ClassicToAsyncResponseConsumer.java
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
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*/
package org.apache.hc.core5.http.nio.support.classic;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.hc.core5.annotation.Experimental;
import org.apache.hc.core5.concurrent.FutureCallback;
import org.apache.hc.core5.function.Supplier;
import org.apache.hc.core5.http.ClassicHttpResponse;
import org.apache.hc.core5.http.EntityDetails;
import org.apache.hc.core5.http.Header;
import org.apache.hc.core5.http.HttpEntity;
import org.apache.hc.core5.http.HttpException;
import org.apache.hc.core5.http.HttpResponse;
import org.apache.hc.core5.http.io.entity.AbstractHttpEntity;
import org.apache.hc.core5.http.io.support.ClassicResponseBuilder;
import org.apache.hc.core5.http.nio.AsyncResponseConsumer;
import org.apache.hc.core5.http.nio.CapacityChannel;
import org.apache.hc.core5.http.protocol.HttpContext;
import org.apache.hc.core5.io.Closer;
import org.apache.hc.core5.util.Args;
import org.apache.hc.core5.util.Asserts;
import org.apache.hc.core5.util.Timeout;
/**
* @since 5.4
*/
@Experimental
public class ClassicToAsyncResponseConsumer implements AsyncResponseConsumer<Void> {
static class ResponseData {
final HttpResponse head;
final EntityDetails entityDetails;
ResponseData(final HttpResponse head,
final EntityDetails entityDetails) {
this.head = head;
this.entityDetails = entityDetails;
}
}
private final int initialBufferSize;
private final Timeout timeout;
private final CountDownLatch countDownLatch;
private final AtomicReference<ResponseData> responseRef;
private final AtomicReference<FutureCallback<Void>> callbackRef;
private final AtomicReference<SharedInputBuffer> bufferRef;
private final AtomicReference<Exception> exceptionRef;
public ClassicToAsyncResponseConsumer(final int initialBufferSize, final Timeout timeout) {
this.initialBufferSize = Args.positive(initialBufferSize, "Initial buffer size");
this.timeout = timeout;
this.countDownLatch = new CountDownLatch(1);
this.responseRef = new AtomicReference<>();
this.callbackRef = new AtomicReference<>();
this.bufferRef = new AtomicReference<>();
this.exceptionRef = new AtomicReference<>();
}
public ClassicToAsyncResponseConsumer(final Timeout timeout) {
this(ClassicToAsyncSupport.INITIAL_BUF_SIZE, timeout);
}
void propagateException() throws IOException {
final Exception ex = exceptionRef.getAndSet(null);
if (ex != null) {
ClassicToAsyncSupport.rethrow(ex);
}
}
void fireComplete() throws IOException {
final FutureCallback<Void> callback = callbackRef.getAndSet(null);
if (callback != null) {
callback.completed(null);
}
}
public ClassicHttpResponse blockWaiting() throws IOException, InterruptedException {
if (timeout == null) {
countDownLatch.await();
} else {
if (!countDownLatch.await(timeout.getDuration(), timeout.getTimeUnit())) {
throw new InterruptedIOException("Timeout blocked waiting for input (" + timeout + ")");
}
}
propagateException();
final ResponseData r = responseRef.getAndSet(null);
Asserts.notNull(r, "HTTP response is missing");
final SharedInputBuffer inputBuffer = bufferRef.get();
return ClassicResponseBuilder.copy(r.head)
.setEntity(r.entityDetails != null ?
new IncomingHttpEntity(new InternalInputStream(inputBuffer), r.entityDetails) :
null)
.build();
}
@Override
public void consumeResponse(final HttpResponse asyncResponse,
final EntityDetails entityDetails,
final HttpContext context,
final FutureCallback<Void> resultCallback) throws HttpException, IOException {
callbackRef.set(resultCallback);
final ResponseData responseData = new ResponseData(asyncResponse, entityDetails);
responseRef.set(responseData);
if (entityDetails != null) {
bufferRef.set(new SharedInputBuffer(initialBufferSize));
} else {
fireComplete();
}
countDownLatch.countDown();
}
@Override
public void informationResponse(final HttpResponse response,
final HttpContext context) throws HttpException, IOException {
}
@Override
public final void updateCapacity(final CapacityChannel capacityChannel) throws IOException {
final SharedInputBuffer buffer = bufferRef.get();
if (buffer != null) {
buffer.updateCapacity(capacityChannel);
}
}
@Override
public final void consume(final ByteBuffer src) throws IOException {
final SharedInputBuffer buffer = bufferRef.get();
if (buffer != null) {
buffer.fill(src);
}
}
@Override
public final void streamEnd(final List<? extends Header> trailers) throws HttpException, IOException {
final SharedInputBuffer buffer = bufferRef.get();
if (buffer != null) {
buffer.markEndStream();
}
}
@Override
public final void failed(final Exception cause) {
try {
exceptionRef.set(cause);
} finally {
countDownLatch.countDown();
}
}
@Override
public void releaseResources() {
}
class InternalInputStream extends InputStream {
private final SharedInputBuffer buffer;
InternalInputStream(final SharedInputBuffer buffer) {
super();
Args.notNull(buffer, "Input buffer");
this.buffer = buffer;
}
@Override
public int available() throws IOException {
propagateException();
return this.buffer.length();
}
@Override
public int read(final byte[] b, final int off, final int len) throws IOException {
propagateException();
if (len == 0) {
return 0;
}
final int bytesRead = this.buffer.read(b, off, len, timeout);
if (bytesRead == -1) {
fireComplete();
}
return bytesRead;
}
@Override
public int read(final byte[] b) throws IOException {
propagateException();
if (b == null) {
return 0;
}
final int bytesRead = this.buffer.read(b, 0, b.length, timeout);
if (bytesRead == -1) {
fireComplete();
}
return bytesRead;
}
@Override
public int read() throws IOException {
propagateException();
final int b = this.buffer.read(timeout);
if (b == -1) {
fireComplete();
}
return b;
}
@Override
public void close() throws IOException {
// read and discard the remainder of the message
final byte[] tmp = new byte[1024];
do {
/* empty */
} while (read(tmp) >= 0);
super.close();
}
}
static class IncomingHttpEntity implements HttpEntity {
private final InputStream content;
private final EntityDetails entityDetails;
IncomingHttpEntity(final InputStream content, final EntityDetails entityDetails) {
this.content = content;
this.entityDetails = entityDetails;
}
@Override
public boolean isRepeatable() {
return false;
}
@Override
public boolean isChunked() {
return entityDetails.isChunked();
}
@Override
public long getContentLength() {
return entityDetails.getContentLength();
}
@Override
public String getContentType() {
return entityDetails.getContentType();
}
@Override
public String getContentEncoding() {
return entityDetails.getContentEncoding();
}
@Override
public InputStream getContent() throws IOException, IllegalStateException {
return content;
}
@Override
public boolean isStreaming() {
return content != null;
}
@Override
public void writeTo(final OutputStream outStream) throws IOException {
AbstractHttpEntity.writeTo(this, outStream);
}
@Override
public Supplier<List<? extends Header>> getTrailers() {
return null;
}
@Override
public Set<String> getTrailerNames() {
return Collections.emptySet();
}
@Override
public void close() throws IOException {
Closer.close(content);
}
@Override
public String toString() {
return entityDetails.toString();
}
}
}