--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.net.http/share/classes/java/net/http/HttpResponse.java Wed Feb 07 14:17:24 2018 +0000
@@ -0,0 +1,1168 @@
+/*
+ * Copyright (c) 2015, 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 java.net.http;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.nio.ByteBuffer;
+import java.nio.charset.Charset;
+import java.nio.channels.FileChannel;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.OpenOption;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.Flow;
+import java.util.concurrent.Flow.Subscriber;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import java.util.stream.Stream;
+import javax.net.ssl.SSLParameters;
+import java.net.http.internal.BufferingSubscriber;
+import java.net.http.internal.LineSubscriberAdapter;
+import java.net.http.internal.ResponseBodyHandlers.FileDownloadBodyHandler;
+import java.net.http.internal.ResponseBodyHandlers.PathBodyHandler;
+import java.net.http.internal.ResponseBodyHandlers.PushPromisesHandlerWithMap;
+import java.net.http.internal.ResponseSubscribers;
+import static java.net.http.internal.common.Utils.charsetFrom;
+
+/**
+ * Represents a response to a {@link HttpRequest}.
+ *
+ * <p> A {@code HttpResponse} is available when the response status code and
+ * headers have been received, and typically after the response body has also
+ * been received. This depends on the response body handler provided when
+ * sending the request. In all cases, the response body handler is invoked
+ * before the body is read. This gives applications an opportunity to decide
+ * how to handle the body.
+ *
+ * <p> Methods are provided in this class for accessing the response headers,
+ * and response body.
+ *
+ * <p><b>Response handlers and subscribers</b>
+ *
+ * <p> Response bodies are handled at two levels. Application code supplies a
+ * response handler ({@link BodyHandler}) which may examine the response status
+ * code and headers, and which then returns a {@link BodySubscriber} to actually
+ * read (or discard) the body and convert it into some useful Java object type.
+ * The handler can return one of the pre-defined subscriber types, or a custom
+ * subscriber, or if the body is to be discarded it can call {@link
+ * BodySubscriber#discard() discard} and return a subscriber which
+ * discards the response body. Static implementations of both handlers and
+ * subscribers are provided in {@linkplain BodyHandler BodyHandler} and
+ * {@linkplain BodySubscriber BodySubscriber} respectively. In all cases, the
+ * handler functions provided are convenience implementations which ignore the
+ * supplied status code and headers and return the relevant pre-defined {@code
+ * BodySubscriber}.
+ *
+ * <p> See {@link BodyHandler} for example usage.
+ *
+ * @param <T> the response body type
+ * @since 11
+ */
+public abstract class HttpResponse<T> {
+
+ /**
+ * Creates an HttpResponse.
+ */
+ protected HttpResponse() { }
+
+ /**
+ * Returns the status code for this response.
+ *
+ * @return the response code
+ */
+ public abstract int statusCode();
+
+ /**
+ * Returns the {@link HttpRequest} corresponding to this response.
+ *
+ * <p> This may not be the original request provided by the caller,
+ * for example, if that request was redirected.
+ *
+ * @see #previousResponse()
+ *
+ * @return the request
+ */
+ public abstract HttpRequest request();
+
+ /**
+ * Returns an {@code Optional} containing the previous intermediate response
+ * if one was received. An intermediate response is one that is received
+ * as a result of redirection or authentication. If no previous response
+ * was received then an empty {@code Optional} is returned.
+ *
+ * @return an Optional containing the HttpResponse, if any.
+ */
+ public abstract Optional<HttpResponse<T>> previousResponse();
+
+ /**
+ * Returns the received response headers.
+ *
+ * @return the response headers
+ */
+ public abstract HttpHeaders headers();
+
+ /**
+ * Returns the body. Depending on the type of {@code T}, the returned body
+ * may represent the body after it was read (such as {@code byte[]}, or
+ * {@code String}, or {@code Path}) or it may represent an object with
+ * which the body is read, such as an {@link java.io.InputStream}.
+ *
+ * <p> If this {@code HttpResponse} was returned from an invocation of
+ * {@link #previousResponse()} then this method returns {@code null}
+ *
+ * @return the body
+ */
+ public abstract T body();
+
+ /**
+ * Returns the {@link javax.net.ssl.SSLParameters} in effect for this
+ * response. Returns {@code null} if this is not a HTTPS response.
+ *
+ * @return the SSLParameters associated with the response
+ */
+ public abstract SSLParameters sslParameters();
+
+ /**
+ * Returns the {@code URI} that the response was received from. This may be
+ * different from the request {@code URI} if redirection occurred.
+ *
+ * @return the URI of the response
+ */
+ public abstract URI uri();
+
+ /**
+ * Returns the HTTP protocol version that was used for this response.
+ *
+ * @return HTTP protocol version
+ */
+ public abstract HttpClient.Version version();
+
+
+ private static String pathForSecurityCheck(Path path) {
+ return path.toFile().getPath();
+ }
+
+
+ /**
+ * A handler for response bodies.
+ *
+ * <p> This is a function that takes two parameters: the response status code,
+ * and the response headers, and which returns a {@linkplain BodySubscriber}.
+ * The function is always called just before the response body is read. Its
+ * implementation may examine the status code or headers and must decide,
+ * whether to accept the response body or discard it, and if accepting it,
+ * exactly how to handle it.
+ *
+ * <p> Some pre-defined implementations which do not utilize the status code
+ * or headers (meaning the body is always accepted) are defined:
+ * <ul><li>{@link #asByteArray() }</li>
+ * <li>{@link #asByteArrayConsumer(java.util.function.Consumer)
+ * asByteArrayConsumer(Consumer)}</li>
+ * <li>{@link #asString(java.nio.charset.Charset) asString(Charset)}</li>
+ * <li>{@link #asFile(Path, OpenOption...)
