gistfile1.txt

import java.io.*;
import javax.net.ssl.*;

/*
 * This example demostrates how to use a SSLSocket as client to
 * send a HTTP request and get response from an HTTPS server.
 * It assumes that the client is not behind a firewall
 * https://docs.oracle.com/javase/10/security/sample-code-illustrating-secure-socket-connection-client-and-server.htm
 *
 * Usage: 
 * java -Djavax.net.ssl.trustStorePassword="password" \
 *     -Djavax.net.ssl.trustStore=myTrustStore \
 *     -Djavax.net.ssl.keyStorePassword="password" \
 *     -Djavax.net.ssl.keyStore=myKeyStore.jks \
 *     SSLSocketClient <IP> <port>
 */

public class SSLSocketClient {

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

        String host = null;
        int port = -1;
        for (int i = 0; i < args.length; i++)
            System.out.println(args[i]);

        if (args.length < 2) {
            System.out.println(
                "USAGE: java SSLSocketClient " +
                "host port");
            System.exit(-1);
        }

        try {
            host = args[0];
            port = Integer.parseInt(args[1]);
        } catch (IllegalArgumentException e) {
             System.out.println("USAGE: java SSLSocketClient " +
                 "host port");
             System.exit(-1);
        }

        try {
            SSLSocketFactory factory =
                (SSLSocketFactory)SSLSocketFactory.getDefault();
            SSLSocket socket =
                (SSLSocket)factory.createSocket(host, port);

            /*
             * send http request
             *
             * Before any application data is sent or received, the
             * SSL socket will do SSL handshaking first to set up
             * the security attributes.
             *
             * SSL handshaking can be initiated by either flushing data
             * down the pipe, or by starting the handshaking by hand.
             *
             * Handshaking is started manually in this example because
             * PrintWriter catches all IOExceptions (including
             * SSLExceptions), sets an internal error flag, and then
             * returns without rethrowing the exception.
             *
             * Unfortunately, this means any error messages are lost,
             * which caused lots of confusion for others using this
             * code.  The only way to tell there was an error is to call
             * PrintWriter.checkError().
             */
            socket.startHandshake();

            PrintWriter out = new PrintWriter(
                                  new BufferedWriter(
                                  new OutputStreamWriter(
                                  socket.getOutputStream())));

            out.println("GET / HTTP/1.0");
            out.println();
            out.flush();

            /*
             * Make sure there were no surprises
             */
            if (out.checkError())
                System.out.println(
                    "SSLSocketClient:  java.io.PrintWriter error");

            /* read response */
            BufferedReader in = new BufferedReader(
                                    new InputStreamReader(
                                    socket.getInputStream()));

            String inputLine;
            while ((inputLine = in.readLine()) != null)
                System.out.println(inputLine);

            in.close();
            out.close();
            socket.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}