--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.incubator.httpclient/share/classes/jdk/incubator/http/ResponseSubscribers.java Wed Dec 06 11:11:59 2017 -0800
@@ -0,0 +1,561 @@
+/*
+ * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.incubator.http;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.lang.System.Logger.Level;
+import java.nio.ByteBuffer;
+import java.nio.channels.FileChannel;
+import java.nio.file.OpenOption;
+import java.nio.file.Path;
+import java.security.AccessControlContext;
+import java.security.AccessController;
+import java.security.PrivilegedActionException;
+import java.security.PrivilegedExceptionAction;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Flow;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import jdk.incubator.http.internal.common.MinimalFuture;
+import jdk.incubator.http.internal.common.Utils;
+
+class ResponseSubscribers {
+
+ static class ConsumerSubscriber implements HttpResponse.BodySubscriber<Void> {
+ private final Consumer<Optional<byte[]>> consumer;
+ private Flow.Subscription subscription;
+ private final CompletableFuture<Void> result = new MinimalFuture<>();
+ private final AtomicBoolean subscribed = new AtomicBoolean();
+
+ ConsumerSubscriber(Consumer<Optional<byte[]>> consumer) {
+ this.consumer = consumer;
+ }
+
+ @Override
+ public CompletionStage<Void> getBody() {
+ return result;
+ }
+
+ @Override
+ public void onSubscribe(Flow.Subscription subscription) {
+ if (!subscribed.compareAndSet(false, true)) {
+ subscription.cancel();
+ } else {
+ this.subscription = subscription;
+ subscription.request(1);
+ }
+ }
+
+ @Override
+ public void onNext(List<ByteBuffer> items) {
+ for (ByteBuffer item : items) {
+ byte[] buf = new byte[item.remaining()];
+ item.get(buf);
+ consumer.accept(Optional.of(buf));
+ }
+ subscription.request(1);
+ }
+
+ @Override
+ public void onError(Throwable throwable) {
+ result.completeExceptionally(throwable);
+ }
+
+ @Override
+ public void onComplete() {
+ consumer.accept(Optional.empty());
+ result.complete(null);
+ }
+
+ }
+
+ static class PathSubscriber implements HttpResponse.BodySubscriber<Path> {
+
+ private final Path file;
+ private final CompletableFuture<Path> result = new MinimalFuture<>();
+
+ private volatile Flow.Subscription subscription;
+ private volatile FileChannel out;
+ private volatile AccessControlContext acc;
+ private final OpenOption[] options;
+
+ PathSubscriber(Path file, OpenOption... options) {
+ this.file = file;
+ this.options = options;
+ }
+
+ void setAccessControlContext(AccessControlContext acc) {
+ this.acc = acc;
+ }
+
+ @Override
+ public void onSubscribe(Flow.Subscription subscription) {
+ if (System.getSecurityManager() != null && acc == null)
+ throw new InternalError(
+ "Unexpected null acc when security manager has been installed");
+
+ this.subscription = subscription;
+ try {
+ PrivilegedExceptionAction<FileChannel> pa =
+ () -> FileChannel.open(file, options);
+ out = AccessController.doPrivileged(pa, acc);
+ } catch (PrivilegedActionException pae) {
+ Throwable t = pae.getCause() != null ? pae.getCause() : pae;
+ result.completeExceptionally(t);
+ subscription.cancel();
+ return;
+ }
+ subscription.request(1);
+ }
+
+ @Override
+ public void onNext(List<ByteBuffer> items) {
+ try {
+ out.write(items.toArray(Utils.EMPTY_BB_ARRAY));
+ } catch (IOException ex) {
+ Utils.close(out);
+ subscription.cancel();
+ result.completeExceptionally(ex);
+ }
+ subscription.request(1);
+ }
+
+ @Override
+ public void onError(Throwable e) {
+ result.completeExceptionally(e);
+ Utils.close(out);
+ }
+
+ @Override
+ public void onComplete() {
+ Utils.close(out);
+ result.complete(file);
+ }
+
+ @Override
+ public CompletionStage<Path> getBody() {
+ return result;
+ }
+ }
+
+ static class ByteArraySubscriber<T> implements HttpResponse.BodySubscriber<T> {
+ private final Function<byte[], T> finisher;
+ private final CompletableFuture<T> result = new MinimalFuture<>();
+ private final List<ByteBuffer> received = new ArrayList<>();
+
+ private volatile Flow.Subscription subscription;
+
+ ByteArraySubscriber(Function<byte[],T> finisher) {
+ this.finisher = finisher;
+ }
+
+ @Override
+ public void onSubscribe(Flow.Subscription subscription) {
+ if (this.subscription != null) {
+ subscription.cancel();
+ return;
+ }
+ this.subscription = subscription;
+ // We can handle whatever you've got
+ subscription.request(Long.MAX_VALUE);
+ }
+
+ @Override
+ public void onNext(List<ByteBuffer> items) {
+ // incoming buffers are allocated by http client internally,
+ // and won't be used anywhere except this place.
