final CompletableFuture g = m.handle (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertSame(x, v1); + threadAssertSame(result, v1); threadAssertNull(t); a.getAndIncrement(); return inc(v1); @@ -1094,9 +1090,9 @@ public class CompletableFutureTest exten if (!createIncomplete) f.completeExceptionally(ex); final CompletableFuture g = m.handle (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertNull(x); + threadAssertNull(result); threadAssertSame(t, ex); a.getAndIncrement(); return v1; @@ -1123,9 +1119,9 @@ public class CompletableFutureTest exten if (!createIncomplete) assertTrue(f.cancel(mayInterruptIfRunning)); final CompletableFuture g = m.handle (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertNull(x); + threadAssertNull(result); threadAssertTrue(t instanceof CancellationException); a.getAndIncrement(); return v1; @@ -1138,55 +1134,62 @@ public class CompletableFutureTest exten }} /** - * handle result completes exceptionally if action does + * If a "handle action" throws an exception when triggered by + * a normal completion, it completes exceptionally */ - public void testHandle_sourceFailedActionFailed() { + public void testHandle_sourceCompletedNormallyActionFailed() { for (ExecutionMode m : ExecutionMode.values()) for (boolean createIncomplete : new boolean[] { true, false }) + for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); final AtomicInteger a = new AtomicInteger(0); - final CFException ex1 = new CFException(); - final CFException ex2 = new CFException(); - if (!createIncomplete) f.completeExceptionally(ex1); + final CFException ex = new CFException(); + if (!createIncomplete) assertTrue(f.complete(v1)); final CompletableFuture g = m.handle (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertNull(x); - threadAssertSame(ex1, t); + threadAssertSame(result, v1); + threadAssertNull(t); a.getAndIncrement(); - throw ex2; + throw ex; }); - if (createIncomplete) f.completeExceptionally(ex1); + if (createIncomplete) assertTrue(f.complete(v1)); - checkCompletedWithWrappedException(g, ex2); - checkCompletedExceptionally(f, ex1); + checkCompletedWithWrappedException(g, ex); + checkCompletedNormally(f, v1); assertEquals(1, a.get()); }} - public void testHandle_sourceCompletedNormallyActionFailed() { - for (ExecutionMode m : ExecutionMode.values()) + /** + * If a "handle action" throws an exception when triggered by + * a source completion that also throws an exception, the action + * exception takes precedence (unlike whenComplete) + */ + public void testHandle_sourceFailedActionFailed() { for (boolean createIncomplete : new boolean[] { true, false }) - for (Integer v1 : new Integer[] { 1, null }) + for (ExecutionMode m : ExecutionMode.values()) { - final CompletableFuture f = new CompletableFuture<>(); final AtomicInteger a = new AtomicInteger(0); - final CFException ex = new CFException(); - if (!createIncomplete) assertTrue(f.complete(v1)); + final CFException ex1 = new CFException(); + final CFException ex2 = new CFException(); + final CompletableFuture f = new CompletableFuture<>(); + + if (!createIncomplete) f.completeExceptionally(ex1); final CompletableFuture g = m.handle (f, - (Integer x, Throwable t) -> { + (Integer result, Throwable t) -> { m.checkExecutionMode(); - threadAssertSame(x, v1); - threadAssertNull(t); + threadAssertNull(result); + threadAssertSame(ex1, t); a.getAndIncrement(); - throw ex; + throw ex2; }); - if (createIncomplete) assertTrue(f.complete(v1)); + if (createIncomplete) f.completeExceptionally(ex1); - checkCompletedWithWrappedException(g, ex); - checkCompletedNormally(f, v1); + checkCompletedWithWrappedException(g, ex2); + checkCompletedExceptionally(f, ex1); assertEquals(1, a.get()); }} @@ -1264,21 +1267,31 @@ public class CompletableFutureTest exten */ public void testThenRun_normalCompletion() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); - final Noop r = new Noop(m); - if (!createIncomplete) assertTrue(f.complete(v1)); - final CompletableFuture g = m.thenRun(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.complete(v1)); - } + final Noop[] rs = new Noop[6]; + for (int i = 0; i < rs.length; i++) rs[i] = new Noop(m); - checkCompletedNormally(g, null); + final CompletableFuture h0 = m.thenRun(f, rs[0]); + final CompletableFuture h1 = m.runAfterBoth(f, f, rs[1]); + final CompletableFuture h2 = m.runAfterEither(f, f, rs[2]); + checkIncomplete(h0); + checkIncomplete(h1); + checkIncomplete(h2); + assertTrue(f.complete(v1)); + final CompletableFuture h3 = m.thenRun(f, rs[3]); + final CompletableFuture h4 = m.runAfterBoth(f, f, rs[4]); + final CompletableFuture h5 = m.runAfterEither(f, f, rs[5]); + + checkCompletedNormally(h0, null); + checkCompletedNormally(h1, null); + checkCompletedNormally(h2, null); + checkCompletedNormally(h3, null); + checkCompletedNormally(h4, null); + checkCompletedNormally(h5, null); checkCompletedNormally(f, v1); - r.assertInvoked(); + for (Noop r : rs) r.assertInvoked(); }} /** @@ -1287,21 +1300,31 @@ public class CompletableFutureTest exten */ public void testThenRun_exceptionalCompletion() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) { final CFException ex = new CFException(); final CompletableFuture f = new CompletableFuture<>(); - final Noop r = new Noop(m); - if (!createIncomplete) f.completeExceptionally(ex); - final CompletableFuture g = m.thenRun(f, r); - if (createIncomplete) { - checkIncomplete(g); - f.completeExceptionally(ex); - } + final Noop[] rs = new Noop[6]; + for (int i = 0; i < rs.length; i++) rs[i] = new Noop(m); - checkCompletedWithWrappedException(g, ex); + final CompletableFuture h0 = m.thenRun(f, rs[0]); + final CompletableFuture h1 = m.runAfterBoth(f, f, rs[1]); + final CompletableFuture h2 = m.runAfterEither(f, f, rs[2]); + checkIncomplete(h0); + checkIncomplete(h1); + checkIncomplete(h2); + assertTrue(f.completeExceptionally(ex)); + final CompletableFuture h3 = m.thenRun(f, rs[3]); + final CompletableFuture h4 = m.runAfterBoth(f, f, rs[4]); + final CompletableFuture h5 = m.runAfterEither(f, f, rs[5]); + + checkCompletedWithWrappedException(h0, ex); + checkCompletedWithWrappedException(h1, ex); + checkCompletedWithWrappedException(h2, ex); + checkCompletedWithWrappedException(h3, ex); + checkCompletedWithWrappedException(h4, ex); + checkCompletedWithWrappedException(h5, ex); checkCompletedExceptionally(f, ex); - r.assertNotInvoked(); + for (Noop r : rs) r.assertNotInvoked(); }} /** @@ -1309,21 +1332,31 @@ public class CompletableFutureTest exten */ public void