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import java.net.*;
import java.io.*;
import javax.net.ssl.*;
/* java SSLSocketClient taken from
* https://docs.oracle.com/javase/10/security/sample-code-illustrating-secure-socket-connection-client-and-server.htm
* License: Unknown, not GPLv2
*/
/*
* This example demonstrates 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.
* The handshake doesn't include any ALPN protocols. See
* https://docs.oracle.com/javase/8/docs/technotes/guides/security/jsse/alpn.html
* for more documentation.
*/
public class SSLSocketClient {
public static void main(String[] args) throws Exception {
String host=args[0];
if ( args == null || args.length == 0 || host.trim().isEmpty() ) {
System.out.println("You need to supply a valid hostname");
} else {
try {
SSLSocketFactory factory =
(SSLSocketFactory)SSLSocketFactory.getDefault();
SSLSocket socket =
(SSLSocket)factory.createSocket(host, 443);
/*
* 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/1.1");
out.println("Host: " + host);
out.println("Connection: close");
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();
}
}
}
}
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