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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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
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*
* 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,
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*
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package jdk.internal.net.http;
import java.io.IOException;
import java.net.http.HttpClient;
import java.net.http.HttpResponse;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executor;
import jdk.internal.net.http.common.Logger;
import jdk.internal.net.http.common.MinimalFuture;
import jdk.internal.net.http.common.Utils;
import static java.net.http.HttpClient.Version.HTTP_1_1;
/**
* Splits request so that headers and body can be sent separately with optional
* (multiple) responses in between (e.g. 100 Continue). Also request and
* response always sent/received in different calls.
*
* Synchronous and asynchronous versions of each method are provided.
*
* Separate implementations of this class exist for HTTP/1.1 and HTTP/2
* Http1Exchange (HTTP/1.1)
* Stream (HTTP/2)
*
* These implementation classes are where work is allocated to threads.
*/
abstract class ExchangeImpl<T> {
private static final Logger debug =
Utils.getDebugLogger("ExchangeImpl"::toString, Utils.DEBUG);
final Exchange<T> exchange;
ExchangeImpl(Exchange<T> e) {
// e == null means a http/2 pushed stream
this.exchange = e;
}
final Exchange<T> getExchange() {
return exchange;
}
HttpClient client() {
return exchange.client();
}
/**
* Returns the {@link HttpConnection} instance to which this exchange is
* assigned.
*/
abstract HttpConnection connection();
/**
* Initiates a new exchange and assigns it to a connection if one exists
* already. connection usually null.
*/
static <U> CompletableFuture<? extends ExchangeImpl<U>>
get(Exchange<U> exchange, HttpConnection connection)
{
if (exchange.version() == HTTP_1_1) {
if (debug.on())
debug.log("get: HTTP/1.1: new Http1Exchange");
return createHttp1Exchange(exchange, connection);
} else {
Http2ClientImpl c2 = exchange.client().client2(); // #### improve
HttpRequestImpl request = exchange.request();
CompletableFuture<Http2Connection> c2f = c2.getConnectionFor(request, exchange);
if (debug.on())
debug.log("get: Trying to get HTTP/2 connection");
// local variable required here; see JDK-8223553
CompletableFuture<CompletableFuture<? extends ExchangeImpl<U>>> fxi =
c2f.handle((h2c, t) -> createExchangeImpl(h2c, t, exchange, connection));
return fxi.thenCompose(x->x);
}
}
private static <U> CompletableFuture<? extends ExchangeImpl<U>>
createExchangeImpl(Http2Connection c,
Throwable t,
Exchange<U> exchange,
HttpConnection connection)
{
if (debug.on())
debug.log("handling HTTP/2 connection creation result");
boolean secure = exchange.request().secure();
if (t != null) {
if (debug.on())
debug.log("handling HTTP/2 connection creation failed: %s",
(Object)t);
t = Utils.getCompletionCause(t);
if (t instanceof Http2Connection.ALPNException) {
Http2Connection.ALPNException ee = (Http2Connection.ALPNException)t;
AbstractAsyncSSLConnection as = ee.getConnection();
if (debug.on())
debug.log("downgrading to HTTP/1.1 with: %s", as);
CompletableFuture<? extends ExchangeImpl<U>> ex =
createHttp1Exchange(exchange, as);
return ex;
} else {
if (debug.on())
debug.log("HTTP/2 connection creation failed "
+ "with unexpected exception: %s", (Object)t);
return MinimalFuture.failedFuture(t);
}
}
if (secure && c== null) {
if (debug.on())
debug.log("downgrading to HTTP/1.1 ");
CompletableFuture<? extends ExchangeImpl<U>> ex =
createHttp1Exchange(exchange, null);
return ex;
}
if (c == null) {
// no existing connection. Send request with HTTP 1 and then
// upgrade if successful
if (debug.on())
debug.log("new Http1Exchange, try to upgrade");
return createHttp1Exchange(exchange, connection)
.thenApply((e) -> {
exchange.h2Upgrade();
return e;
});
} else {
if (debug.on()) debug.log("creating HTTP/2 streams");
Stream<U> s = c.createStream(exchange);
CompletableFuture<? extends ExchangeImpl<U>> ex = MinimalFuture.completedFuture(s);
return ex;
}
}
private static <T> CompletableFuture<Http1Exchange<T>>
createHttp1Exchange(Exchange<T> ex, HttpConnection as)
{
try {
return MinimalFuture.completedFuture(new Http1Exchange<>(ex, as));
} catch (Throwable e) {
return MinimalFuture.failedFuture(e);
}
}
// Called for 204 response - when no body is permitted
void nullBody(HttpResponse<T> resp, Throwable t) {
// only needed for HTTP/1.1 to close the connection
// or return it to the pool
}
/* The following methods have separate HTTP/1.1 and HTTP/2 implementations */
abstract CompletableFuture<ExchangeImpl<T>> sendHeadersAsync();
/** Sends a request body, after request headers have been sent. */
abstract CompletableFuture<ExchangeImpl<T>> sendBodyAsync();
abstract CompletableFuture<T> readBodyAsync(HttpResponse.BodyHandler<T> handler,
boolean returnConnectionToPool,
Executor executor);
/**
* Ignore/consume the body.
*/
abstract CompletableFuture<Void> ignoreBody();
/** Gets the response headers. Completes before body is read. */
abstract CompletableFuture<Response> getResponseAsync(Executor executor);
/** Cancels a request. Not currently exposed through API. */
abstract void cancel();
/**
* Cancels a request with a cause. Not currently exposed through API.
*/
abstract void cancel(IOException cause);
/**
* Called when the exchange is released, so that cleanup actions may be
* performed - such as deregistering callbacks.
* Typically released is called during upgrade, when an HTTP/2 stream
* takes over from an Http1Exchange, or when a new exchange is created
* during a multi exchange before the final response body was received.
*/
abstract void released();
/**
* Called when the exchange is completed, so that cleanup actions may be
* performed - such as deregistering callbacks.
* Typically, completed is called at the end of the exchange, when the
* final response body has been received (or an error has caused the
* completion of the exchange).
*/
abstract void completed();
/**
* Returns true if this exchange was canceled.
* @return true if this exchange was canceled.
*/
abstract boolean isCanceled();
/**
* Returns the cause for which this exchange was canceled, if available.
* @return the cause for which this exchange was canceled, if available.
*/
abstract Throwable getCancelCause();
}