testThenRun_sourceCancelled() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (boolean mayInterruptIfRunning : new boolean[] { true, false }) { final CompletableFuture f = new CompletableFuture<>(); - final Noop r = new Noop(m); - if (!createIncomplete) assertTrue(f.cancel(mayInterruptIfRunning)); - final CompletableFuture g = m.thenRun(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.cancel(mayInterruptIfRunning)); - } + final Noop[] rs = new Noop[6]; + for (int i = 0; i < rs.length; i++) rs[i] = new Noop(m); - checkCompletedWithWrappedCancellationException(g); + final CompletableFuture h0 = m.thenRun(f, rs[0]); + final CompletableFuture h1 = m.runAfterBoth(f, f, rs[1]); + final CompletableFuture h2 = m.runAfterEither(f, f, rs[2]); + checkIncomplete(h0); + checkIncomplete(h1); + checkIncomplete(h2); + assertTrue(f.cancel(mayInterruptIfRunning)); + final CompletableFuture h3 = m.thenRun(f, rs[3]); + final CompletableFuture h4 = m.runAfterBoth(f, f, rs[4]); + final CompletableFuture h5 = m.runAfterEither(f, f, rs[5]); + + checkCompletedWithWrappedCancellationException(h0); + checkCompletedWithWrappedCancellationException(h1); + checkCompletedWithWrappedCancellationException(h2); + checkCompletedWithWrappedCancellationException(h3); + checkCompletedWithWrappedCancellationException(h4); + checkCompletedWithWrappedCancellationException(h5); checkCancelled(f); - r.assertNotInvoked(); + for (Noop r : rs) r.assertNotInvoked(); }} /** @@ -1331,19 +1364,26 @@ public class CompletableFutureTest exten */ public void testThenRun_actionFailed() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); - final FailingRunnable r = new FailingRunnable(m); - if (!createIncomplete) assertTrue(f.complete(v1)); - final CompletableFuture g = m.thenRun(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.complete(v1)); - } + final FailingRunnable[] rs = new FailingRunnable[6]; + for (int i = 0; i < rs.length; i++) rs[i] = new FailingRunnable(m); - checkCompletedWithWrappedCFException(g); + final CompletableFuture h0 = m.thenRun(f, rs[0]); + final CompletableFuture h1 = m.runAfterBoth(f, f, rs[1]); + final CompletableFuture h2 = m.runAfterEither(f, f, rs[2]); + assertTrue(f.complete(v1)); + final CompletableFuture h3 = m.thenRun(f, rs[3]); + final CompletableFuture h4 = m.runAfterBoth(f, f, rs[4]); + final CompletableFuture h5 = m.runAfterEither(f, f, rs[5]); + + checkCompletedWithWrappedCFException(h0); + checkCompletedWithWrappedCFException(h1); + checkCompletedWithWrappedCFException(h2); + checkCompletedWithWrappedCFException(h3); + checkCompletedWithWrappedCFException(h4); + checkCompletedWithWrappedCFException(h5); checkCompletedNormally(f, v1); }} @@ -1352,21 +1392,26 @@ public class CompletableFutureTest exten */ public void testThenApply_normalCompletion() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); - final IncFunction r = new IncFunction(m); - if (!createIncomplete) assertTrue(f.complete(v1)); - final CompletableFuture g = m.thenApply(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.complete(v1)); - } + final IncFunction[] rs = new IncFunction[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new IncFunction(m); - checkCompletedNormally(g, inc(v1)); + final CompletableFuture h0 = m.thenApply(f, rs[0]); + final CompletableFuture h1 = m.applyToEither(f, f, rs[1]); + checkIncomplete(h0); + checkIncomplete(h1); + assertTrue(f.complete(v1)); + final CompletableFuture h2 = m.thenApply(f, rs[2]); + final CompletableFuture h3 = m.applyToEither(f, f, rs[3]); + + checkCompletedNormally(h0, inc(v1)); + checkCompletedNormally(h1, inc(v1)); + checkCompletedNormally(h2, inc(v1)); + checkCompletedNormally(h3, inc(v1)); checkCompletedNormally(f, v1); - r.assertValue(inc(v1)); + for (IncFunction r : rs) r.assertValue(inc(v1)); }} /** @@ -1375,21 +1420,24 @@ public class CompletableFutureTest exten */ public void testThenApply_exceptionalCompletion() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) { final CFException ex = new CFException(); final CompletableFuture f = new CompletableFuture<>(); - final IncFunction r = new IncFunction(m); - if (!createIncomplete) f.completeExceptionally(ex); - final CompletableFuture g = m.thenApply(f, r); - if (createIncomplete) { - checkIncomplete(g); - f.completeExceptionally(ex); - } + final IncFunction[] rs = new IncFunction[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new IncFunction(m); - checkCompletedWithWrappedException(g, ex); + final CompletableFuture h0 = m.thenApply(f, rs[0]); + final CompletableFuture h1 = m.applyToEither(f, f, rs[1]); + assertTrue(f.completeExceptionally(ex)); + final CompletableFuture h2 = m.thenApply(f, rs[2]); + final CompletableFuture h3 = m.applyToEither(f, f, rs[3]); + + checkCompletedWithWrappedException(h0, ex); + checkCompletedWithWrappedException(h1, ex); + checkCompletedWithWrappedException(h2, ex); + checkCompletedWithWrappedException(h3, ex); checkCompletedExceptionally(f, ex); - r.assertNotInvoked(); + for (IncFunction r : rs) r.assertNotInvoked(); }} /** @@ -1397,21 +1445,24 @@ public class CompletableFutureTest exten */ public void testThenApply_sourceCancelled() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (boolean mayInterruptIfRunning : new boolean[] { true, false }) { final CompletableFuture f = new CompletableFuture<>(); - final IncFunction r = new IncFunction(m); - if (!createIncomplete) assertTrue(f.cancel(mayInterruptIfRunning)); - final CompletableFuture g = m.thenApply(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.cancel(mayInterruptIfRunning)); - } + final IncFunction[] rs = new IncFunction[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new IncFunction(m); - checkCompletedWithWrappedCancellationException(g); + final CompletableFuture h0 = m.thenApply(f, rs[0]); + final CompletableFuture h1 = m.applyToEither(f, f, rs[1]); + assertTrue(f.cancel(mayInterruptIfRunning)); + final CompletableFuture h2 = m.thenApply(f, rs[2]); + final CompletableFuture h3 = m.applyToEither(f, f, rs[3]); + + checkCompletedWithWrappedCancellationException(h0); + checkCompletedWithWrappedCancellationException(h1); + checkCompletedWithWrappedCancellationException(h2); + checkCompletedWithWrappedCancellationException(h3); checkCancelled(f); - r.assertNotInvoked(); + for (IncFunction r : rs) r.assertNotInvoked(); }} /** @@ -1419,19 +1470,22 @@ public class CompletableFutureTest exten */ public void testThenApply_actionFailed() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); - final FailingFunction r = new