+ * asFile(Path,OpenOption...)}</li>
+ * <li>{@link #asFileDownload(java.nio.file.Path,OpenOption...)
+ * asFileDownload(Path,OpenOption...)}</li>
+ * <li>{@link #asInputStream() asInputStream()}</li>
+ * <li>{@link #discard() }</li>
+ * <li>{@link #replace(Object) }</li>
+ * <li>{@link #buffering(BodyHandler, int)
+ * buffering(BodyHandler,int)}</li>
+ * </ul>
+ *
+ * <p> These implementations return the equivalent {@link BodySubscriber}.
+ * Alternatively, the handler can be used to examine the status code
+ * or headers and return different body subscribers as appropriate.
+ *
+ * <p><b>Examples of handler usage</b>
+ *
+ * <p> The first example uses one of the predefined handler functions which
+ * ignores the response headers and status, and always process the response
+ * body in the same way.
+ * <pre>
+ * {@code
+ * HttpResponse<Path> resp = HttpRequest
+ * .create(URI.create("http://www.foo.com"))
+ * .GET()
+ * .response(BodyHandler.asFile(Paths.get("/tmp/f")));
+ * }
+ * </pre>
+ * Note, that even though these pre-defined handlers ignore the status code
+ * and headers, this information is still accessible from the
+ * {@code HttpResponse} when it is returned.
+ *
+ * <p> In the second example, the function returns a different subscriber
+ * depending on the status code.
+ * <pre>
+ * {@code
+ * HttpResponse<Path> resp1 = HttpRequest
+ * .create(URI.create("http://www.foo.com"))
+ * .GET()
+ * .response(
+ * (status, headers) -> status == 200
+ * ? BodySubscriber.asFile(Paths.get("/tmp/f"))
+ * : BodySubscriber.replace(Paths.get("/NULL")));
+ * }
+ * </pre>
+ *
+ * @param <T> the response body type
+ */
+ @FunctionalInterface
+ public interface BodyHandler<T> {
+ /**
+ * Returns a {@link BodySubscriber BodySubscriber} considering the given
+ * response status code and headers. This method is always called before
+ * the body is read and its implementation can decide to keep the body
+ * and store it somewhere, or else discard it by returning the {@code
+ * BodySubscriber} returned from {@link BodySubscriber#discard()
+ * discard}.
+ *
+ * @param statusCode the HTTP status code received
+ * @param responseHeaders the response headers received
+ * @return a body subscriber
+ */
+ public BodySubscriber<T> apply(int statusCode, HttpHeaders responseHeaders);
+
+
+ /**
+ * Returns a response body handler that returns a {@link BodySubscriber
+ * BodySubscriber}{@code <Void>} obtained from {@linkplain
+ * BodySubscriber#fromSubscriber(Subscriber)}, with the given
+ * {@code subscriber}.
+ *
+ * <p> The response body is not available through this, or the {@code
+ * HttpResponse} API, but instead all response body is forwarded to the
+ * given {@code subscriber}, which should make it available, if
+ * appropriate, through some other mechanism, e.g. an entry in a
+ * database, etc.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * <p> For example:
+ * <pre> {@code
+ * TextSubscriber subscriber = new TextSubscriber();
+ * HttpResponse<Void> response = client.sendAsync(request,
+ * BodyHandler.fromSubscriber(subscriber)).join();
+ * System.out.println(response.statusCode());
+ * }</pre>
+ *
+ * @param subscriber the subscriber
+ * @return a response body handler
+ */
+ public static BodyHandler<Void>
+ fromSubscriber(Subscriber<? super List<ByteBuffer>> subscriber) {
+ Objects.requireNonNull(subscriber);
+ return (status, headers) -> BodySubscriber.fromSubscriber(subscriber,
+ s -> null);
+ }
+
+ /**
+ * Returns a response body handler that returns a {@link BodySubscriber
+ * BodySubscriber}{@code <T>} obtained from {@link
+ * BodySubscriber#fromSubscriber(Subscriber, Function)}, with the
+ * given {@code subscriber} and {@code finisher} function.
+ *
+ * <p> The given {@code finisher} function is applied after the given
+ * subscriber's {@code onComplete} has been invoked. The {@code finisher}
+ * function is invoked with the given subscriber, and returns a value
+ * that is set as the response's body.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * <p> For example:
+ * <pre> {@code
+ * TextSubscriber subscriber = ...; // accumulates bytes and transforms them into a String
+ * HttpResponse<String> response = client.sendAsync(request,
+ * BodyHandler.fromSubscriber(subscriber, TextSubscriber::getTextResult)).join();
+ * String text = response.body();
+ * }</pre>
+ *
+ * @param <S> the type of the Subscriber
+ * @param <T> the type of the response body
+ * @param subscriber the subscriber
+ * @param finisher a function to be applied after the subscriber has completed
+ * @return a response body handler
+ */
+ public static <S extends Subscriber<? super List<ByteBuffer>>,T> BodyHandler<T>
+ fromSubscriber(S subscriber, Function<S,T> finisher) {
+ Objects.requireNonNull(subscriber);
+ Objects.requireNonNull(finisher);
+ return (status, headers) -> BodySubscriber.fromSubscriber(subscriber,
+ finisher);
+ }
+
+ /**
+ * Returns a response body handler that returns a {@link BodySubscriber
+ * BodySubscriber}{@code <Void>} obtained from {@link
+ * BodySubscriber#fromLineSubscriber(Subscriber, Function, Charset, String)
+ * BodySubscriber.fromLineSubscriber(subscriber, s -> null, charset, null)},
+ * with the given {@code subscriber}.
