Show certificate presented on port

openssl s_client -connect HOST:PORTNUMBER

In order to check if java correctly handles certs presented by web services, SSLPoke can be used.
Add the following code to a file called SSLPoke.java

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

/** Establish a SSL connection to a host and port, writes a byte and
 * prints the response. See
 * http://confluence.atlassian.com/display/JIRA/Connecting+to+SSL+services
 */
public class SSLPoke {
    public static void main(String[] args) {
                if (args.length != 2) {
                        System.out.println("Usage: "+SSLPoke.class.getName()+" <host> <port>");
                        System.exit(1);
                }
                try {
                        SSLSocketFactory sslsocketfactory = (SSLSocketFactory) SSLSocketFactory.getDefault();
                        SSLSocket sslsocket = (SSLSocket) sslsocketfactory.createSocket(args[0], Integer.parseInt(args[1]));

                        InputStream in = sslsocket.getInputStream();
                        OutputStream out = sslsocket.getOutputStream();

                        // Write a test byte to get a reaction :)
                        out.write(1);

                        while (in.available() > 0) {
                                System.out.print(in.read());
                        }
                        System.out.println("Successfully connected");

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

Then run the following;

javac SSLPoke.java
java SSLPoke <hostname> <port>