+ // So it's free simply to store them for further processing.
+ assert Utils.hasRemaining(items);
+ Utils.accumulateBuffers(received, items);
+ }
+
+ @Override
+ public void onError(Throwable throwable) {
+ received.clear();
+ result.completeExceptionally(throwable);
+ }
+
+ static private byte[] join(List<ByteBuffer> bytes) {
+ int size = Utils.remaining(bytes, Integer.MAX_VALUE);
+ byte[] res = new byte[size];
+ int from = 0;
+ for (ByteBuffer b : bytes) {
+ int l = b.remaining();
+ b.get(res, from, l);
+ from += l;
+ }
+ return res;
+ }
+
+ @Override
+ public void onComplete() {
+ try {
+ result.complete(finisher.apply(join(received)));
+ received.clear();
+ } catch (IllegalArgumentException e) {
+ result.completeExceptionally(e);
+ }
+ }
+
+ @Override
+ public CompletionStage<T> getBody() {
+ return result;
+ }
+ }
+
+ /**
+ * An InputStream built on top of the Flow API.
+ */
+ static class HttpResponseInputStream extends InputStream
+ implements HttpResponse.BodySubscriber<InputStream>
+ {
+ final static boolean DEBUG = Utils.DEBUG;
+ final static int MAX_BUFFERS_IN_QUEUE = 1; // lock-step with the producer
+
+ // An immutable ByteBuffer sentinel to mark that the last byte was received.
+ private static final ByteBuffer LAST_BUFFER = ByteBuffer.wrap(new byte[0]);
+ private static final List<ByteBuffer> LAST_LIST = List.of(LAST_BUFFER);
+ private static final System.Logger DEBUG_LOGGER =
+ Utils.getDebugLogger("HttpResponseInputStream"::toString, DEBUG);
+
+ // A queue of yet unprocessed ByteBuffers received from the flow API.
+ private final BlockingQueue<List<ByteBuffer>> buffers;
+ private volatile Flow.Subscription subscription;
+ private volatile boolean closed;
+ private volatile Throwable failed;
+ private volatile Iterator<ByteBuffer> currentListItr;
+ private volatile ByteBuffer currentBuffer;
+ private final AtomicBoolean subscribed = new AtomicBoolean();
+
+ HttpResponseInputStream() {
+ this(MAX_BUFFERS_IN_QUEUE);
+ }
+
+ HttpResponseInputStream(int maxBuffers) {
+ int capacity = (maxBuffers <= 0 ? MAX_BUFFERS_IN_QUEUE : maxBuffers);
+ // 1 additional slot needed for LAST_LIST added by onComplete
+ this.buffers = new ArrayBlockingQueue<>(capacity + 1);
+ }
+
+ @Override
+ public CompletionStage<InputStream> getBody() {
+ // Returns the stream immediately, before the
+ // response body is received.
+ // This makes it possible for senAsync().get().body()
+ // to complete before the response body is received.
+ return CompletableFuture.completedStage(this);
+ }
+
+ // Returns the current byte buffer to read from.
+ // If the current buffer has no remaining data, this method will take the
+ // next buffer from the buffers queue, possibly blocking until
+ // a new buffer is made available through the Flow API, or the
+ // end of the flow has been reached.
+ private ByteBuffer current() throws IOException {
+ while (currentBuffer == null || !currentBuffer.hasRemaining()) {
+ // Check whether the stream is closed or exhausted
+ if (closed || failed != null) {
+ throw new IOException("closed", failed);
+ }
+ if (currentBuffer == LAST_BUFFER) break;
+
+ try {
+ if (currentListItr == null || !currentListItr.hasNext()) {
+ // Take a new list of buffers from the queue, blocking
+ // if none is available yet...