+ * The {@link Charset charset} used to decode the response body bytes is
+ * obtained from the HTTP response headers as specified by {@link #asString()},
+ * and lines are delimited in the manner of {@link BufferedReader#readLine()}.
+ *
+ * <p> The response body is not available through this, or the {@code
+ * HttpResponse} API, but instead all response body is forwarded to the
+ * given {@code subscriber}, which should make it available, if
+ * appropriate, through some other mechanism, e.g. an entry in a
+ * database, etc.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * <p> For example:
+ * <pre> {@code
+ * TextSubscriber subscriber = new TextSubscriber();
+ * HttpResponse<Void> response = client.sendAsync(request,
+ * BodyHandler.fromLineSubscriber(subscriber, "\n")).join();
+ * System.out.println(response.statusCode());
+ * }</pre>
+ *
+ * @param subscriber the subscriber
+ * @return a response body handler
+ */
+ public static BodyHandler<Void>
+ fromLineSubscriber(Subscriber<? super String> subscriber) {
+ Objects.requireNonNull(subscriber);
+ return (status, headers)
+ -> BodySubscriber.fromLineSubscriber(subscriber, s -> null,
+ charsetFrom(headers), null);
+ }
+
+ /**
+ * Returns a response body handler that returns a {@link BodySubscriber
+ * BodySubscriber}{@code <T>} obtained from {@link
+ * BodySubscriber#fromLineSubscriber(Subscriber, Function, Charset, String)
+ * BodySubscriber.fromLineSubscriber(subscriber, finisher, charset, lineSeparator)},
+ * with the given {@code subscriber}, {@code finisher} function, and line separator.
+ * The {@link Charset charset} used to decode the response body bytes is
+ * obtained from the HTTP response headers as specified by {@link #asString()}.
+ *
+ * <p> The given {@code finisher} function is applied after the given
+ * subscriber's {@code onComplete} has been invoked. The {@code finisher}
+ * function is invoked with the given subscriber, and returns a value
+ * that is set as the response's body.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * <p> For example:
+ * <pre> {@code
+ * TextSubscriber subscriber = ...; // accumulates bytes and transforms them into a String
+ * HttpResponse<String> response = client.sendAsync(request,
+ * BodyHandler.fromSubscriber(subscriber, TextSubscriber::getTextResult, "\n")).join();
+ * String text = response.body();
+ * }</pre>
+ *
+ * @param <S> the type of the Subscriber
+ * @param <T> the type of the response body
+ * @param subscriber the subscriber
+ * @param finisher a function to be applied after the subscriber has completed
+ * @param lineSeparator an optional line separator: can be {@code null},
+ * in which case lines will be delimited in the manner of
+ * {@link BufferedReader#readLine()}.
+ * @return a response body handler
+ * @throws IllegalArgumentException if the supplied {@code lineSeparator} is the empty string.
+ */
+ public static <S extends Subscriber<? super String>,T> BodyHandler<T>
+ fromLineSubscriber(S subscriber, Function<S,T> finisher, String lineSeparator) {
+ Objects.requireNonNull(subscriber);
+ Objects.requireNonNull(finisher);
+ // implicit null check
+ if (lineSeparator != null && lineSeparator.isEmpty())
+ throw new IllegalArgumentException("empty line separator");
+ return (status, headers) ->
+ BodySubscriber.fromLineSubscriber(subscriber, finisher,
+ charsetFrom(headers), lineSeparator);
+ }
+
+ /**
+ * Returns a response body handler which discards the response body.
+ *
+ * @return a response body handler
+ */
+ public static BodyHandler<Void> discard() {
+ return (status, headers) -> BodySubscriber.discard();
+ }
+
+ /**
+ * Returns a response body handler which discards the response body and
+ * uses the given value as a replacement for it.
+ *
+ * @param <U> the response body type
+ * @param value the value of U to return as the body, may be {@code null}
+ * @return a response body handler
+ */
+ public static <U> BodyHandler<U> replace(U value) {
+ return (status, headers) -> BodySubscriber.replace(value);
+ }
+
+ /**
+ * Returns a {@code BodyHandler<String>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <String>} obtained from
+ * {@link BodySubscriber#asString(Charset) BodySubscriber.asString(Charset)}.
+ * The body is decoded using the given character set.
+ *
+ * @param charset the character set to convert the body with
+ * @return a response body handler
+ */
+ public static BodyHandler<String> asString(Charset charset) {
+ Objects.requireNonNull(charset);
+ return (status, headers) -> BodySubscriber.asString(charset);
+ }
+
+ /**
+ * Returns a {@code BodyHandler<Path>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <Path>} obtained from
+ * {@link BodySubscriber#asFile(Path, OpenOption...)
+ * BodySubscriber.asFile(Path,OpenOption...)}.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body has
+ * been completely written to the file, and {@link #body()} returns a
+ * reference to its {@link Path}.
+ *
+ * @param file the filename to store the body in
+ * @param openOptions any options to use when opening/creating the file
+ * @return a response body handler
+ * @throws SecurityException If a security manager has been installed
+ * and it denies {@link SecurityManager#checkWrite(String)
+ * write access} to the file. The {@link
+ * SecurityManager#checkDelete(String) checkDelete} method is
+ * invoked to check delete access if the file is opened with
+ * the {@code DELETE_ON_CLOSE} option.