FailingFunction(m); - if (!createIncomplete) assertTrue(f.complete(v1)); - final CompletableFuture g = m.thenApply(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.complete(v1)); - } + final FailingFunction[] rs = new FailingFunction[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new FailingFunction(m); - checkCompletedWithWrappedCFException(g); + final CompletableFuture h0 = m.thenApply(f, rs[0]); + final CompletableFuture h1 = m.applyToEither(f, f, rs[1]); + assertTrue(f.complete(v1)); + final CompletableFuture h2 = m.thenApply(f, rs[2]); + final CompletableFuture h3 = m.applyToEither(f, f, rs[3]); + + checkCompletedWithWrappedCFException(h0); + checkCompletedWithWrappedCFException(h1); + checkCompletedWithWrappedCFException(h2); + checkCompletedWithWrappedCFException(h3); checkCompletedNormally(f, v1); }} @@ -1440,21 +1494,26 @@ public class CompletableFutureTest exten */ public void testThenAccept_normalCompletion() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); - final NoopConsumer r = new NoopConsumer(m); - if (!createIncomplete) assertTrue(f.complete(v1)); - final CompletableFuture g = m.thenAccept(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.complete(v1)); - } + final NoopConsumer[] rs = new NoopConsumer[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new NoopConsumer(m); - checkCompletedNormally(g, null); - r.assertValue(v1); + final CompletableFuture h0 = m.thenAccept(f, rs[0]); + final CompletableFuture h1 = m.acceptEither(f, f, rs[1]); + checkIncomplete(h0); + checkIncomplete(h1); + assertTrue(f.complete(v1)); + final CompletableFuture h2 = m.thenAccept(f, rs[2]); + final CompletableFuture h3 = m.acceptEither(f, f, rs[3]); + + checkCompletedNormally(h0, null); + checkCompletedNormally(h1, null); + checkCompletedNormally(h2, null); + checkCompletedNormally(h3, null); checkCompletedNormally(f, v1); + for (NoopConsumer r : rs) r.assertValue(v1); }} /** @@ -1463,21 +1522,24 @@ public class CompletableFutureTest exten */ public void testThenAccept_exceptionalCompletion() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) { final CFException ex = new CFException(); final CompletableFuture f = new CompletableFuture<>(); - final NoopConsumer r = new NoopConsumer(m); - if (!createIncomplete) f.completeExceptionally(ex); - final CompletableFuture g = m.thenAccept(f, r); - if (createIncomplete) { - checkIncomplete(g); - f.completeExceptionally(ex); - } + final NoopConsumer[] rs = new NoopConsumer[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new NoopConsumer(m); - checkCompletedWithWrappedException(g, ex); + final CompletableFuture h0 = m.thenAccept(f, rs[0]); + final CompletableFuture h1 = m.acceptEither(f, f, rs[1]); + assertTrue(f.completeExceptionally(ex)); + final CompletableFuture h2 = m.thenAccept(f, rs[2]); + final CompletableFuture h3 = m.acceptEither(f, f, rs[3]); + + checkCompletedWithWrappedException(h0, ex); + checkCompletedWithWrappedException(h1, ex); + checkCompletedWithWrappedException(h2, ex); + checkCompletedWithWrappedException(h3, ex); checkCompletedExceptionally(f, ex); - r.assertNotInvoked(); + for (NoopConsumer r : rs) r.assertNotInvoked(); }} /** @@ -1485,21 +1547,24 @@ public class CompletableFutureTest exten */ public void testThenAccept_sourceCancelled() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (boolean mayInterruptIfRunning : new boolean[] { true, false }) { final CompletableFuture f = new CompletableFuture<>(); - final NoopConsumer r = new NoopConsumer(m); - if (!createIncomplete) assertTrue(f.cancel(mayInterruptIfRunning)); - final CompletableFuture g = m.thenAccept(f, r); - if (createIncomplete) { - checkIncomplete(g); - assertTrue(f.cancel(mayInterruptIfRunning)); - } + final NoopConsumer[] rs = new NoopConsumer[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new NoopConsumer(m); - checkCompletedWithWrappedCancellationException(g); + final CompletableFuture h0 = m.thenAccept(f, rs[0]); + final CompletableFuture h1 = m.acceptEither(f, f, rs[1]); + assertTrue(f.cancel(mayInterruptIfRunning)); + final CompletableFuture h2 = m.thenAccept(f, rs[2]); + final CompletableFuture h3 = m.acceptEither(f, f, rs[3]); + + checkCompletedWithWrappedCancellationException(h0); + checkCompletedWithWrappedCancellationException(h1); + checkCompletedWithWrappedCancellationException(h2); + checkCompletedWithWrappedCancellationException(h3); checkCancelled(f); - r.assertNotInvoked(); + for (NoopConsumer r : rs) r.assertNotInvoked(); }} /** @@ -1507,19 +1572,22 @@ public class CompletableFutureTest exten */ public void testThenAccept_actionFailed() { for (ExecutionMode m : ExecutionMode.values()) - for (boolean createIncomplete : new boolean[] { true, false }) for (Integer v1 : new Integer[] { 1, null }) { final CompletableFuture f = new CompletableFuture<>(); - final FailingConsumer r = new FailingConsumer(m); - if (!createIncomplete) f.complete(v1); - final CompletableFuture g = m.thenAccept(f, r); - if (createIncomplete) { - checkIncomplete(g); - f.complete(v1); - } + final FailingConsumer[] rs = new FailingConsumer[4]; + for (int i = 0; i < rs.length; i++) rs[i] = new FailingConsumer(m); - checkCompletedWithWrappedCFException(g); + final CompletableFuture h0 = m.thenAccept(f, rs[0]); + final CompletableFuture h1 = m.acceptEither(f, f, rs[1]); + assertTrue(f.complete(v1)); + final CompletableFuture h2 = m.thenAccept(f, rs[2]); + final CompletableFuture h3 = m.acceptEither(f, f, rs[3]); + + checkCompletedWithWrappedCFException(h0); + checkCompletedWithWrappedCFException(h1); + checkCompletedWithWrappedCFException(h2); + checkCompletedWithWrappedCFException(h3); checkCompletedNormally(f, v1); }} @@ -1535,31 +1603,35 @@ public class CompletableFutureTest exten { final CompletableFuture f = new CompletableFuture<>(); final CompletableFuture g = new CompletableFuture<>(); - final SubtractFunction r1 = new SubtractFunction(m); - final SubtractFunction r2 = new SubtractFunction(m); - final SubtractFunction r3 = new SubtractFunction(m); + final SubtractFunction[] rs = new SubtractFunction[6]; + for (int i = 0; i < rs.length; i++) rs[i] = new SubtractFunction(m); final CompletableFuture fst = fFirst ? f : g; final CompletableFuture snd = !fFirst ? f : g; final Integer w1 = fFirst ? v1 : v2; final Integer w2 = !fFirst ? v1 : v2; - final CompletableFuture h1 = m.thenCombine(f, g, r1); + final CompletableFuture h0 = m.thenCombine(f, g, rs[0]); + final CompletableFuture h1 = m.thenCombine(fst, fst, rs[1]); assertTrue(fst.complete(w1)); - final