+
+ DEBUG_LOGGER.log(Level.DEBUG, "Taking list of Buffers");
+ List<ByteBuffer> lb = buffers.take();
+ currentListItr = lb.iterator();
+ DEBUG_LOGGER.log(Level.DEBUG, "List of Buffers Taken");
+
+ // Check whether an exception was encountered upstream
+ if (closed || failed != null)
+ throw new IOException("closed", failed);
+
+ // Check whether we're done.
+ if (lb == LAST_LIST) {
+ currentListItr = null;
+ currentBuffer = LAST_BUFFER;
+ break;
+ }
+
+ // Request another upstream item ( list of buffers )
+ Flow.Subscription s = subscription;
+ if (s != null) {
+ DEBUG_LOGGER.log(Level.DEBUG, "Increased demand by 1");
+ s.request(1);
+ }
+ assert currentListItr != null;
+ if (lb.isEmpty()) continue;
+ }
+ assert currentListItr != null;
+ assert currentListItr.hasNext();
+ DEBUG_LOGGER.log(Level.DEBUG, "Next Buffer");
+ currentBuffer = currentListItr.next();
+ } catch (InterruptedException ex) {
+ // continue
+ }
+ }
+ assert currentBuffer == LAST_BUFFER || currentBuffer.hasRemaining();
+ return currentBuffer;
+ }
+
+ @Override
+ public int read(byte[] bytes, int off, int len) throws IOException {
+ // get the buffer to read from, possibly blocking if
+ // none is available
+ ByteBuffer buffer;
+ if ((buffer = current()) == LAST_BUFFER) return -1;
+
+ // don't attempt to read more than what is available
+ // in the current buffer.
+ int read = Math.min(buffer.remaining(), len);
+ assert read > 0 && read <= buffer.remaining();
+
+ // buffer.get() will do the boundary check for us.
+ buffer.get(bytes, off, read);
+ return read;
+ }
+
+ @Override
+ public int read() throws IOException {
+ ByteBuffer buffer;
+ if ((buffer = current()) == LAST_BUFFER) return -1;
+ return buffer.get() & 0xFF;
+ }
+
+ @Override
+ public void onSubscribe(Flow.Subscription s) {
+ try {
+ if (!subscribed.compareAndSet(false, true)) {
+ s.cancel();
+ } else {
+ // check whether the stream is already closed.
+ // if so, we should cancel the subscription
+ // immediately.
+ boolean closed;
+ synchronized (this) {
+ closed = this.closed;
+ if (!closed) {
+ this.subscription = s;
+ }
+ }
+ if (closed) {
+ s.cancel();
+ return;
+ }
+ assert buffers.remainingCapacity() > 1; // should contain at least 2
+ DEBUG_LOGGER.log(Level.DEBUG, () -> "onSubscribe: requesting "
+ + Math.max(1, buffers.remainingCapacity() - 1));
+ s.request(Math.max(1, buffers.remainingCapacity() - 1));
+ }
+ } catch (Throwable t) {
+ failed = t;
+ try {
+ close();
+ } catch (IOException x) {
+ // OK
+ } finally {
+ onError(t);
+ }
+ }
+ }
+
+ @Override
+ public void onNext(List<ByteBuffer> t) {
+ Objects.requireNonNull(t);
+ try {
+ DEBUG_LOGGER.log(Level.DEBUG, "next item received");
+ if (!buffers.offer(t)) {
+ throw new IllegalStateException("queue is full");
+ }
+ DEBUG_LOGGER.log(Level.DEBUG, "item offered");
+ } catch (Throwable ex) {
+ failed = ex;
+ try {
+ close();
+ } catch (IOException ex1) {
+ // OK
+ } finally {
+ onError(ex);
+ }
+ }
+ }
+
+ @Override
+ public void onError(Throwable thrwbl) {
+ subscription = null;
+ failed = Objects.requireNonNull(thrwbl);
+ // The client process that reads the input stream might
+ // be blocked in queue.take().
+ // Tries to offer LAST_LIST to the queue. If the queue is
+ // full we don't care if we can't insert this buffer, as
+ // the client can't be blocked in queue.take() in that case.