+ */
+ public static BodyHandler<Path> asFile(Path file, OpenOption... openOptions) {
+ Objects.requireNonNull(file);
+ List<OpenOption> opts = List.of(openOptions);
+ SecurityManager sm = System.getSecurityManager();
+ if (sm != null) {
+ String fn = pathForSecurityCheck(file);
+ sm.checkWrite(fn);
+ if (opts.contains(StandardOpenOption.DELETE_ON_CLOSE))
+ sm.checkDelete(fn);
+ if (opts.contains(StandardOpenOption.READ))
+ sm.checkRead(fn);
+ }
+ return new PathBodyHandler(file, openOptions);
+ }
+
+ /**
+ * Returns a {@code BodyHandler<Path>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <Path>} obtained from
+ * {@link BodySubscriber#asFile(Path) BodySubscriber.asFile(Path)}.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body has
+ * been completely written to the file, and {@link #body()} returns a
+ * reference to its {@link Path}.
+ *
+ * @param file the file to store the body in
+ * @return a response body handler
+ * @throws SecurityException if a security manager has been installed
+ * and it denies {@link SecurityManager#checkWrite(String)
+ * write access} to the file
+ */
+ public static BodyHandler<Path> asFile(Path file) {
+ return BodyHandler.asFile(file, StandardOpenOption.CREATE,
+ StandardOpenOption.WRITE);
+ }
+
+ /**
+ * Returns a {@code BodyHandler<Path>} that returns a
+ * {@link BodySubscriber BodySubscriber}<{@link Path}>
+ * where the download directory is specified, but the filename is
+ * obtained from the {@code Content-Disposition} response header. The
+ * {@code Content-Disposition} header must specify the <i>attachment</i>
+ * type and must also contain a <i>filename</i> parameter. If the
+ * filename specifies multiple path components only the final component
+ * is used as the filename (with the given directory name).
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body has
+ * been completely written to the file and {@link #body()} returns a
+ * {@code Path} object for the file. The returned {@code Path} is the
+ * combination of the supplied directory name and the file name supplied
+ * by the server. If the destination directory does not exist or cannot
+ * be written to, then the response will fail with an {@link IOException}.
+ *
+ * @param directory the directory to store the file in
+ * @param openOptions open options
+ * @return a response body handler
+ * @throws SecurityException If a security manager has been installed
+ * and it denies {@link SecurityManager#checkWrite(String)
+ * write access} to the file. The {@link
+ * SecurityManager#checkDelete(String) checkDelete} method is
+ * invoked to check delete access if the file is opened with
+ * the {@code DELETE_ON_CLOSE} option.
+ */
+ //####: check if the dir exists and is writable??
+ public static BodyHandler<Path> asFileDownload(Path directory,
+ OpenOption... openOptions) {
+ Objects.requireNonNull(directory);
+ List<OpenOption> opts = List.of(openOptions);
+ SecurityManager sm = System.getSecurityManager();
+ if (sm != null) {
+ String fn = pathForSecurityCheck(directory);
+ sm.checkWrite(fn);
+ if (opts.contains(StandardOpenOption.DELETE_ON_CLOSE))
+ sm.checkDelete(fn);
+ if (opts.contains(StandardOpenOption.READ))
+ sm.checkRead(fn);
+ }
+ return new FileDownloadBodyHandler(directory, openOptions);
+ }
+
+ /**
+ * Returns a {@code BodyHandler<InputStream>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <InputStream>} obtained
+ * from {@link BodySubscriber#asInputStream() BodySubscriber.asInputStream}.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the response
+ * headers will have been completely read, but the body may not have
+ * been fully received yet. The {@link #body()} method returns an
+ * {@link InputStream} from which the body can be read as it is received.
+ *
+ * @apiNote See {@link BodySubscriber#asInputStream()} for more information.
+ *
+ * @return a response body handler
+ */
+ public static BodyHandler<InputStream> asInputStream() {
+ return (status, headers) -> BodySubscriber.asInputStream();
+ }
+
+ /**
+ * Returns a {@code BodyHandler<Stream<String>>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <Stream<String>>} obtained from
+ * {@link BodySubscriber#asLines(Charset)
+ * BodySubscriber.asLines(charset)}.
+ * The {@link Charset charset} used to decode the response body bytes is
+ * obtained from the HTTP response headers as specified by {@link #asString()},
+ * and lines are delimited in the manner of {@link BufferedReader#readLine()}.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body may
+ * not have been completely received.
+ *
+ * @return a response body handler
+ */
+ public static BodyHandler<Stream<String>> asLines() {
+ return (status, headers) ->
+ BodySubscriber.asLines(charsetFrom(headers));
+ }
+
+ /**
+ * Returns a {@code BodyHandler<Void>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <Void>} obtained from
+ * {@link BodySubscriber#asByteArrayConsumer(Consumer)
+ * BodySubscriber.asByteArrayConsumer(Consumer)}.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body has
+ * been completely written to the consumer.
+ * @apiNote
+ * The subscriber returned by this handler is not flow controlled.
+ * Therefore, the supplied consumer must be able to process whatever
+ * amount of data is delivered in a timely fashion.
+ *
+ * @param consumer a Consumer to accept the response body
+ * @return a response body handler
+ */
+ public static BodyHandler<Void> asByteArrayConsumer(Consumer<Optional<byte[]>> consumer) {
+ Objects.requireNonNull(consumer);
+ return (status, headers) -> BodySubscriber.asByteArrayConsumer(consumer);
+ }
+
+ /**
+ * Returns a {@code BodyHandler<byte[]>} that returns a
+ * {@link BodySubscriber BodySubscriber}<{@code byte[]}> obtained
+ * from {@link BodySubscriber#asByteArray() BodySubscriber.asByteArray()}.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body has
+ * been completely written to the byte array.
