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This package contains examples of how to use drasyl.
There is a newer version: 0.10.0
/*
 * Copyright (c) 2020-2021 Heiko Bornholdt and Kevin Röbert
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
 * OR OTHER DEALINGS IN THE SOFTWARE.
 */
package org.drasyl.example.time;

import org.drasyl.annotation.NonNull;
import org.drasyl.node.DrasylConfig;
import org.drasyl.node.DrasylException;
import org.drasyl.node.DrasylNode;
import org.drasyl.node.event.Event;
import org.drasyl.node.event.MessageEvent;
import org.drasyl.node.event.NodeOnlineEvent;

import java.nio.file.Path;
import java.util.Date;
import java.util.concurrent.CompletableFuture;

import static org.drasyl.example.time.TimeServer.UNIX_TIME_OFFSET;

/**
 * Starts a node which sends an empty message to the given address. Expects a reply with the time in
 * seconds since midnight on January first 1900. Based on the Time
 * Protocol.
 *
 * @see TimeServer
 */
@SuppressWarnings({
        "java:S106",
        "java:S112",
        "java:S125",
        "java:S126",
        "java:S2096",
        "java:S2143"
})
public class TimeClient extends DrasylNode {
    private static final String IDENTITY = System.getProperty("identity", "time-client.identity");
    private final CompletableFuture online = new CompletableFuture<>();

    protected TimeClient(final DrasylConfig config) throws DrasylException {
        super(config);
    }

    @Override
    public void onEvent(final @NonNull Event event) {
        if (event instanceof NodeOnlineEvent) {
            online.complete(null);
        }
        else if (event instanceof MessageEvent && ((MessageEvent) event).getPayload() instanceof Integer) {
            final long payload = Integer.toUnsignedLong((int) ((MessageEvent) event).getPayload());
            final long currentTimeMillis = (payload - UNIX_TIME_OFFSET) * 1000L;
            System.out.println(new Date(currentTimeMillis));
            shutdown().thenRun(() -> System.exit(0));
        }
    }

    public static void main(final String[] args) throws DrasylException {
        if (args.length != 1) {
            System.err.println("Please provide TimeServer address as first argument.");
            System.exit(1);
        }
        final String recipient = args[0];

        final DrasylConfig config = DrasylConfig.newBuilder()
                .identityPath(Path.of(IDENTITY))
                .build();
        final TimeClient node = new TimeClient(config);

        node.start().toCompletableFuture().join();
        node.online.join();
        System.out.println("TimeClient started");

        node.send(recipient, null).exceptionally(e -> {
            throw new RuntimeException("Unable to process message.", e);
        });
    }
}