+ // Adding LAST_LIST to the queue is harmless, as the client
+ // should find failed != null before handling LAST_LIST.
+ buffers.offer(LAST_LIST);
+ }
+
+ @Override
+ public void onComplete() {
+ subscription = null;
+ onNext(LAST_LIST);
+ }
+
+ @Override
+ public void close() throws IOException {
+ Flow.Subscription s;
+ synchronized (this) {
+ if (closed) return;
+ closed = true;
+ s = subscription;
+ subscription = null;
+ }
+ // s will be null if already completed
+ try {
+ if (s != null) {
+ s.cancel();
+ }
+ } finally {
+ buffers.offer(LAST_LIST);
+ super.close();
+ }
+ }
+
+ }
+
+ static class MultiSubscriberImpl<V>
+ implements HttpResponse.MultiSubscriber<MultiMapResult<V>,V>
+ {
+ private final MultiMapResult<V> results;
+ private final Function<HttpRequest,Optional<HttpResponse.BodyHandler<V>>> pushHandler;
+ private final Function<HttpRequest,HttpResponse.BodyHandler<V>> requestHandler;
+ private final boolean completion; // aggregate completes on last PP received or overall completion
+
+ MultiSubscriberImpl(
+ Function<HttpRequest,HttpResponse.BodyHandler<V>> requestHandler,
+ Function<HttpRequest,Optional<HttpResponse.BodyHandler<V>>> pushHandler, boolean completion) {
+ this.results = new MultiMapResult<>(new ConcurrentHashMap<>());
+ this.requestHandler = requestHandler;
+ this.pushHandler = pushHandler;
+ this.completion = completion;
+ }
+
+ @Override
+ public HttpResponse.BodyHandler<V> onRequest(HttpRequest request) {
+ CompletableFuture<HttpResponse<V>> cf = MinimalFuture.newMinimalFuture();
+ results.put(request, cf);
+ return requestHandler.apply(request);
+ }
+
+ @Override
+ public Optional<HttpResponse.BodyHandler<V>> onPushPromise(HttpRequest push) {
+ CompletableFuture<HttpResponse<V>> cf = MinimalFuture.newMinimalFuture();
+ results.put(push, cf);
+ return pushHandler.apply(push);
+ }
+
+ @Override
+ public void onResponse(HttpResponse<V> response) {
+ CompletableFuture<HttpResponse<V>> cf = results.get(response.request());
+ cf.complete(response);
+ }
+
+ @Override
+ public void onError(HttpRequest request, Throwable t) {
+ CompletableFuture<HttpResponse<V>> cf = results.get(request);
+ cf.completeExceptionally(t);
+ }
+
+ @Override
+ public CompletableFuture<MultiMapResult<V>> completion(
+ CompletableFuture<Void> onComplete, CompletableFuture<Void> onFinalPushPromise) {
+ if (completion)
+ return onComplete.thenApply((ignored)-> results);
+ else
+ return onFinalPushPromise.thenApply((ignored) -> results);
+ }
+ }
+
+ /**
+ * Currently this consumes all of the data and ignores it
+ */
+ static class NullSubscriber<T> implements HttpResponse.BodySubscriber<T> {
+
+ private final CompletableFuture<T> cf = new MinimalFuture<>();
+ private final Optional<T> result;
+ private final AtomicBoolean subscribed = new AtomicBoolean();
+
+ NullSubscriber(Optional<T> result) {
+ this.result = result;
+ }
+
+ @Override
+ public void onSubscribe(Flow.Subscription subscription) {
+ if (!subscribed.compareAndSet(false, true)) {
+ subscription.cancel();
+ } else {
+ subscription.request(Long.MAX_VALUE);
+ }
+ }
+
+ @Override
+ public void onNext(List<ByteBuffer> items) {
+ Objects.requireNonNull(items);
+ }
+
+ @Override
+ public void onError(Throwable throwable) {
+ cf.completeExceptionally(throwable);
+ }
+
+ @Override
+ public void onComplete() {
+ if (result.isPresent()) {
+ cf.complete(result.get());
+ } else {
+ cf.complete(null);
+ }
+ }
+
+ @Override
+ public CompletionStage<T> getBody() {
+ return cf;
+ }
+ }
+}