+ *
+ * @return a response body handler
+ */
+ public static BodyHandler<byte[]> asByteArray() {
+ return (status, headers) -> BodySubscriber.asByteArray();
+ }
+
+ /**
+ * Returns a {@code BodyHandler<String>} that returns a
+ * {@link BodySubscriber BodySubscriber}{@code <String>} obtained from
+ * {@link BodySubscriber#asString(java.nio.charset.Charset)
+ * BodySubscriber.asString(Charset)}. The body is
+ * decoded using the character set specified in
+ * the {@code Content-type} response header. If there is no such
+ * header, or the character set is not supported, then
+ * {@link java.nio.charset.StandardCharsets#UTF_8 UTF_8} is used.
+ *
+ * <p> When the {@code HttpResponse} object is returned, the body has
+ * been completely written to the string.
+ *
+ * @return a response body handler
+ */
+ public static BodyHandler<String> asString() {
+ return (status, headers) -> BodySubscriber.asString(charsetFrom(headers));
+ }
+
+ /**
+ * Returns a {@code BodyHandler} which, when invoked, returns a {@linkplain
+ * BodySubscriber#buffering(BodySubscriber,int) buffering BodySubscriber}
+ * that buffers data before delivering it to the downstream subscriber.
+ * These {@code BodySubscriber} instances are created by calling
+ * {@linkplain BodySubscriber#buffering(BodySubscriber,int)
+ * BodySubscriber.buffering} with a subscriber obtained from the given
+ * downstream handler and the {@code bufferSize} parameter.
+ *
+ * @param downstreamHandler the downstream handler
+ * @param bufferSize the buffer size parameter passed to {@linkplain
+ * BodySubscriber#buffering(BodySubscriber,int) BodySubscriber.buffering}
+ * @return a body handler
+ * @throws IllegalArgumentException if {@code bufferSize <= 0}
+ */
+ public static <T> BodyHandler<T> buffering(BodyHandler<T> downstreamHandler,
+ int bufferSize) {
+ Objects.requireNonNull(downstreamHandler);
+ if (bufferSize <= 0)
+ throw new IllegalArgumentException("must be greater than 0");
+ return (status, headers) -> BodySubscriber
+ .buffering(downstreamHandler.apply(status, headers),
+ bufferSize);
+ }
+ }
+
+ /**
+ * A handler for push promises.
+ *
+ * <p> A <i>push promise</i> is a synthetic request sent by an HTTP/2 server
+ * when retrieving an initiating client-sent request. The server has
+ * determined, possibly through inspection of the initiating request, that
+ * the client will likely need the promised resource, and hence pushes a
+ * synthetic push request, in the form of a push promise, to the client. The
+ * client can choose to accept or reject the push promise request.
+ *
+ * <p> A push promise request may be received up to the point where the
+ * response body of the initiating client-sent request has been fully
+ * received. The delivery of a push promise response, however, is not
+ * coordinated with the delivery of the response to the initiating
+ * client-sent request.
+ *
+ * @param <T> the push promise response body type
+ */
+ public interface PushPromiseHandler<T> {
+ /**
+ * Notification of an incoming push promise.
+ *
+ * <p> This method is invoked once for each push promise received, up
+ * to the point where the response body of the initiating client-sent
+ * request has been fully received.
+ *
+ * <p> A push promise is accepted by invoking the given {@code acceptor}
+ * function. The {@code acceptor} function must be passed a non-null
+ * {@code BodyHandler}, that is to be used to handle the promise's
+ * response body. The acceptor function will return a {@code
+ * CompletableFuture} that completes with the promise's response.
+ *
+ * <p> If the {@code acceptor} function is not successfully invoked,
+ * then the push promise is rejected. The {@code acceptor} function will
+ * throw an {@code IllegalStateException} if invoked more than once.
+ *
+ * @param initiatingRequest the initiating client-send request
+ * @param pushPromiseRequest the synthetic push request
+ * @param acceptor the acceptor function that must be successfully
+ * invoked to accept the push promise
+ */
+ public void applyPushPromise(
+ HttpRequest initiatingRequest,
+ HttpRequest pushPromiseRequest,
+ Function<HttpResponse.BodyHandler<T>,CompletableFuture<HttpResponse<T>>> acceptor
+ );
+
+
+ /**
+ * Returns a push promise handler that accumulates push promises, and
+ * their responses, into the given map.
+ *
+ * <p> Entries are added to the given map for each push promise accepted.
+ * The entry's key is the push request, and the entry's value is a
+ * {@code CompletableFuture} that completes with the response
+ * corresponding to the key's push request. A push request is rejected /
+ * cancelled if there is already an entry in the map whose key is
+ * {@linkplain HttpRequest#equals equal} to it. A push request is
+ * rejected / cancelled if it does not have the same origin as its
+ * initiating request.
+ *
+ * <p> Entries are added to the given map as soon as practically
+ * possible when a push promise is received and accepted. That way code,
+ * using such a map like a cache, can determine if a push promise has
+ * been issued by the server and avoid making, possibly, unnecessary
+ * requests.
+ *
+ * <p> The delivery of a push promise response is not coordinated with
+ * the delivery of the response to the initiating client-sent request.
+ * However, when the response body for the initiating client-sent
+ * request has been fully received, the map is guaranteed to be fully
+ * populated, that is, no more entries will be added. The individual
+ * {@code CompletableFutures} contained in the map may or may not
+ * already be completed at this point.
