1 /* 2 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"). 5 * You may not use this file except in compliance with the License. 6 * A copy of the License is located at 7 * 8 * http://aws.amazon.com/apache2.0 9 * 10 * or in the "license" file accompanying this file. This file is distributed 11 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 12 * express or implied. See the License for the specific language governing 13 * permissions and limitations under the License. 14 */ 15 16 package software.amazon.awssdk.core.internal.async; 17 18 import java.nio.ByteBuffer; 19 import java.util.concurrent.CompletableFuture; 20 import software.amazon.awssdk.annotations.SdkInternalApi; 21 import software.amazon.awssdk.core.ResponseInputStream; 22 import software.amazon.awssdk.core.SdkResponse; 23 import software.amazon.awssdk.core.async.AsyncResponseTransformer; 24 import software.amazon.awssdk.core.async.SdkPublisher; 25 import software.amazon.awssdk.utils.async.InputStreamSubscriber; 26 27 /** 28 * A {@link AsyncResponseTransformer} that allows performing blocking reads on the response data. 29 * <p> 30 * Created with {@link AsyncResponseTransformer#toBlockingInputStream()}. 31 */ 32 @SdkInternalApi 33 public class InputStreamResponseTransformer<ResponseT extends SdkResponse> 34 implements AsyncResponseTransformer<ResponseT, ResponseInputStream<ResponseT>> { 35 36 private volatile CompletableFuture<ResponseInputStream<ResponseT>> future; 37 private volatile ResponseT response; 38 39 @Override prepare()40 public CompletableFuture<ResponseInputStream<ResponseT>> prepare() { 41 CompletableFuture<ResponseInputStream<ResponseT>> result = new CompletableFuture<>(); 42 this.future = result; 43 return result; 44 } 45 46 @Override onResponse(ResponseT response)47 public void onResponse(ResponseT response) { 48 this.response = response; 49 } 50 51 @Override onStream(SdkPublisher<ByteBuffer> publisher)52 public void onStream(SdkPublisher<ByteBuffer> publisher) { 53 InputStreamSubscriber inputStreamSubscriber = new InputStreamSubscriber(); 54 publisher.subscribe(inputStreamSubscriber); 55 future.complete(new ResponseInputStream<>(response, inputStreamSubscriber)); 56 } 57 58 @Override exceptionOccurred(Throwable error)59 public void exceptionOccurred(Throwable error) { 60 future.completeExceptionally(error); 61 } 62 } 63