java.util.concurrent.CompletableFuture#thenAcceptBoth ( )源码实例Demo

/**
 * When an already-contextualized Supplier or BiFunction is specified as the action/task,
 * the action/task runs with its already-captured context rather than
 * capturing and applying context per the configuration of the managed executor.
 *
 * @throws ExecutionException indicates test failure
 * @throws InterruptedException indicates test failure
 * @throws TimeoutException indicates test failure
 */
@Test
public void contextOfContextualSuppplierAndBiConsumerOverrideContextOfManagedExecutor()
        throws ExecutionException, InterruptedException, TimeoutException {
    ThreadContext bufferContext = ThreadContext.builder()
            .propagated(Buffer.CONTEXT_NAME)
            .unchanged()
            .cleared(ThreadContext.ALL_REMAINING)
            .build();

    ManagedExecutor executor = ManagedExecutor.builder()
            .propagated(Label.CONTEXT_NAME)
            .cleared(ThreadContext.ALL_REMAINING)
            .build();
    try {
        Supplier<String> getBuffer = () -> {
            Assert.assertEquals(Label.get(), "",
                    "Context type not cleared from thread.");
            return Buffer.get().toString();
        };

        Buffer.set(new StringBuffer("contextualSupplierOverride-buffer-1"));
        Label.set("contextualSupplierOverride-label-1");

        Supplier<String> precontextualizedSupplier1 = bufferContext.contextualSupplier(getBuffer);

        Buffer.set(new StringBuffer("contextualSupplierOverride-buffer-2"));
        Label.set("contextualSupplierOverride-label-2");

        Supplier<String> precontextualizedSupplier2 = bufferContext.contextualSupplier(getBuffer);

        Buffer.set(new StringBuffer("contextualBiConsumerOverride-buffer-3"));
        Label.set("contextualBiConsumerOverride-label-3");

        BiConsumer<String, String> precontextualizedConsumer3 = bufferContext.contextualConsumer((b1, b2) -> {
            Assert.assertEquals(Buffer.get().toString(), "contextualBiConsumerOverride-buffer-3",
                    "Previously captured context type not found on thread.");
            Assert.assertEquals(Label.get(), "",
                    "Context type not cleared from thread.");

            Assert.assertEquals(b1, "contextualSupplierOverride-buffer-1",
                    "Previously captured context type not found on Supplier's thread.");

            Assert.assertEquals(b2, "contextualSupplierOverride-buffer-2",
                    "Previously captured context type not found on Supplier's thread.");
        });

        Buffer.set(new StringBuffer("contextualBiConsumerOverride-buffer-4"));
        Label.set("contextualBiConsumerOverride-label-4");

        BiConsumer<Void, Throwable> precontextualizedConsumer4 = bufferContext.contextualConsumer((unused, failure) -> {
            Assert.assertEquals(Buffer.get().toString(), "contextualBiConsumerOverride-buffer-4",
                    "Previously captured context type not found on thread.");
            Assert.assertEquals(Label.get(), "",
                    "Context type not cleared from thread.");
        });

        Buffer.set(new StringBuffer("contextualSupplierAndBiConsumerOverride-buffer-5"));
        Label.set("contextualSupplierAndBiConsumerOverride-label-5");

        CompletableFuture<String> stage1 = executor.supplyAsync(precontextualizedSupplier1);
        CompletableFuture<String> stage2 = executor.supplyAsync(precontextualizedSupplier2);
        CompletableFuture<Void> stage3 = stage1.thenAcceptBoth(stage2, precontextualizedConsumer3);
        CompletableFuture<Void> stage4 = stage3.whenCompleteAsync(precontextualizedConsumer4);
        CompletableFuture<Void> stage5 = stage4.whenComplete((unused, failure) -> {
            Assert.assertEquals(Label.get(), "contextualSupplierAndBiConsumerOverride-label-5",
                    "Context type captured by managed executor not found on thread.");
            Assert.assertEquals(Buffer.get().toString(), "",
                    "Context type not cleared from thread.");
        });

        stage5.join();
    }
    finally {
        executor.shutdownNow();
        // Restore original values
        Buffer.set(null);
        Label.set(null);
    }
}
 

public <T,U> CompletableFuture<Void> thenAcceptBoth
    (CompletableFuture<T> f,
     CompletionStage<? extends U> g,
     BiConsumer<? super T,? super U> a) {
    return f.thenAcceptBoth(g, a);
}
 

public static void main(String[] args) throws Exception {
   DefaultCacheManager cacheManager = new DefaultCacheManager();
   cacheManager.defineConfiguration("local", new ConfigurationBuilder().build());
   AdvancedCache<String, String> cache = cacheManager.<String, String>getCache("local").getAdvancedCache();
   FunctionalMapImpl<String, String> functionalMap = FunctionalMapImpl.create(cache);
   FunctionalMap.WriteOnlyMap<String, String> writeOnlyMap = WriteOnlyMapImpl.create(functionalMap);
   FunctionalMap.ReadOnlyMap<String, String> readOnlyMap = ReadOnlyMapImpl.create(functionalMap);

   // Execute two parallel write-only operation to store key/value pairs
   CompletableFuture<Void> writeFuture1 = writeOnlyMap.eval("key1", "value1",
      (v, writeView) -> writeView.set(v));
   CompletableFuture<Void> writeFuture2 = writeOnlyMap.eval("key2", "value2",
      (v, writeView) -> writeView.set(v));

   // When each write-only operation completes, execute a read-only operation to retrieve the value
   CompletableFuture<String> readFuture1 =
      writeFuture1.thenCompose(r -> readOnlyMap.eval("key1", EntryView.ReadEntryView::get));
   CompletableFuture<String> readFuture2 =
      writeFuture2.thenCompose(r -> readOnlyMap.eval("key2", EntryView.ReadEntryView::get));

   // When the read-only operation completes, print it out
   System.out.printf("Created entries: %n");
   CompletableFuture<Void> end = readFuture1.thenAcceptBoth(readFuture2, (v1, v2) ->
      System.out.printf("key1 = %s%nkey2 = %s%n", v1, v2));

   // Wait for this read/write combination to finish
   end.get();

   // Create a read-write map
   FunctionalMap.ReadWriteMap<String, String> readWriteMap = ReadWriteMapImpl.create(functionalMap);

   // Use read-write multi-key based operation to write new values
   // together with lifespan and return previous values
   Map<String, String> data = new HashMap<>();
   data.put("key1", "newValue1");
   data.put("key2", "newValue2");
   Traversable<String> previousValues = readWriteMap.evalMany(data, (v, readWriteView) -> {
      String prev = readWriteView.find().orElse(null);
      readWriteView.set(v, new MetaLifespan(Duration.ofHours(1).toMillis()));
      return prev;
   });

   // Use read-only multi-key operation to read current values for multiple keys
   Traversable<EntryView.ReadEntryView<String, String>> entryViews =
      readOnlyMap.evalMany(data.keySet(), readOnlyView -> readOnlyView);
   System.out.printf("Updated entries: %n");
   entryViews.forEach(view -> System.out.printf("%s%n", view));

   // Finally, print out the previous entry values
   System.out.printf("Previous entry values: %n");
   previousValues.forEach(prev -> System.out.printf("%s%n", prev));
}
 

public <T,U> CompletableFuture<Void> thenAcceptBoth
    (CompletableFuture<T> f,
     CompletionStage<? extends U> g,
     BiConsumer<? super T,? super U> a) {
    return f.thenAcceptBoth(g, a);
}