+ *
+ * @param <T> the push promise response body type
+ * @param pushPromiseHandler t he body handler to use for push promises
+ * @param pushPromisesMap a map to accumulate push promises into
+ * @return a push promise handler
+ */
+ public static <T> PushPromiseHandler<T>
+ of(Function<HttpRequest,BodyHandler<T>> pushPromiseHandler,
+ ConcurrentMap<HttpRequest,CompletableFuture<HttpResponse<T>>> pushPromisesMap) {
+ return new PushPromisesHandlerWithMap<>(pushPromiseHandler, pushPromisesMap);
+ }
+ }
+
+ /**
+ * A subscriber for response bodies.
+ *
+ * <p> The object acts as a {@link Flow.Subscriber}<{@link List}<{@link
+ * ByteBuffer}>> to the HTTP client implementation, which publishes
+ * unmodifiable lists of read-only ByteBuffers containing the response body.
+ * The Flow of data, as well as the order of ByteBuffers in the Flow lists,
+ * is a strictly ordered representation of the response body. Both the Lists
+ * and the ByteBuffers, once passed to the subscriber, are no longer used by
+ * the HTTP client. The subscriber converts the incoming buffers of data to
+ * some user-defined object type {@code T}.
+ *
+ * <p> The {@link #getBody()} method returns a {@link CompletionStage}{@code
+ * <T>} that provides the response body object. The {@code CompletionStage}
+ * must be obtainable at any time. When it completes depends on the nature
+ * of type {@code T}. In many cases, when {@code T} represents the entire
+ * body after being read then it completes after the body has been read. If
+ * {@code T} is a streaming type such as {@link java.io.InputStream} then it
+ * completes before the body has been read, because the calling code uses it
+ * to consume the data.
+ *
+ * @apiNote To ensure that all resources associated with the
+ * corresponding exchange are properly released, an implementation
+ * of {@code BodySubscriber} must ensure to {@linkplain
+ * Flow.Subscription#request request} more data until {@link
+ * #onComplete() onComplete} or {@link #onError(Throwable) onError}
+ * are signalled, or {@linkplain Flow.Subscription#request cancel} its
+ * {@linkplain #onSubscribe(Flow.Subscription) subscription}
+ * if unable or unwilling to do so.
+ * Calling {@code cancel} before exhausting the data may cause
+ * the underlying HTTP connection to be closed and prevent it
+ * from being reused for subsequent operations.
+ *
+ * @param <T> the response body type
+ */
+ public interface BodySubscriber<T>
+ extends Flow.Subscriber<List<ByteBuffer>> {
+
+ /**
+ * Returns a {@code CompletionStage} which when completed will return
+ * the response body object. This method can be called at any time
+ * relative to the other {@link Flow.Subscriber} methods and is invoked
+ * using the client's {@link Executor}.
+ *
+ * @return a CompletionStage for the response body
+ */
+ public CompletionStage<T> getBody();
+
+ /**
+ * Returns a body subscriber that forwards all response body to the
+ * given {@code Flow.Subscriber}. The {@linkplain #getBody() completion
+ * stage} of the returned body subscriber completes after one of the
+ * given subscribers {@code onComplete} or {@code onError} has been
+ * invoked.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * @param <S> the type of the Subscriber
+ * @param subscriber the subscriber
+ * @return a body subscriber
+ */
+ public static <S extends Subscriber<? super List<ByteBuffer>>> BodySubscriber<Void>
+ fromSubscriber(S subscriber) {
+ return new ResponseSubscribers.SubscriberAdapter<S,Void>(subscriber, s -> null);
+ }
+
+ /**
+ * Returns a body subscriber that forwards all response body to the
+ * given {@code Flow.Subscriber}. The {@linkplain #getBody() completion
+ * stage} of the returned body subscriber completes after one of the
+ * given subscribers {@code onComplete} or {@code onError} has been
+ * invoked.
+ *
+ * <p> The given {@code finisher} function is applied after the given
+ * subscriber's {@code onComplete} has been invoked. The {@code finisher}
+ * function is invoked with the given subscriber, and returns a value
+ * that is set as the response's body.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * @param <S> the type of the Subscriber
+ * @param <T> the type of the response body
+ * @param subscriber the subscriber
+ * @param finisher a function to be applied after the subscriber has
+ * completed
+ * @return a body subscriber
+ */
+ public static <S extends Subscriber<? super List<ByteBuffer>>,T> BodySubscriber<T>
+ fromSubscriber(S subscriber,
+ Function<S,T> finisher) {
+ return new ResponseSubscribers.SubscriberAdapter<S,T>(subscriber, finisher);
+ }
+
+ /**
+ * Returns a body subscriber that forwards all response body to the
+ * given {@code Flow.Subscriber}, lines by lines.
+ * The {@linkplain #getBody() completion
+ * stage} of the returned body subscriber completes after one of the
+ * given subscribers {@code onComplete} or {@code onError} has been
+ * invoked.
+ * Bytes are decoded using the {@linkplain StandardCharsets#UTF_8
+ * UTF-8} charset, and lines are delimited in the manner of
+ * {@link BufferedReader#readLine()}.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * @implNote This is equivalent to calling <pre>{@code
+ * fromLineSubscriber(subscriber, s -> null, StandardCharsets.UTF_8, null)
+ * }</pre>
+ *
+ * @param <S> the type of the Subscriber
+ * @param subscriber the subscriber
+ * @return a body subscriber
+ */
+ public static <S extends Subscriber<? super String>> BodySubscriber<Void>
+ fromLineSubscriber(S subscriber) {
+ return fromLineSubscriber(subscriber, s -> null,
+ StandardCharsets.UTF_8, null);
+ }
+
+ /**
+ * Returns a body subscriber that forwards all response body to the
+ * given {@code Flow.Subscriber}, lines by lines.
