--- a/src/jdk.incubator.httpclient/share/classes/jdk/incubator/http/LineSubscriberAdapter.java Tue Feb 06 11:15:40 2018 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,467 +0,0 @@
-/*
- * Copyright (c) 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;
-
-import java.nio.ByteBuffer;
-import java.nio.CharBuffer;
-import java.nio.charset.CharacterCodingException;
-import java.nio.charset.Charset;
-import java.nio.charset.CharsetDecoder;
-import java.nio.charset.CoderResult;
-import java.nio.charset.CodingErrorAction;
-import java.util.List;
-import java.util.Objects;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.CompletionStage;
-import java.util.concurrent.ConcurrentLinkedDeque;
-import java.util.concurrent.Flow;
-import java.util.concurrent.Flow.Subscriber;
-import java.util.concurrent.Flow.Subscription;
-import java.util.concurrent.atomic.AtomicLong;
-import java.util.concurrent.atomic.AtomicReference;
-import java.util.function.Function;
-
-import jdk.incubator.http.internal.common.Demand;
-import jdk.incubator.http.internal.common.MinimalFuture;
-import jdk.incubator.http.internal.common.SequentialScheduler;
-
-/** An adapter between {@code BodySubscriber} and {@code Flow.Subscriber<String>}. */
-final class LineSubscriberAdapter<S extends Subscriber<? super String>,R>
- implements HttpResponse.BodySubscriber<R> {
- private final CompletableFuture<R> cf = new MinimalFuture<>();
- private final S subscriber;
- private final Function<S, R> finisher;
- private final Charset charset;
- private final String eol;
- private volatile LineSubscription downstream;
-
- private LineSubscriberAdapter(S subscriber,
- Function<S, R> finisher,
- Charset charset,
- String eol) {
- if (eol != null && eol.isEmpty())
- throw new IllegalArgumentException("empty line separator");
- this.subscriber = Objects.requireNonNull(subscriber);
- this.finisher = Objects.requireNonNull(finisher);
- this.charset = Objects.requireNonNull(charset);
- this.eol = eol;
- }
-
- @Override
- public void onSubscribe(Subscription subscription) {
- downstream = LineSubscription.create(subscription,
- charset,
- eol,
- subscriber,
- cf);
- subscriber.onSubscribe(downstream);
- }
-
- @Override
- public void onNext(List<ByteBuffer> item) {
- try {
- downstream.submit(item);
- } catch (Throwable t) {
- onError(t);
- }
- }
-
- @Override
- public void onError(Throwable throwable) {
- try {
- downstream.signalError(throwable);
- } finally {
- cf.completeExceptionally(throwable);
- }
- }
-
- @Override
- public void onComplete() {
- try {
- downstream.signalComplete();
- } finally {
- cf.complete(finisher.apply(subscriber));
- }
- }
-
- @Override
- public CompletionStage<R> getBody() {
- return cf;
- }
-
- static <S extends Subscriber<? super String>, R> LineSubscriberAdapter<S, R>
- create(S subscriber, Function<S, R> finisher, Charset charset, String eol)
- {
- if (eol != null && eol.isEmpty())
- throw new IllegalArgumentException("empty line separator");
- return new LineSubscriberAdapter<>(Objects.requireNonNull(subscriber),
- Objects.requireNonNull(finisher),
- Objects.requireNonNull(charset),
- eol);
- }
-
- static final class LineSubscription implements Flow.Subscription {
- final Flow.Subscription upstreamSubscription;
- final CharsetDecoder decoder;
- final String newline;
- final Demand downstreamDemand;
- final ConcurrentLinkedDeque<ByteBuffer> queue;
- final SequentialScheduler scheduler;
- final Flow.Subscriber<? super String> upstream;
- final CompletableFuture<?> cf;
- private final AtomicReference<Throwable> errorRef = new AtomicReference<>();
- private final AtomicLong demanded = new AtomicLong();
- private volatile boolean completed;
- private volatile boolean cancelled;
-
- private final char[] chars = new char[1024];
- private final ByteBuffer leftover = ByteBuffer.wrap(new byte[64]);
- private final CharBuffer buffer = CharBuffer.wrap(chars);
- private final StringBuilder builder = new StringBuilder();
- private int lineCount;
- private String nextLine;
-
- private LineSubscription(Flow.Subscription s,
- CharsetDecoder dec,
- String separator,
- Flow.Subscriber<? super String> subscriber,
- CompletableFuture<?> completion) {
- downstreamDemand = new Demand();
- queue = new ConcurrentLinkedDeque<>();
- upstreamSubscription = Objects.requireNonNull(s);
- decoder = Objects.requireNonNull(dec);
- newline = separator;
- upstream = Objects.requireNonNull(subscriber);
- cf = Objects.requireNonNull(completion);
- scheduler = SequentialScheduler.synchronizedScheduler(this::loop);
- }
-
- @Override
- public void request(long n) {
- if (cancelled) return;
- if (downstreamDemand.increase(n)) {
- scheduler.runOrSchedule();
- }
- }
-
- @Override
- public void cancel() {
- cancelled = true;
- upstreamSubscription.cancel();
- }
-
- public void submit(List<ByteBuffer> list) {
- queue.addAll(list);
- demanded.decrementAndGet();
- scheduler.runOrSchedule();
- }
-
- public void signalComplete() {
- completed = true;
- scheduler.runOrSchedule();
- }
-
- public void signalError(Throwable error) {
- if (errorRef.compareAndSet(null,
- Objects.requireNonNull(error))) {
- scheduler.runOrSchedule();
- }
- }
-
- // This method looks at whether some bytes where left over (in leftover)
- // from decoding the previous buffer when the previous buffer was in
- // underflow. If so, it takes bytes one by one from the new buffer 'in'
- // and combines them with the leftover bytes until 'in' is exhausted or a
- // character was produced in 'out', resolving the previous underflow.
