AsyncRequestExecutionExample

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 * 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
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 * KIND, either express or implied.  See the License for the
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 * under the License.
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package org.apache.hc.core5.http.examples;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import org.apache.hc.core5.concurrent.FutureCallback;
import org.apache.hc.core5.http.HttpConnection;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.HttpRequest;
import org.apache.hc.core5.http.HttpResponse;
import org.apache.hc.core5.http.Message;
import org.apache.hc.core5.http.impl.Http1StreamListener;
import org.apache.hc.core5.http.impl.bootstrap.AsyncRequesterBootstrap;
import org.apache.hc.core5.http.impl.bootstrap.HttpAsyncRequester;
import org.apache.hc.core5.http.message.RequestLine;
import org.apache.hc.core5.http.message.StatusLine;
import org.apache.hc.core5.http.nio.entity.StringAsyncEntityConsumer;
import org.apache.hc.core5.http.nio.support.AsyncRequestBuilder;
import org.apache.hc.core5.http.nio.support.BasicResponseConsumer;
import org.apache.hc.core5.io.CloseMode;
import org.apache.hc.core5.reactor.IOReactorConfig;
import org.apache.hc.core5.util.Timeout;

/**
 * Example of asynchronous HTTP/1.1 request execution.
 */
public class AsyncRequestExecutionExample {

    public static void main(final String[] args) throws Exception {

        final IOReactorConfig ioReactorConfig = IOReactorConfig.custom()
                .setSoTimeout(5, TimeUnit.SECONDS)
                .build();

        // Create and start requester
        final HttpAsyncRequester requester = AsyncRequesterBootstrap.bootstrap()
                .setIOReactorConfig(ioReactorConfig)
                .setStreamListener(new Http1StreamListener() {

                    @Override
                    public void onRequestHead(final HttpConnection connection, final HttpRequest request) {
                        System.out.println(connection.getRemoteAddress() + " " + new RequestLine(request));
                    }

                    @Override
                    public void onResponseHead(final HttpConnection connection, final HttpResponse response) {
                        System.out.println(connection.getRemoteAddress() + " " + new StatusLine(response));
                    }

                    @Override
                    public void onExchangeComplete(final HttpConnection connection, final boolean keepAlive) {
                        if (keepAlive) {
                            System.out.println(connection.getRemoteAddress() + " exchange completed (connection kept alive)");
                        } else {
                            System.out.println(connection.getRemoteAddress() + " exchange completed (connection closed)");
                        }
                    }

                })
                .create();

        Runtime.getRuntime().addShutdownHook(new Thread() {
            @Override
            public void run() {
                System.out.println("HTTP requester shutting down");
                requester.close(CloseMode.GRACEFUL);
            }
        });
        requester.start();

        final HttpHost target = new HttpHost("httpbin.org");
        final String[] requestUris = new String[] {"/", "/ip", "/user-agent", "/headers"};

        final CountDownLatch latch = new CountDownLatch(requestUris.length);
        for (final String requestUri: requestUris) {
            requester.execute(
                    AsyncRequestBuilder.get()
                            .setHttpHost(target)
                            .setPath(requestUri)
                            .build(),
                    new BasicResponseConsumer<>(new StringAsyncEntityConsumer()),
                    Timeout.ofSeconds(5),
                    new FutureCallback<Message<HttpResponse, String>>() {

                        @Override
                        public void completed(final Message<HttpResponse, String> message) {
                            final HttpResponse response = message.getHead();
                            final String body = message.getBody();
                            System.out.println(requestUri + "->" + response.getCode());
                            System.out.println(body);
                            latch.countDown();
                        }

                        @Override
                        public void failed(final Exception ex) {
                            System.out.println(requestUri + "->" + ex);
                            latch.countDown();
                        }

                        @Override
                        public void cancelled() {
                            System.out.println(requestUri + " cancelled");
                            latch.countDown();
                        }

                    });
        }

        latch.await();
        System.out.println("Shutting down I/O reactor");
        requester.initiateShutdown();
    }

}