JsonTokenEventResponseExample.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,
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 * 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
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package org.apache.hc.core5.jackson2.http.examples;

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

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.databind.ObjectMapper;

import org.apache.hc.core5.concurrent.FutureCallback;
import org.apache.hc.core5.http.impl.bootstrap.AsyncRequesterBootstrap;
import org.apache.hc.core5.http.impl.bootstrap.HttpAsyncRequester;
import org.apache.hc.core5.http.protocol.HttpCoreContext;
import org.apache.hc.core5.io.CloseMode;
import org.apache.hc.core5.jackson2.JsonTokenEventHandler;
import org.apache.hc.core5.jackson2.http.AsyncJsonClientPipeline;
import org.apache.hc.core5.reactor.IOReactorConfig;
import org.apache.hc.core5.util.Timeout;

public class JsonTokenEventResponseExample {

    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)
                .create();

        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
            System.out.println("HTTP requester shutting down");
            requester.close(CloseMode.GRACEFUL);
        }));
        requester.start();

        final URI uri = URI.create("http://httpbin.org/get");

        System.out.println("Executing GET " + uri);
        final JsonFactory factory = new JsonFactory();
        final ObjectMapper objectMapper = new ObjectMapper(factory);

        final CountDownLatch latch = new CountDownLatch(1);
        requester.execute(
                AsyncJsonClientPipeline.assemble(objectMapper)
                        .request()
                        .get(uri)
                        .response()
                        .asEvents(
                                response -> System.out.println("Response status: " + response.getCode()),
                                error -> System.out.println("Error: " + error),
                                new JsonTokenEventHandler() {

                                    @Override
                                    public void objectStart() {
                                        System.out.print("object start/");
                                    }

                                    @Override
                                    public void objectEnd() {
                                        System.out.print("object end/");
                                    }

                                    @Override
                                    public void arrayStart() {
                                        System.out.print("array start/");
                                    }

                                    @Override
                                    public void arrayEnd() {
                                        System.out.print("array end/");
                                    }

                                    @Override
                                    public void field(final String name) {
                                        System.out.print(name + "=");
                                    }

                                    @Override
                                    public void embeddedObject(final Object object) {
                                        System.out.print(object + "/");
                                    }

                                    @Override
                                    public void value(final String value) {
                                        System.out.print("\"" + value + "\"/");
                                    }

                                    @Override
                                    public void value(final int value) {
                                        System.out.print(value + "/");
                                    }

                                    @Override
                                    public void value(final long value) {
                                        System.out.print(value + "/");
                                    }

                                    @Override
                                    public void value(final double value) {
                                        System.out.print(value + "/");
                                    }

                                    @Override
                                    public void value(final boolean value) {
                                        System.out.print(value + "/");
                                    }

                                    @Override
                                    public void valueNull() {
                                        System.out.print("null/");
                                    }

                                    @Override
                                    public void endOfStream() {
                                        System.out.println("stream end/");
                                    }

                                })
                        .result(new FutureCallback<Void>() {

                            @Override
                            public void completed(final Void input) {
                                System.out.println("Object received");
                                latch.countDown();
                            }

                            @Override
                            public void failed(final Exception ex) {
                                ex.printStackTrace(System.out);
                                latch.countDown();
                            }

                            @Override
                            public void cancelled() {
                                latch.countDown();
                            }

                        })
                        .create(),
                Timeout.ofMinutes(1),
                HttpCoreContext.create());

        latch.await();

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

}