- // Returns true if the buffer is still in underflow, false otherwise.
- // However, in both situation some chars might have been produced in 'out'.
- private boolean isUnderFlow(ByteBuffer in, CharBuffer out, boolean endOfInput)
- throws CharacterCodingException {
- int limit = leftover.position();
- if (limit == 0) {
- // no leftover
- return false;
- } else {
- CoderResult res = null;
- while (in.hasRemaining()) {
- leftover.position(limit);
- leftover.limit(++limit);
- leftover.put(in.get());
- leftover.position(0);
- res = decoder.decode(leftover, out,
- endOfInput && !in.hasRemaining());
- int remaining = leftover.remaining();
- if (remaining > 0) {
- assert leftover.position() == 0;
- leftover.position(remaining);
- } else {
- leftover.position(0);
- }
- leftover.limit(leftover.capacity());
- if (res.isUnderflow() && remaining > 0 && in.hasRemaining()) {
- continue;
- }
- if (res.isError()) {
- res.throwException();
- }
- assert !res.isOverflow();
- return false;
- }
- return !endOfInput;
- }
- }
-
- // extract characters from start to end and remove them from
- // the StringBuilder
- private static String take(StringBuilder b, int start, int end) {
- assert start == 0;
- String line;
- if (end == start) return "";
- line = b.substring(start, end);
- b.delete(start, end);
- return line;
- }
-
- // finds end of line, returns -1 if not found, or the position after
- // the line delimiter if found, removing the delimiter in the process.
- private static int endOfLine(StringBuilder b, String eol, boolean endOfInput) {
- int len = b.length();
- if (eol != null) { // delimiter explicitly specified
- int i = b.indexOf(eol);
- if (i >= 0) {
- // remove the delimiter and returns the position
- // of the char after it.
- b.delete(i, i + eol.length());
- return i;
- }
- } else { // no delimiter specified, behaves as BufferedReader::readLine
- boolean crfound = false;
- for (int i = 0; i < len; i++) {
- char c = b.charAt(i);
- if (c == '\n') {
- // '\n' or '\r\n' found.
- // remove the delimiter and returns the position
- // of the char after it.
- b.delete(crfound ? i - 1 : i, i + 1);
- return crfound ? i - 1 : i;
- } else if (crfound) {
- // previous char was '\r', c != '\n'
- assert i != 0;
- // remove the delimiter and returns the position
- // of the char after it.
- b.delete(i - 1, i);
- return i - 1;
- }
- crfound = c == '\r';
- }
- if (crfound && endOfInput) {
- // remove the delimiter and returns the position
- // of the char after it.
- b.delete(len - 1, len);
- return len - 1;
- }
- }
- return endOfInput && len > 0 ? len : -1;
- }
-
- // Looks at whether the StringBuilder contains a line.
- // Returns null if more character are needed.
- private static String nextLine(StringBuilder b, String eol, boolean endOfInput) {
- int next = endOfLine(b, eol, endOfInput);
- return (next > -1) ? take(b, 0, next) : null;
- }
-
- // Attempts to read the next line. Returns the next line if
- // the delimiter was found, null otherwise. The delimiters are
- // consumed.
