App.java

/*
 * Copyright (c) 2012, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0, which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.glassfish.jersey.examples.helloworld.jaxrs;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.URI;

import javax.ws.rs.core.UriBuilder;
import javax.ws.rs.ext.RuntimeDelegate;

import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;

/**
 * Hello world application using only the standard JAX-RS API and lightweight HTTP server bundled in JDK.
 *
 * @author Martin Matula
 */
public class App {

    /**
     * Starts the lightweight HTTP server serving the JAX-RS application.
     *
     * @return new instance of the lightweight HTTP server
     * @throws IOException
     */
    static HttpServer startServer() throws IOException {
        // create a new server listening at port 8080
        final HttpServer server = HttpServer.create(new InetSocketAddress(getBaseURI().getPort()), 0);
        Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {
            @Override
            public void run() {
                server.stop(0);
            }
        }));

        // create a handler wrapping the JAX-RS application
        HttpHandler handler = RuntimeDelegate.getInstance().createEndpoint(new JaxRsApplication(), HttpHandler.class);

        // map JAX-RS handler to the server root
        server.createContext(getBaseURI().getPath(), handler);

        // start the server
        server.start();

        return server;
    }

    public static void main(String[] args) throws IOException, InterruptedException {
        System.out.println("\"Hello World\" Jersey Example Application");

        startServer();

        System.out.println("Application started.\n"
                + "Try accessing " + getBaseURI() + "helloworld in the browser.\n"
                + "CTRL + C to stop the application...\n");

        Thread.currentThread().join();
    }

    private static int getPort(int defaultPort) {
        final String port = System.getProperty("jersey.config.test.container.port");
        if (null != port) {
            try {
                return Integer.parseInt(port);
            } catch (NumberFormatException e) {
                System.out.println("Value of jersey.config.test.container.port property"
                        + " is not a valid positive integer [" + port + "]."
                        + " Reverting to default [" + defaultPort + "].");
            }
        }
        return defaultPort;
    }

    /**
     * Gets base {@link URI}.
     *
     * @return base {@link URI}.
     */
    public static URI getBaseURI() {
        return UriBuilder.fromUri("http://localhost/").port(getPort(8080)).build();
    }
}