+ * The {@linkplain #getBody() completion
+ * stage} of the returned body subscriber completes after one of the
+ * given subscribers {@code onComplete} or {@code onError} has been
+ * invoked.
+ *
+ * <p> The given {@code finisher} function is applied after the given
+ * subscriber's {@code onComplete} has been invoked. The {@code finisher}
+ * function is invoked with the given subscriber, and returns a value
+ * that is set as the response's body.
+ *
+ * @apiNote This method can be used as an adapter between {@code
+ * BodySubscriber} and {@code Flow.Subscriber}.
+ *
+ * @param <S> the type of the Subscriber
+ * @param <T> the type of the response body
+ * @param subscriber the subscriber
+ * @param finisher a function to be applied after the subscriber has
+ * completed
+ * @param charset a {@link Charset} to decode the bytes
+ * @param lineSeparator an optional line separator: can be {@code null},
+ * in which case lines will be delimited in the manner of
+ * {@link BufferedReader#readLine()}.
+ * @return a body subscriber
+ * @throws IllegalArgumentException if the supplied {@code lineSeparator} is the empty string.
+ */
+ public static <S extends Subscriber<? super String>,T> BodySubscriber<T>
+ fromLineSubscriber(S subscriber,
+ Function<S,T> finisher,
+ Charset charset,
+ String lineSeparator) {
+ return LineSubscriberAdapter.create(subscriber,
+ finisher, charset, lineSeparator);
+ }
+
+ /**
+ * Returns a body subscriber which stores the response body as a {@code
+ * String} converted using the given {@code Charset}.
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available after
+ * the entire response has been read.
+ *
+ * @param charset the character set to convert the String with
+ * @return a body subscriber
+ */
+ public static BodySubscriber<String> asString(Charset charset) {
+ Objects.requireNonNull(charset);
+ return new ResponseSubscribers.ByteArraySubscriber<>(
+ bytes -> new String(bytes, charset)
+ );
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which stores the response body as a
+ * byte array.
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available after
+ * the entire response has been read.
+ *
+ * @return a body subscriber
+ */
+ public static BodySubscriber<byte[]> asByteArray() {
+ return new ResponseSubscribers.ByteArraySubscriber<>(
+ Function.identity() // no conversion
+ );
+ }
+
+ // no security check
+ private static BodySubscriber<Path> asFileImpl(Path file, OpenOption... openOptions) {
+ return new ResponseSubscribers.PathSubscriber(file, openOptions);
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which stores the response body in a
+ * file opened with the given options and name. The file will be opened
+ * with the given options using {@link FileChannel#open(Path,OpenOption...)
+ * FileChannel.open} just before the body is read. Any exception thrown
+ * will be returned or thrown from {@link HttpClient#send(HttpRequest,
+ * BodyHandler) HttpClient::send} or {@link HttpClient#sendAsync(HttpRequest,
+ * BodyHandler) HttpClient::sendAsync} as appropriate.
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available after
+ * the entire response has been read.
+ *
+ * @param file the file to store the body in
+ * @param openOptions the list of options to open the file with
+ * @return a body subscriber
+ * @throws SecurityException If a security manager has been installed
+ * and it denies {@link SecurityManager#checkWrite(String)
+ * write access} to the file. The {@link
+ * SecurityManager#checkDelete(String) checkDelete} method is
+ * invoked to check delete access if the file is opened with the
+ * {@code DELETE_ON_CLOSE} option.
+ */
+ public static BodySubscriber<Path> asFile(Path file, OpenOption... openOptions) {
+ Objects.requireNonNull(file);
+ List<OpenOption> opts = List.of(openOptions);
+ SecurityManager sm = System.getSecurityManager();
+ if (sm != null) {
+ String fn = pathForSecurityCheck(file);
+ sm.checkWrite(fn);
+ if (opts.contains(StandardOpenOption.DELETE_ON_CLOSE))
+ sm.checkDelete(fn);
+ if (opts.contains(StandardOpenOption.READ))
+ sm.checkRead(fn);
+ }
+ return asFileImpl(file, openOptions);
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which stores the response body in a
+ * file opened with the given name. Has the same effect as calling
+ * {@link #asFile(Path, OpenOption...) asFile} with the standard open
+ * options {@code CREATE} and {@code WRITE}
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available after
+ * the entire response has been read.
+ *
+ * @param file the file to store the body in
+ * @return a body subscriber
+ * @throws SecurityException if a security manager has been installed
+ * and it denies {@link SecurityManager#checkWrite(String)
+ * write access} to the file
+ */
+ public static BodySubscriber<Path> asFile(Path file) {
+ return asFile(file, StandardOpenOption.CREATE, StandardOpenOption.WRITE);
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which provides the incoming body
+ * data to the provided Consumer of {@code Optional<byte[]>}. Each
+ * call to {@link Consumer#accept(java.lang.Object) Consumer.accept()}
+ * will contain a non empty {@code Optional}, except for the final
+ * invocation after all body data has been read, when the {@code
+ * Optional} will be empty.
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available after
+ * the entire response has been read.
+ *
+ * @apiNote
+ * This subscriber is not flow controlled.
+ * Therefore, the supplied consumer must be able to process whatever
+ * amount of data is delivered in a timely fashion.
+ *
+ * @param consumer a Consumer of byte arrays
+ * @return a BodySubscriber
+ */
+ public static BodySubscriber<Void> asByteArrayConsumer(Consumer<Optional<byte[]>> consumer) {
+ return new ResponseSubscribers.ConsumerSubscriber(consumer);
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which streams the response body as
+ * an {@link InputStream}.