CompletableFuture h2 = m.thenCombine(f, g, r2); - checkIncomplete(h1); - checkIncomplete(h2); - r1.assertNotInvoked(); - r2.assertNotInvoked(); + final CompletableFuture h2 = m.thenCombine(f, g, rs[2]); + final CompletableFuture h3 = m.thenCombine(fst, fst, rs[3]); + checkIncomplete(h0); rs[0].assertNotInvoked(); + checkIncomplete(h2); rs[2].assertNotInvoked(); + checkCompletedNormally(h1, subtract(w1, w1)); + checkCompletedNormally(h3, subtract(w1, w1)); + rs[1].assertValue(subtract(w1, w1)); + rs[3].assertValue(subtract(w1, w1)); assertTrue(snd.complete(w2)); - final CompletableFuture h3 = m.thenCombine(f, g, r3); + final CompletableFuture h4 = m.thenCombine(f, g, rs[4]); - checkCompletedNormally(h1, subtract(v1, v2)); + checkCompletedNormally(h0, subtract(v1, v2)); checkCompletedNormally(h2, subtract(v1, v2)); - checkCompletedNormally(h3, subtract(v1, v2)); - r1.assertValue(subtract(v1, v2)); - r2.assertValue(subtract(v1, v2)); - r3.assertValue(subtract(v1, v2)); + checkCompletedNormally(h4, subtract(v1, v2)); + rs[0].assertValue(subtract(v1, v2)); + rs[2].assertValue(subtract(v1, v2)); + rs[4].assertValue(subtract(v1, v2)); + checkCompletedNormally(f, v1); checkCompletedNormally(g, v2); }} @@ -2906,6 +2978,58 @@ public class CompletableFutureTest exten checkCancelled(f); }} + /** + * thenCompose result completes exceptionally if the result of the action does + */ + public void testThenCompose_actionReturnsFailingFuture() { + for (ExecutionMode m : ExecutionMode.values()) + for (int order = 0; order < 6; order++) + for (Integer v1 : new Integer[] { 1, null }) + { + final CFException ex = new CFException(); + final CompletableFuture f = new CompletableFuture<>(); + final CompletableFuture g = new CompletableFuture<>(); + final CompletableFuture h; + // Test all permutations of orders + switch (order) { + case 0: + assertTrue(f.complete(v1)); + assertTrue(g.completeExceptionally(ex)); + h = m.thenCompose(f, (x -> g)); + break; + case 1: + assertTrue(f.complete(v1)); + h = m.thenCompose(f, (x -> g)); + assertTrue(g.completeExceptionally(ex)); + break; + case 2: + assertTrue(g.completeExceptionally(ex)); + assertTrue(f.complete(v1)); + h = m.thenCompose(f, (x -> g)); + break; + case 3: + assertTrue(g.completeExceptionally(ex)); + h = m.thenCompose(f, (x -> g)); + assertTrue(f.complete(v1)); + break; + case 4: + h = m.thenCompose(f, (x -> g)); + assertTrue(f.complete(v1)); + assertTrue(g.completeExceptionally(ex)); + break; + case 5: + h = m.thenCompose(f, (x -> g)); + assertTrue(f.complete(v1)); + assertTrue(g.completeExceptionally(ex)); + break; + default: throw new AssertionError(); + } + + checkCompletedExceptionally(g, ex); + checkCompletedWithWrappedException(h, ex); + checkCompletedNormally(f, v1); + }} + // other static methods /** @@ -2922,13 +3046,13 @@ public class CompletableFutureTest exten * when all components complete normally */ public void testAllOf_normal() throws Exception { - for (int k = 1; k < 20; ++k) { + for (int k = 1; k < 10; k++) { CompletableFuture[] fs = (CompletableFuture[]) new CompletableFuture[k]; - for (int i = 0; i < k; ++i) + for (int i = 0; i < k; i++) fs[i] = new CompletableFuture<>(); CompletableFuture f = CompletableFuture.allOf(fs); - for (int i = 0; i < k; ++i) { + for (int i = 0; i < k; i++) { checkIncomplete(f); checkIncomplete(CompletableFuture.allOf(fs)); fs[i].complete(one); @@ -2939,10 +3063,10 @@ public class CompletableFutureTest exten } public void testAllOf_backwards() throws Exception { - for (int k = 1; k < 20; ++k) { + for (int k = 1; k < 10; k++) { CompletableFuture[] fs = (CompletableFuture[]) new CompletableFuture[k]; - for (int i = 0; i < k; ++i) + for (int i = 0; i < k; i++) fs[i] = new CompletableFuture<>(); CompletableFuture f = CompletableFuture.allOf(fs); for (int i = k - 1; i >= 0; i--) { @@ -2955,29 +3079,74 @@ public class CompletableFutureTest exten } } + public void testAllOf_exceptional() throws Exception { + for (int k = 1; k < 10; k++) { + CompletableFuture[] fs + = (CompletableFuture[]) new CompletableFuture[k]; + CFException ex = new CFException(); + for (int i = 0; i < k; i++) + fs[i] = new CompletableFuture<>(); + CompletableFuture f = CompletableFuture.allOf(fs); + for (int i = 0; i < k; i++) { + checkIncomplete(f); + checkIncomplete(CompletableFuture.allOf(fs)); + if (i != k / 2) { + fs[i].complete(i); + checkCompletedNormally(fs[i], i); + } else { + fs[i].completeExceptionally(ex); + checkCompletedExceptionally(fs[i], ex); + } + } + checkCompletedWithWrappedException(f, ex); + checkCompletedWithWrappedException(CompletableFuture.allOf(fs), ex); + } + } + /** * anyOf(no component futures) returns an incomplete future */ public void testAnyOf_empty() throws Exception { + for (Integer v1 : new Integer[] { 1, null }) + { CompletableFuture f = CompletableFuture.anyOf(); checkIncomplete(f); - } + + f.complete(v1); + checkCompletedNormally(f, v1); + }} /** * anyOf returns a future completed normally with a value when * a component future does */ public void testAnyOf_normal() throws Exception { - for (int k = 0; k < 10; ++k) { + for (int k = 0; k < 10; k++) { CompletableFuture[] fs = new CompletableFuture[k]; - for (int i = 0; i < k; ++i) + for (int i = 0; i < k; i++) fs[i] = new CompletableFuture<>(); CompletableFuture f = CompletableFuture.anyOf(fs); checkIncomplete(f); - for (int i = 0; i < k; ++i) { - fs[i].complete(one); - checkCompletedNormally(f, one); - checkCompletedNormally(CompletableFuture.anyOf(fs), one); + for (int i = 0; i < k; i++) { + fs[i].complete(i); + checkCompletedNormally(f, 0); + int x = (int) CompletableFuture.anyOf(fs).join(); + assertTrue(0 <= x && x <= i); + } + } + } + public void testAnyOf_normal_backwards() throws Exception { + for (int k = 0; k < 10; k++) { + CompletableFuture[] fs = new CompletableFuture[k]; + for (int i = 0; i < k; i++) + fs[i] = new CompletableFuture<>(); + CompletableFuture f = CompletableFuture.anyOf(fs); + checkIncomplete(f); + for (int i = k - 1; i >= 0; i--) { + fs[i].complete(i); + checkCompletedNormally(f, k - 1); + int x = (int) CompletableFuture.anyOf(fs).join(); + assertTrue(i <= x && x <= k - 1); } } } @@ -2986,15 +3155,36 @@ public class CompletableFutureTest exten * anyOf result completes exceptionally when any component does. */ public void testAnyOf_exceptional() throws Exception { - for (int k = 0; k < 10; ++k) { + for (int k = 0; k < 10; k++) { CompletableFuture[] fs = new CompletableFuture[k]; - for (int i = 0; i < k; ++i) + CFException[] exs = new CFException[k]; + for (int i = 0; i < k; i++) { fs[i] = new CompletableFuture<>(); + exs[i] = new CFException(); + } CompletableFuture f = CompletableFuture.anyOf(fs); checkIncomplete(f); - for (int i = 0; i < k; ++i) { - fs[i].completeExceptionally(new CFException()); - checkCompletedWithWrappedCFException(f); + for (int i = 0; i < k; i++) { + fs[i].completeExceptionally(exs[i]); + checkCompletedWithWrappedException(f, exs[0]); + checkCompletedWithWrappedCFException(CompletableFuture.anyOf(fs)); + } + } + } + + public void testAnyOf_exceptional_backwards() throws Exception { + for (int k = 0; k < 10; k++) { + CompletableFuture[] fs = new CompletableFuture[k]; + CFException[] exs = new CFException[k]; + for (int i = 0; i < k; i++) { + fs[i] = new CompletableFuture<>(); + exs[i] = new CFException(); + } + CompletableFuture f = CompletableFuture.anyOf(fs); + checkIncomplete(f); + for (int i = k - 1; i >= 0; i--) { + fs[i].completeExceptionally(exs[i]); + checkCompletedWithWrappedException(f, exs[k - 1]); checkCompletedWithWrappedCFException(CompletableFuture.anyOf(fs)); } } @@ -3007,13 +3197,12 @@ public class CompletableFutureTest exten CompletableFuture f = new CompletableFuture<>(); CompletableFuture g = new CompletableFuture<>(); CompletableFuture nullFuture = (CompletableFuture)null; - CompletableFuture h; ThreadExecutor exec = new ThreadExecutor(); Runnable[] throwingActions = { () -> CompletableFuture.supplyAsync(null), () -> CompletableFuture.supplyAsync(null, exec), - () -> CompletableFuture.supplyAsync(new IntegerSupplier(ExecutionMode.DEFAULT, 42), null), + () -> CompletableFuture.supplyAsync(new IntegerSupplier(ExecutionMode.SYNC, 42), null), () -> CompletableFuture.runAsync(null), () -> CompletableFuture.runAsync(null, exec), @@ -3104,6 +3293,16 @@ public class CompletableFutureTest exten () -> CompletableFuture.anyOf(null, f), () -> f.obtrudeException(null), + + () -> CompletableFuture.delayedExecutor(1L, SECONDS, null), + () -> CompletableFuture.delayedExecutor(1L, null, exec), + () -> CompletableFuture.delayedExecutor(1L, null), + + () -> f.orTimeout(1L, null), + () -> f.completeOnTimeout(42, 1L, null), + + () -> CompletableFuture.failedFuture(null), + () -> CompletableFuture.failedStage(null), }; assertThrows(NullPointerException.class, throwingActions); @@ -3118,15 +3317,340 @@ public class CompletableFutureTest exten assertSame(f, f.toCompletableFuture()); } + // jdk9 + + /** + * newIncompleteFuture returns an incomplete CompletableFuture + */ + public void testNewIncompleteFuture() { + for (Integer v1 : new Integer[] { 1, null }) + { + CompletableFuture f = new CompletableFuture<>(); + CompletableFuture g = f.newIncompleteFuture(); + checkIncomplete(f); + checkIncomplete(g); + f.complete(v1); + checkCompletedNormally(f, v1); + checkIncomplete(g); + g.complete(v1); + checkCompletedNormally(g, v1); + assertSame(g.getClass(), CompletableFuture.class); + }} + + /** + * completedStage returns a completed CompletionStage + */ + public void testCompletedStage() { + AtomicInteger x = new AtomicInteger(0); + AtomicReference r = new AtomicReference(); + CompletionStage f = CompletableFuture.completedStage(1); + f.whenComplete((v, e) -> {if (e != null) r.set(e); else x.set(v);}); + assertEquals(x.get(), 1); + assertNull(r.get()); + } + + /** + * defaultExecutor by default returns the commonPool if + * it supports more than one thread. + */ + public void testDefaultExecutor() { + CompletableFuture f = new CompletableFuture<>(); + Executor e = f.defaultExecutor(); + Executor c = ForkJoinPool.commonPool(); + if (ForkJoinPool.getCommonPoolParallelism() > 1) + assertSame(e, c); + else + assertNotSame(e, c); + } + + /** + * failedFuture returns a CompletableFuture completed + * exceptionally with the given Exception + */ + public void testFailedFuture() { + CFException ex = new CFException(); + CompletableFuture f = CompletableFuture.failedFuture(ex); + checkCompletedExceptionally(f, ex); + } + + /** + * failedFuture(null) throws NPE + */ + public void testFailedFuture_null() { + try { + CompletableFuture f = CompletableFuture.failedFuture(null); + shouldThrow(); + } catch (NullPointerException success) {} + } + + /** + * copy returns a CompletableFuture that is completed normally, + * with the same value, when source is. + */ + public void testCopy() { + CompletableFuture f = new CompletableFuture<>(); + CompletableFuture g = f.copy(); + checkIncomplete(f); + checkIncomplete(g); + f.complete(1); + checkCompletedNormally(f, 1); + checkCompletedNormally(g, 1); + } + + /** + * copy returns a CompletableFuture that is completed exceptionally + * when source is. + */ + public void testCopy2() { + CompletableFuture f = new CompletableFuture<>(); + CompletableFuture g = f.copy(); + checkIncomplete(f); + checkIncomplete(g); + CFException ex = new CFException(); + f.completeExceptionally(ex); + checkCompletedExceptionally(f, ex); + checkCompletedWithWrappedException(g, ex); + } + + /** + * minimalCompletionStage returns a CompletableFuture that is + * completed normally, with the same value, when source is. + */ + public void testMinimalCompletionStage() { + CompletableFuture f = new CompletableFuture<>(); + CompletionStage g = f.minimalCompletionStage(); + AtomicInteger x = new AtomicInteger(0); + AtomicReference r = new AtomicReference(); + checkIncomplete(f); + g.whenComplete((v, e) -> {if (e != null) r.set(e); else x.set(v);}); + f.complete(1); + checkCompletedNormally(f, 1); + assertEquals(x.get(), 1); + assertNull(r.get()); + } + + /** + * minimalCompletionStage returns a CompletableFuture that is + * completed exceptionally when source is. + */ + public void testMinimalCompletionStage2() { + CompletableFuture f = new CompletableFuture<>(); + CompletionStage g = f.minimalCompletionStage(); + AtomicInteger x = new AtomicInteger(0); + AtomicReference r = new AtomicReference(); + g.whenComplete((v, e) -> {if (e != null) r.set(e); else x.set(v);}); + checkIncomplete(f); + CFException ex = new CFException(); + f.completeExceptionally(ex); + checkCompletedExceptionally(f, ex); + assertEquals(x.get(), 0); + assertEquals(r.get().getCause(), ex); + } + + /** + * failedStage returns a CompletionStage completed + * exceptionally with the given Exception + */ + public void testFailedStage() { + CFException ex = new CFException(); + CompletionStage f = CompletableFuture.failedStage(ex); + AtomicInteger x = new AtomicInteger(0); + AtomicReference r = new AtomicReference(); + f.whenComplete((v, e) -> {if (e != null) r.set(e); else