src/jdk.incubator.httpclient/share/classes/jdk/incubator/http/internal/ResponseSubscribers.java
branchhttp-client-branch
changeset 56089 42208b2f224e
parent 56088 38fac6d0521d
child 56090 5c7fb702948a
--- a/src/jdk.incubator.httpclient/share/classes/jdk/incubator/http/internal/ResponseSubscribers.java	Tue Feb 06 19:37:56 2018 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,650 +0,0 @@
-/*
- * Copyright (c) 2016, 2018, 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.internal;
-
-import java.io.BufferedReader;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.lang.System.Logger.Level;
-import java.nio.ByteBuffer;
-import java.nio.channels.FileChannel;
-import java.nio.charset.Charset;
-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.Executor;
-import java.util.concurrent.Flow;
-import java.util.concurrent.Flow.Subscriber;
-import java.util.concurrent.Flow.Subscription;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.function.Consumer;
-import java.util.function.Function;
-import java.util.stream.Stream;
-import jdk.incubator.http.HttpResponse.BodySubscriber;
-import jdk.incubator.http.internal.common.MinimalFuture;
-import jdk.incubator.http.internal.common.Utils;
-import static java.nio.charset.StandardCharsets.UTF_8;
-
-public class ResponseSubscribers {
-
-    public static class ConsumerSubscriber implements 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();
-
-        public ConsumerSubscriber(Consumer<Optional<byte[]>> consumer) {
-            this.consumer = Objects.requireNonNull(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);
-        }
-
-    }
-
-    public static class PathSubscriber implements 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;
-
-        public PathSubscriber(Path file, OpenOption... options) {
-            this.file = file;
-            this.options = options;
-        }
-
-        public 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;
-        }
-    }
-
-    public static class ByteArraySubscriber<T> implements 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;
-
-        public 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);
-            received.addAll(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.
-     */
-    public static class HttpResponseInputStream extends InputStream
-        implements 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();
-
-        public 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 sendAsync().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();
-            }
-        }
-
-    }
-
-    public static BodySubscriber<Stream<String>> createLineStream() {
-        return createLineStream(UTF_8);
-    }
-
-    public static BodySubscriber<Stream<String>> createLineStream(Charset charset) {
-        Objects.requireNonNull(charset);
-        BodySubscriber<InputStream> s = new HttpResponseInputStream();
-        return new MappedSubscriber<InputStream,Stream<String>>(s,
-            (InputStream stream) -> {
-                return new BufferedReader(new InputStreamReader(stream, charset))
-                            .lines().onClose(() -> Utils.close(stream));
-            });
-    }
-
-    /**
-     * Currently this consumes all of the data and ignores it
-     */
-    public static class NullSubscriber<T> implements BodySubscriber<T> {
-
-        private final CompletableFuture<T> cf = new MinimalFuture<>();
-        private final Optional<T> result;
-        private final AtomicBoolean subscribed = new AtomicBoolean();
-
-        public 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;
-        }
-    }
-
-    /** An adapter between {@code BodySubscriber} and {@code Flow.Subscriber}. */
-    public static final class SubscriberAdapter<S extends Subscriber<? super List<ByteBuffer>>,R>
-        implements BodySubscriber<R>
-    {
-        private final CompletableFuture<R> cf = new MinimalFuture<>();
-        private final S subscriber;
-        private final Function<S,R> finisher;
-        private volatile Subscription subscription;
-
-        public SubscriberAdapter(S subscriber, Function<S,R> finisher) {
-            this.subscriber = Objects.requireNonNull(subscriber);
-            this.finisher = Objects.requireNonNull(finisher);
-        }
-
-        @Override
-        public void onSubscribe(Subscription subscription) {
-            Objects.requireNonNull(subscription);
-            if (this.subscription != null) {
-                subscription.cancel();
-            } else {
-                this.subscription = subscription;
-                subscriber.onSubscribe(subscription);
-            }
-        }
-
-        @Override
-        public void onNext(List<ByteBuffer> item) {
-            Objects.requireNonNull(item);
-            try {
-                subscriber.onNext(item);
-            } catch (Throwable throwable) {
-                subscription.cancel();
-                onError(throwable);
-            }
-        }
-
-        @Override
-        public void onError(Throwable throwable) {
-            Objects.requireNonNull(throwable);
-            try {
-                subscriber.onError(throwable);
-            } finally {
-                cf.completeExceptionally(throwable);
-            }
-        }
-
-        @Override
-        public void onComplete() {
-            try {
-                subscriber.onComplete();
-            } finally {
-                try {
-                    cf.complete(finisher.apply(subscriber));
-                } catch (Throwable throwable) {
-                    cf.completeExceptionally(throwable);
-                }
-            }
-        }
-
-        @Override
-        public CompletionStage<R> getBody() {
-            return cf;
-        }
-    }
-
-    /**
-     * A body subscriber which receives input from an upstream subscriber
-     * and maps that subscriber's body type to a new type. The upstream subscriber
-     * delegates all flow operations directly to this object. The
-     * {@link CompletionStage} returned by {@link #getBody()}} takes the output
-     * of the upstream {@code getBody()} and applies the mapper function to
-     * obtain the new {@code CompletionStage} type.
-     *
-     * Uses an Executor that must be set externally.
-     *
-     * @param <T> the upstream body type
-     * @param <U> this subscriber's body type
-     */
-    public static class MappedSubscriber<T,U> implements BodySubscriber<U> {
-        final BodySubscriber<T> upstream;
-        final Function<T,U> mapper;
-
-        /**
-         *
-         * @param upstream
-         * @param mapper
-         */
-        public MappedSubscriber(BodySubscriber<T> upstream, Function<T,U> mapper) {
-            this.upstream = upstream;
-            this.mapper = mapper;
-        }
-
-        @Override
-        public CompletionStage<U> getBody() {
-            return upstream.getBody()
-                    .thenApply(mapper);
-        }
-
-        @Override
-        public void onSubscribe(Flow.Subscription subscription) {
-            upstream.onSubscribe(subscription);
-        }
-
-        @Override
-        public void onNext(List<ByteBuffer> item) {
-            upstream.onNext(item);
-        }
-
-        @Override
-        public void onError(Throwable throwable) {
-            upstream.onError(throwable);
-        }
-
-        @Override
-        public void onComplete() {
-            upstream.onComplete();
-        }
-    }
-}