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available
+ * immediately after the response headers have been read, without
+ * requiring to wait for the entire body to be processed. The response
+ * body can then be read directly from the {@link InputStream}.
+ *
+ * @apiNote To ensure that all resources associated with the
+ * corresponding exchange are properly released the caller must
+ * ensure to either read all bytes until EOF is reached, or call
+ * {@link InputStream#close} if it is unable or unwilling to do so.
+ * Calling {@code close} before exhausting the stream may cause
+ * the underlying HTTP connection to be closed and prevent it
+ * from being reused for subsequent operations.
+ *
+ * @return a body subscriber that streams the response body as an
+ * {@link InputStream}.
+ */
+ public static BodySubscriber<InputStream> asInputStream() {
+ return new ResponseSubscribers.HttpResponseInputStream();
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which streams the response body as
+ * a {@link Stream Stream<String>}, where each string in the stream
+ * corresponds to a line as defined by {@link BufferedReader#lines()}.
+ *
+ * <p> The {@link HttpResponse} using this subscriber is available
+ * immediately after the response headers have been read, without
+ * requiring to wait for the entire body to be processed. The response
+ * body can then be read directly from the {@link Stream}.
+ *
+ * @apiNote To ensure that all resources associated with the
+ * corresponding exchange are properly released the caller must
+ * ensure to either read all lines until the stream is exhausted,
+ * or call {@link Stream#close} if it is unable or unwilling to do so.
+ * Calling {@code close} before exhausting the stream may cause
+ * the underlying HTTP connection to be closed and prevent it
+ * from being reused for subsequent operations.
+ *
+ * @param charset the character set to use when converting bytes to characters
+ * @return a body subscriber that streams the response body as a
+ * {@link Stream Stream<String>}.
+ *
+ * @see BufferedReader#lines()
+ */
+ public static BodySubscriber<Stream<String>> asLines(Charset charset) {
+ return ResponseSubscribers.createLineStream(charset);
+ }
+
+ /**
+ * Returns a response subscriber which discards the response body. The
+ * supplied value is the value that will be returned from
+ * {@link HttpResponse#body()}.
+ *
+ * @param <U> The type of the response body
+ * @param value the value to return from HttpResponse.body(), may be {@code null}
+ * @return a {@code BodySubscriber}
+ */
+ public static <U> BodySubscriber<U> replace(U value) {
+ return new ResponseSubscribers.NullSubscriber<>(Optional.ofNullable(value));
+ }
+
+ /**
+ * Returns a response subscriber which discards the response body.
+ *
+ * @return a response body subscriber
+ */
+ public static BodySubscriber<Void> discard() {
+ return new ResponseSubscribers.NullSubscriber<>(Optional.ofNullable(null));
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} which buffers data before delivering
+ * it to the given downstream subscriber. The subscriber guarantees to
+ * deliver {@code buffersize} bytes of data to each invocation of the
+ * downstream's {@linkplain #onNext(Object) onNext} method, except for
+ * the final invocation, just before {@linkplain #onComplete() onComplete}
+ * is invoked. The final invocation of {@code onNext} may contain fewer
+ * than {@code buffersize} bytes.
+ *
+ * <p> The returned subscriber delegates its {@link #getBody()} method
+ * to the downstream subscriber.
+ *
+ * @param downstream the downstream subscriber
+ * @param bufferSize the buffer size
+ * @return a buffering body subscriber
+ * @throws IllegalArgumentException if {@code bufferSize <= 0}
+ */
+ public static <T> BodySubscriber<T> buffering(BodySubscriber<T> downstream,
+ int bufferSize) {
+ if (bufferSize <= 0)
+ throw new IllegalArgumentException("must be greater than 0");
+ return new BufferingSubscriber<T>(downstream, bufferSize);
+ }
+
+ /**
+ * Returns a {@code BodySubscriber} whose response body is mapped
+ * using the supplied mapping function from one type {@code <T>} to
+ * another type {@code <U>}. The mapping function is executed
+ * using the {@link Executor} of the sending client and can
+ * therefore be used to map any response body type, including
+ * blocking {@link java.io.InputStream}s as shown in the following
+ * example which uses a well-known JSON parser to convert an {@code InputStream}
+ * into any annotated Java object type.
+ * <p>
+ * <b>Example usage</b>
+ * <p> <pre> {@code
+ * public static <W> BodySubscriber<W> asJSON(Class<W> targetType) {
+ * BodySubscriber<InputStream> upstream = BodySubscriber.asInputStream();
+ *
+ * BodySubscriber<W> downstream = mappedFrom(
+ * upstream,
+ * (InputStream is) -> {
+ * try (InputStream stream = is) {
+ * ObjectMapper objectMapper = new ObjectMapper();
+ * W result = objectMapper.readValue(stream, targetType);
+ * return result;
+ * } catch (IOException e) {
+ * throw new UncheckedIOException(e);
+ * }
+ * });
+ * return downstream;
+ * }
+ * }</pre>
+ *
+ * @param <T> the type of the body subscriber to be mapped
+ * @param <U> the type of the body subscriber returned
+ * @param upstream the body subscriber to be mapped
+ * @param mapper the mapping function
+ * @return a mapped body subscriber
+ */
+ public static <T,U> BodySubscriber<U> mappedFrom(
+ BodySubscriber<T> upstream,
+ Function<T, U> mapper)
+ {
+ return new ResponseSubscribers.MappedSubscriber<T, U>(upstream, mapper);
+ }
+ }
+}