/*

 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * 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,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import java.io.IOException;

import java.io.PrintStream;

import java.net.http.HttpClient;

import java.net.http.HttpRequest;

import java.net.http.HttpResponse;

import java.net.http.HttpResponse.BodyHandler;

import java.util.Collections;

import java.util.List;

import java.util.concurrent.CopyOnWriteArrayList;

import java.util.concurrent.Flow;

import java.util.regex.Pattern;

/*

 * THE CONTENTS OF THIS FILE HAVE TO BE IN SYNC WITH THE EXAMPLES USED IN THE

 * JAVADOC.

 *

 * @test

 * @compile JavadocExamples.java

 */

public class JavadocExamples {

    HttpRequest request = null;

    HttpClient client = null;

    Pattern p = null;

    /**

     * @apiNote This method can be used as an adapter between a {@code

     * BodySubscriber} and a text based {@code Flow.Subscriber} that parses

     * text line by line.

     *

     * <p> For example:

     * <pre> {@code  // A PrintSubscriber that implements Flow.Subscriber<String>

     *  // and print lines received by onNext() on System.out

     *  PrintSubscriber subscriber = new PrintSubscriber(System.out);

     *  client.sendAsync(request, BodyHandler.fromLineSubscriber(subscriber))

     *      .thenApply(HttpResponse::statusCode)

     *      .thenAccept((status) -> {

     *          if (status != 200) {

     *              System.err.printf("ERROR: %d status received%n", status);

     *          }

     *      }); }</pre>

     */

    void fromLineSubscriber1() {

         // A PrintSubscriber that implements Flow.Subscriber<String>

         // and print lines received by onNext() on System.out

         PrintSubscriber subscriber = new PrintSubscriber(System.out);

         client.sendAsync(request, BodyHandler.fromLineSubscriber(subscriber))

                 .thenApply(HttpResponse::statusCode)

                 .thenAccept((status) -> {

                     if (status != 200) {

                         System.err.printf("ERROR: %d status received%n", status);

                     }

                 });

    }

    /**

     * @apiNote This method can be used as an adapter between a {@code

     * BodySubscriber} and a text based {@code Flow.Subscriber} that parses

     * text line by line.

     *

     * <p> For example:

     * <pre> {@code  // A LineParserSubscriber that implements Flow.Subscriber<String>

     *  // and accumulates lines that match a particular pattern

     *  Pattern pattern = ...;

     *  LineParserSubscriber subscriber = new LineParserSubscriber(pattern);

     *  HttpResponse<List<String>> response = client.send(request,

     *  if (response.statusCode() != 200) {

     *      System.err.printf("ERROR: %d status received%n", response.statusCode());

     *  } }</pre>

     *

     */

    void fromLineSubscriber2() throws IOException, InterruptedException {

        // A LineParserSubscriber that implements Flow.Subscriber<String>

        // and accumulates lines that match a particular pattern

        Pattern pattern = p;

        LineParserSubscriber subscriber = new LineParserSubscriber(pattern);

        HttpResponse<List<String>> response = client.send(request,

                BodyHandler.fromLineSubscriber(subscriber, s -> s.getMatchingLines(), "\n"));

        if (response.statusCode() != 200) {

            System.err.printf("ERROR: %d status received%n", response.statusCode());

        }

    }

    static final class PrintSubscriber implements Flow.Subscriber<String> {

        final PrintStream out;

        PrintSubscriber(PrintStream out) {

            this.out = out;

        }

        @Override

        public void onSubscribe(Flow.Subscription subscription) {

            subscription.request(Long.MAX_VALUE);

        }

        @Override

        public void onNext(String item) {

            out.println(item);

        }

        @Override

        public void onError(Throwable throwable) {

            throwable.printStackTrace();

        }

        @Override

        public void onComplete() {

        }

    }

    static final class LineParserSubscriber implements Flow.Subscriber<String> {

        final Pattern pattern;

        final CopyOnWriteArrayList<String> matches = new CopyOnWriteArrayList<>();

        LineParserSubscriber(Pattern pattern) {

            this.pattern = pattern;

        }

        @Override

        public void onSubscribe(Flow.Subscription subscription) {

            subscription.request(Long.MAX_VALUE);

        }

        @Override

        public void onNext(String item) {

            if (pattern.matcher(item).matches()) {

                matches.add(item);

            }

        }

        @Override

        public void onError(Throwable throwable) {

            throwable.printStackTrace();

        }

        @Override

        public void onComplete() {

        }

        public List<String> getMatchingLines() {

            return Collections.unmodifiableList(matches);

        }

    }

}