x.set(v);}); + assertEquals(x.get(), 0); + assertEquals(r.get(), ex); + } + + /** + * completeAsync completes with value of given supplier + */ + public void testCompleteAsync() { + for (Integer v1 : new Integer[] { 1, null }) + { + CompletableFuture f = new CompletableFuture<>(); + f.completeAsync(() -> v1); + f.join(); + checkCompletedNormally(f, v1); + }} + + /** + * completeAsync completes exceptionally if given supplier throws + */ + public void testCompleteAsync2() { + CompletableFuture f = new CompletableFuture<>(); + CFException ex = new CFException(); + f.completeAsync(() -> {if (true) throw ex; return 1;}); + try { + f.join(); + shouldThrow(); + } catch (CompletionException success) {} + checkCompletedWithWrappedException(f, ex); + } + + /** + * completeAsync with given executor completes with value of given supplier + */ + public void testCompleteAsync3() { + for (Integer v1 : new Integer[] { 1, null }) + { + CompletableFuture f = new CompletableFuture<>(); + ThreadExecutor executor = new ThreadExecutor(); + f.completeAsync(() -> v1, executor); + assertSame(v1, f.join()); + checkCompletedNormally(f, v1); + assertEquals(1, executor.count.get()); + }} + + /** + * completeAsync with given executor completes exceptionally if + * given supplier throws + */ + public void testCompleteAsync4() { + CompletableFuture f = new CompletableFuture<>(); + CFException ex = new CFException(); + ThreadExecutor executor = new ThreadExecutor(); + f.completeAsync(() -> {if (true) throw ex; return 1;}, executor); + try { + f.join(); + shouldThrow(); + } catch (CompletionException success) {} + checkCompletedWithWrappedException(f, ex); + assertEquals(1, executor.count.get()); + } + + /** + * orTimeout completes with TimeoutException if not complete + */ + public void testOrTimeout_timesOut() { + long timeoutMillis = timeoutMillis(); + CompletableFuture f = new CompletableFuture<>(); + long startTime = System.nanoTime(); + assertSame(f, f.orTimeout(timeoutMillis, MILLISECONDS)); + checkCompletedWithTimeoutException(f); + assertTrue(millisElapsedSince(startTime) >= timeoutMillis); + } + + /** + * orTimeout completes normally if completed before timeout + */ + public void testOrTimeout_completed() { + for (Integer v1 : new Integer[] { 1, null }) + { + CompletableFuture f = new CompletableFuture<>(); + CompletableFuture g = new CompletableFuture<>(); + long startTime = System.nanoTime(); + f.complete(v1); + assertSame(f, f.orTimeout(LONG_DELAY_MS, MILLISECONDS)); + assertSame(g, g.orTimeout(LONG_DELAY_MS, MILLISECONDS)); + g.complete(v1); + checkCompletedNormally(f, v1); + checkCompletedNormally(g, v1); + assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS / 2); + }} + + /** + * completeOnTimeout completes with given value if not complete + */ + public void testCompleteOnTimeout_timesOut() { + testInParallel(() -> testCompleteOnTimeout_timesOut(42), + () -> testCompleteOnTimeout_timesOut(null)); + } + + /** + * completeOnTimeout completes with given value if not complete + */ + public void testCompleteOnTimeout_timesOut(Integer v) { + long timeoutMillis = timeoutMillis(); + CompletableFuture f = new CompletableFuture<>(); + long startTime = System.nanoTime(); + assertSame(f, f.completeOnTimeout(v, timeoutMillis, MILLISECONDS)); + assertSame(v, f.join()); + assertTrue(millisElapsedSince(startTime) >= timeoutMillis); + f.complete(99); // should have no effect + checkCompletedNormally(f, v); + } + + /** + * completeOnTimeout has no effect if completed within timeout + */ + public void testCompleteOnTimeout_completed() { + for (Integer v1 : new Integer[] { 1, null }) + { + CompletableFuture f = new CompletableFuture<>(); + CompletableFuture g = new CompletableFuture<>(); + long startTime = System.nanoTime(); + f.complete(v1); + assertSame(f, f.completeOnTimeout(-1, LONG_DELAY_MS, MILLISECONDS)); + assertSame(g, g.completeOnTimeout(-1, LONG_DELAY_MS, MILLISECONDS)); + g.complete(v1); + checkCompletedNormally(f, v1); + checkCompletedNormally(g, v1); + assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS / 2); + }} + + /** + * delayedExecutor returns an executor that delays submission + */ + public void testDelayedExecutor() { + testInParallel(() -> testDelayedExecutor(null, null), + () -> testDelayedExecutor(null, 1), + () -> testDelayedExecutor(new ThreadExecutor(), 1), + () -> testDelayedExecutor(new ThreadExecutor(), 1)); + } + + public void testDelayedExecutor(Executor executor, Integer v) throws Exception { + long timeoutMillis = timeoutMillis(); + // Use an "unreasonably long" long timeout to catch lingering threads + long longTimeoutMillis = 1000 * 60 * 60 * 24; + final Executor delayer, longDelayer; + if (executor == null) { + delayer = CompletableFuture.delayedExecutor(timeoutMillis, MILLISECONDS); + longDelayer = CompletableFuture.delayedExecutor(longTimeoutMillis, MILLISECONDS); + } else { + delayer = CompletableFuture.delayedExecutor(timeoutMillis, MILLISECONDS, executor); + longDelayer = CompletableFuture.delayedExecutor(longTimeoutMillis, MILLISECONDS, executor); + } + long startTime = System.nanoTime(); + CompletableFuture f = + CompletableFuture.supplyAsync(() -> v, delayer); + CompletableFuture g = + CompletableFuture.supplyAsync(() -> v, longDelayer); + + assertNull(g.getNow(null)); + + assertSame(v, f.get(LONG_DELAY_MS, MILLISECONDS)); + long millisElapsed = millisElapsedSince(startTime); + assertTrue(millisElapsed >= timeoutMillis); + assertTrue(millisElapsed < LONG_DELAY_MS / 2); + + checkCompletedNormally(f, v); + + checkIncomplete(g); + assertTrue(g.cancel(true)); + } + //--- tests of implementation details; not part of official tck --- Object resultOf(CompletableFuture f) { + SecurityManager sm = System.getSecurityManager(); + if (sm != null) { + try { + System.setSecurityManager(null); + } catch (SecurityException giveUp) { + return "Reflection not available"; + } + } + try { java.lang.reflect.Field resultField = CompletableFuture.class.getDeclaredField("result"); resultField.setAccessible(true); return resultField.get(f); - } catch (Throwable t) { throw new AssertionError(t); } + } catch (Throwable t) { + throw new AssertionError(t); + } finally { + if (sm != null) System.setSecurityManager(sm); + } } public void testExceptionPropagationReusesResultObject() { @@ -3137,44 +3661,51 @@ public class CompletableFutureTest exten final CompletableFuture v42 = CompletableFuture.completedFuture(42); final CompletableFuture incomplete = new CompletableFuture<>(); - List, CompletableFuture>> dependentFactories + List, CompletableFuture>> funs = new ArrayList<>(); - dependentFactories.add((y) -> m.thenRun(y, new Noop(m))); - dependentFactories.add((y) -> m.thenAccept(y, new NoopConsumer(m))); - dependentFactories.add((y) -> m.thenApply(y, new IncFunction(m))); - - dependentFactories.add((y) -> m.runAfterEither(y, incomplete, new Noop(m))); - dependentFactories.add((y) -> m.acceptEither(y, incomplete, new NoopConsumer(m))); - dependentFactories.add((y) -> m.applyToEither(y, incomplete, new IncFunction(m))); - - dependentFactories.add((y) -> m.runAfterBoth(y, v42, new Noop(m))); - dependentFactories.add((y) -> m.thenAcceptBoth(y, v42, new SubtractAction(m))); - dependentFactories.add((y) -> m.thenCombine(y, v42, new SubtractFunction(m))); - - dependentFactories.add((y) -> m.whenComplete(y, (Integer x, Throwable t) -> {})); - - dependentFactories.add((y) -> m.thenCompose(y, new CompletableFutureInc(m))); - - dependentFactories.add((y) -> CompletableFuture.allOf(new CompletableFuture[] {y, v42})); - dependentFactories.add((y) -> CompletableFuture.anyOf(new CompletableFuture[] {y, incomplete})); + funs.add((y) -> m.thenRun(y, new Noop(m))); + funs.add((y) -> m.thenAccept(y, new NoopConsumer(m))); + funs.add((y) -> m.thenApply(y, new IncFunction(m))); + + funs.add((y) -> m.runAfterEither(y, incomplete, new Noop(m))); + funs.add((y) -> m.acceptEither(y, incomplete, new NoopConsumer(m))); + funs.add((y) -> m.applyToEither(y, incomplete, new IncFunction(m))); + + funs.add((y) -> m.runAfterBoth(y, v42, new Noop(m))); + funs.add((y) -> m.runAfterBoth(v42, y, new Noop(m))); + funs.add((y) -> m.thenAcceptBoth(y, v42, new SubtractAction(m))); + funs.add((y) -> m.thenAcceptBoth(v42, y, new SubtractAction(m))); + funs.add((y) -> m.thenCombine(y, v42, new SubtractFunction(m))); + funs.add((y) -> m.thenCombine(v42, y, new SubtractFunction(m))); + + funs.add((y) -> m.whenComplete(y, (Integer r, Throwable t) -> {})); + + funs.add((y) -> m.thenCompose(y, new CompletableFutureInc(m))); + + funs.add((y) -> CompletableFuture.allOf(new CompletableFuture[] {y})); + funs.add((y) -> CompletableFuture.allOf(new CompletableFuture[] {y, v42})); + funs.add((y) -> CompletableFuture.allOf(new CompletableFuture[] {v42, y})); + funs.add((y) -> CompletableFuture.anyOf(new CompletableFuture[] {y})); + funs.add((y) -> CompletableFuture.anyOf(new CompletableFuture[] {y, incomplete})); + funs.add((y) -> CompletableFuture.anyOf(new CompletableFuture[] {incomplete, y})); for (Function, CompletableFuture> - dependentFactory : dependentFactories) { + fun : funs) { CompletableFuture f = new CompletableFuture<>(); f.completeExceptionally(ex); CompletableFuture src = m.thenApply(f, new IncFunction(m)); checkCompletedWithWrappedException(src, ex); - CompletableFuture dep = dependentFactory.apply(src); + CompletableFuture dep = fun.apply(src); checkCompletedWithWrappedException(dep, ex); assertSame(resultOf(src), resultOf(dep)); } for (Function, CompletableFuture> - dependentFactory : dependentFactories) { + fun : funs) { CompletableFuture f = new CompletableFuture<>(); CompletableFuture src = m.thenApply(f, new IncFunction(m)); - CompletableFuture dep = dependentFactory.apply(src); + CompletableFuture dep = fun.apply(src); f.completeExceptionally(ex); checkCompletedWithWrappedException(src, ex); checkCompletedWithWrappedException(dep, ex); @@ -3183,23 +3714,23 @@ public class CompletableFutureTest exten for (boolean mayInterruptIfRunning : new boolean[] { true, false }) for (Function, CompletableFuture> - dependentFactory : dependentFactories) { + fun : funs) { CompletableFuture f = new CompletableFuture<>(); f.cancel(mayInterruptIfRunning); checkCancelled(f); CompletableFuture src = m.thenApply(f, new IncFunction(m)); checkCompletedWithWrappedCancellationException(src); - CompletableFuture dep = dependentFactory.apply(src); + CompletableFuture dep = fun.apply(src); checkCompletedWithWrappedCancellationException(dep); assertSame(resultOf(src), resultOf(dep)); } for (boolean mayInterruptIfRunning : new boolean[] { true, false }) for (Function, CompletableFuture> - dependentFactory : dependentFactories) { + fun : funs) { CompletableFuture f = new CompletableFuture<>(); CompletableFuture src = m.thenApply(f, new IncFunction(m)); - CompletableFuture dep = dependentFactory.apply(src); + CompletableFuture dep = fun.apply(src); f.cancel(mayInterruptIfRunning); checkCancelled(f); checkCompletedWithWrappedCancellationException(src); @@ -3208,4 +3739,269 @@ public class CompletableFutureTest exten } }} + /** + * Minimal completion stages throw UOE for all non-CompletionStage methods + */ + public void testMinimalCompletionStage_minimality() { + if (!testImplementationDetails) return; + Function toSignature = + (method) -> method.getName() + Arrays.toString(method.getParameterTypes()); + Predicate isNotStatic = + (method) -> (method.getModifiers() & Modifier.STATIC) == 0; + List minimalMethods = + Stream.of(Object.class, CompletionStage.class) + .flatMap((klazz) -> Stream.of(klazz.getMethods())) + .filter(isNotStatic) + .collect(Collectors.toList()); + // Methods from CompletableFuture permitted NOT to throw UOE + String[] signatureWhitelist = { + "newIncompleteFuture[]", + "defaultExecutor[]", + "minimalCompletionStage[]", + "copy[]", + }; + Set permittedMethodSignatures = + Stream.concat(minimalMethods.stream().map(toSignature), + Stream.of(signatureWhitelist)) + .collect(Collectors.toSet()); + List allMethods = Stream.of(CompletableFuture.class.getMethods()) + .filter(isNotStatic) + .filter((method) -> !permittedMethodSignatures.contains(toSignature.apply(method))) + .collect(Collectors.toList()); + + CompletionStage minimalStage = + new CompletableFuture().minimalCompletionStage(); + + List bugs = new ArrayList<>(); + for (Method method : allMethods) { + Class[] parameterTypes = method.getParameterTypes(); + Object[] args = new Object[parameterTypes.length]; + // Manufacture boxed primitives for primitive params + for (int i = 0; i < args.length; i++) { + Class type = parameterTypes[i]; + if (parameterTypes[i] == boolean.class) + args[i] = false; + else if (parameterTypes[i] == int.class) + args[i] = 0; + else if (parameterTypes[i] == long.class) + args[i] = 0L; + } + try { + method.invoke(minimalStage, args); + bugs.add(method); + } + catch (java.lang.reflect.InvocationTargetException expected) { + if (! (expected.getCause() instanceof UnsupportedOperationException)) { + bugs.add(method); + // expected.getCause().printStackTrace(); + } + } + catch (ReflectiveOperationException bad) { throw new Error(bad); } + } + if (!bugs.isEmpty()) + throw new Error("Methods did not throw UOE: " + bugs.toString()); + } + + static class Monad { + static class ZeroException extends RuntimeException { + public ZeroException() { super("monadic zero"); } + } + // "return", "unit" + static CompletableFuture unit(T value) { + return completedFuture(value); + } + // monadic zero ? + static CompletableFuture zero() { + return failedFuture(new ZeroException()); + } + // >=> + static Function> compose + (Function> f, + Function> g) { + return (x) -> f.apply(x).thenCompose(g); + } + + static void assertZero(CompletableFuture f) { + try { + f.getNow(null); + throw new AssertionFailedError("should throw"); + } catch (CompletionException success) { + assertTrue(success.getCause() instanceof ZeroException); + } + } + + static void assertFutureEquals(CompletableFuture f, + CompletableFuture g) { + T fval = null, gval = null; + Throwable fex = null, gex = null; + + try { fval = f.get(); } + catch (ExecutionException ex) { fex = ex.getCause(); } + catch (Throwable ex) { fex = ex; } + + try { gval = g.get(); } + catch (ExecutionException ex) { gex = ex.getCause(); } + catch (Throwable ex) { gex = ex; } + + if (fex != null || gex != null) + assertSame(fex.getClass(), gex.getClass()); + else + assertEquals(fval, gval); + } + + static class PlusFuture extends CompletableFuture { + AtomicReference firstFailure = new AtomicReference<>(null); + } + + /** Implements "monadic plus". */ + static CompletableFuture plus(CompletableFuture f, + CompletableFuture g) { + PlusFuture plus = new PlusFuture(); + BiConsumer action = (T result, Throwable ex) -> { + try { + if (ex == null) { + if (plus.complete(result)) + if (plus.firstFailure.get() != null) + plus.firstFailure.set(null); + } + else if (plus.firstFailure.compareAndSet(null, ex)) { + if (plus.isDone()) + plus.firstFailure.set(null); + } + else { + // first failure has precedence + Throwable first = plus.firstFailure.getAndSet(null); + + // may fail with "Self-suppression not permitted" + try { first.addSuppressed(ex); } + catch (Exception ignored) {} + + plus.completeExceptionally(first); + } + } catch (Throwable unexpected) { + plus.completeExceptionally(unexpected); + } + }; + f.whenComplete(action); + g.whenComplete(action); + return plus; + } + } + + /** + * CompletableFuture is an additive monad - sort of. + * https://en.wikipedia.org/wiki/Monad_(functional_programming)#Additive_monads + */ + public void testAdditiveMonad() throws Throwable { + Function> unit = Monad::unit; + CompletableFuture zero = Monad.zero(); + + // Some mutually non-commutative functions + Function> triple + = (x) -> Monad.unit(3 * x); + Function> inc + = (x) -> Monad.unit(x + 1); + + // unit is a right identity: m >>= unit === m + Monad.assertFutureEquals(inc.apply(5L).thenCompose(unit), + inc.apply(5L)); + // unit is a left identity: (unit x) >>= f === f x + Monad.assertFutureEquals(unit.apply(5L).thenCompose(inc), + inc.apply(5L)); + + // associativity: (m >>= f) >>= g === m >>= ( \x -> (f x >>= g) ) + Monad.assertFutureEquals( + unit.apply(5L).thenCompose(inc).thenCompose(triple), + unit.apply(5L).thenCompose((x) -> inc.apply(x).thenCompose(triple))); + + // The case for CompletableFuture as an additive monad is weaker... + + // zero is a monadic zero + Monad.assertZero(zero); + + // left zero: zero >>= f === zero + Monad.assertZero(zero.thenCompose(inc)); + // right zero: f >>= (\x -> zero) === zero + Monad.assertZero(inc.apply(5L).thenCompose((x) -> zero)); + + // f plus zero === f + Monad.assertFutureEquals(Monad.unit(5L), + Monad.plus(Monad.unit(5L), zero)); + // zero plus f === f + Monad.assertFutureEquals(Monad.unit(5L), + Monad.plus(zero, Monad.unit(5L))); + // zero plus zero === zero + Monad.assertZero(Monad.plus(zero, zero)); + { + CompletableFuture f = Monad.plus(Monad.unit(5L), + Monad.unit(8L)); + // non-determinism + assertTrue(f.get() == 5L || f.get() == 8L); + } + + CompletableFuture godot = new CompletableFuture<>(); + // f plus godot === f (doesn't wait for godot) + Monad.assertFutureEquals(Monad.unit(5L), + Monad.plus(Monad.unit(5L), godot)); + // godot plus f === f (doesn't wait for godot) + Monad.assertFutureEquals(Monad.unit(5L), + Monad.plus(godot, Monad.unit(5L))); + } + + /** + * A single CompletableFuture with many dependents. + * A demo of scalability - runtime is O(n). + */ + public void testManyDependents() throws Throwable { + final int n = 1_000; + final CompletableFuture head = new CompletableFuture<>(); + final CompletableFuture complete = CompletableFuture.completedFuture((Void)null); + final AtomicInteger count = new AtomicInteger(0); + for (int i = 0; i < n; i++) { + head.thenRun(() -> count.getAndIncrement()); + head.thenAccept((x) -> count.getAndIncrement()); + head.thenApply((x) -> count.getAndIncrement()); + + head.runAfterBoth(complete, () -> count.getAndIncrement()); + head.thenAcceptBoth(complete, (x, y) -> count.getAndIncrement()); + head.thenCombine(complete, (x, y) -> count.getAndIncrement()); + complete.runAfterBoth(head, () -> count.getAndIncrement()); + complete.thenAcceptBoth(head, (x, y) -> count.getAndIncrement()); + complete.thenCombine(head, (x, y) -> count.getAndIncrement()); + + head.runAfterEither(new CompletableFuture(), () -> count.getAndIncrement()); + head.acceptEither(new CompletableFuture(), (x) -> count.getAndIncrement()); + head.applyToEither(new CompletableFuture(), (x) -> count.getAndIncrement()); + new CompletableFuture().runAfterEither(head, () -> count.getAndIncrement()); + new CompletableFuture().acceptEither(head, (x) -> count.getAndIncrement()); + new CompletableFuture().applyToEither(head, (x) -> count.getAndIncrement()); + } + head.complete(null); + assertEquals(5 * 3 * n, count.get()); + } + +// static U join(CompletionStage stage) { +// CompletableFuture f = new CompletableFuture<>(); +// stage.whenComplete((v, ex) -> { +// if (ex != null) f.completeExceptionally(ex); else f.complete(v); +// }); +// return f.join(); +// } + +// static boolean isDone(CompletionStage stage) { +// CompletableFuture f = new CompletableFuture<>(); +// stage.whenComplete((v, ex) -> { +// if (ex != null) f.completeExceptionally(ex); else f.complete(v); +// }); +// return f.isDone(); +// } + +// static U join2(CompletionStage stage) { +// return stage.toCompletableFuture().copy().join(); +// } + +// static boolean isDone2(CompletionStage stage) { +// return stage.toCompletableFuture().copy().isDone(); +// } + }