- private String nextLine()
- throws CharacterCodingException {
- assert nextLine == null;
- LINES:
- while (nextLine == null) {
- boolean endOfInput = completed && queue.isEmpty();
- nextLine = nextLine(builder, newline,
- endOfInput && leftover.position() == 0);
- if (nextLine != null) return nextLine;
- ByteBuffer b;
- BUFFERS:
- while ((b = queue.peek()) != null) {
- if (!b.hasRemaining()) {
- queue.poll();
- continue BUFFERS;
- }
- BYTES:
- while (b.hasRemaining()) {
- buffer.position(0);
- buffer.limit(buffer.capacity());
- boolean endofInput = completed && queue.size() <= 1;
- if (isUnderFlow(b, buffer, endofInput)) {
- assert !b.hasRemaining();
- if (buffer.position() > 0) {
- buffer.flip();
- builder.append(buffer);
- }
- continue BUFFERS;
- }
- CoderResult res = decoder.decode(b, buffer, endofInput);
- if (res.isError()) res.throwException();
- if (buffer.position() > 0) {
- buffer.flip();
- builder.append(buffer);
- continue LINES;
- }
- if (res.isUnderflow() && b.hasRemaining()) {
- //System.out.println("underflow: adding " + b.remaining() + " bytes");
- leftover.put(b);
- assert !b.hasRemaining();
- continue BUFFERS;
- }
- }
- }
-
- assert queue.isEmpty();
- if (endOfInput) {
- // Time to cleanup: there may be some undecoded leftover bytes
- // We need to flush them out.
- // The decoder has been configured to replace malformed/unmappable
- // chars with some replacement, in order to behave like
- // InputStreamReader.
- leftover.flip();
- buffer.position(0);
- buffer.limit(buffer.capacity());
-
- // decode() must be called just before flush, even if there
- // is nothing to decode. We must do this even if leftover
- // has no remaining bytes.
- CoderResult res = decoder.decode(leftover, buffer, endOfInput);
- if (buffer.position() > 0) {
- buffer.flip();
- builder.append(buffer);
- }
- if (res.isError()) res.throwException();
-
- // Now call decoder.flush()
- buffer.position(0);
- buffer.limit(buffer.capacity());
- res = decoder.flush(buffer);
- if (buffer.position() > 0) {
- buffer.flip();
- builder.append(buffer);
- }
- if (res.isError()) res.throwException();
-
- // It's possible that we reach here twice - just for the
- // purpose of checking that no bytes were left over, so
- // we reset leftover/decoder to make the function reentrant.
- leftover.position(0);
- leftover.limit(leftover.capacity());
- decoder.reset();
-
- // if some chars were produced then this call will
- // return them.
- return nextLine = nextLine(builder, newline, endOfInput);
- }
- return null;
- }
- return null;
- }
-
- // The main sequential scheduler loop.
- private void loop() {
- try {
- while (!cancelled) {
- Throwable error = errorRef.get();
- if (error != null) {
- cancelled = true;
- scheduler.stop();
- upstream.onError(error);
- cf.completeExceptionally(error);
- return;
- }
- if (nextLine == null) nextLine = nextLine();
- if (nextLine == null) {
- if (completed) {
- scheduler.stop();
- if (leftover.position() != 0) {
- // Underflow: not all bytes could be
- // decoded, but no more bytes will be coming.
- // This should not happen as we should already
- // have got a MalformedInputException, or
- // replaced the unmappable chars.
- errorRef.compareAndSet(null,
- new IllegalStateException(
- "premature end of input ("
- + leftover.position()
- + " undecoded bytes)"));
- continue;
- } else {
- upstream.onComplete();
- }
- return;
- } else if (demanded.get() == 0
- && !downstreamDemand.isFulfilled()) {
- long incr = Math.max(1, downstreamDemand.get());
- demanded.addAndGet(incr);
- upstreamSubscription.request(incr);
- continue;
- } else return;
- }
- assert nextLine != null;
- assert newline != null && !nextLine.endsWith(newline)
- || !nextLine.endsWith("\n") || !nextLine.endsWith("\r");
- if (downstreamDemand.tryDecrement()) {
- String forward = nextLine;
- nextLine = null;
- upstream.onNext(forward);
- } else return; // no demand: come back later
- }
- } catch (Throwable t) {
- try {
- upstreamSubscription.cancel();
- } finally {
- signalError(t);
- }
- }
- }
-
- static LineSubscription create(Flow.Subscription s,
- Charset charset,
- String lineSeparator,
- Flow.Subscriber<? super String> upstream,
- CompletableFuture<?> cf) {
- return new LineSubscription(Objects.requireNonNull(s),
- Objects.requireNonNull(charset).newDecoder()
- // use the same decoder configuration than
- // java.io.InputStreamReader
- .onMalformedInput(CodingErrorAction.REPLACE)
- .onUnmappableCharacter(CodingErrorAction.REPLACE),
- lineSeparator,
- Objects.requireNonNull(upstream),
- Objects.requireNonNull(cf));
- }
- }
-}
-