KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
keyManagerFactory.init(privateKey, keystorePassword);

TrustManager tm = new X509TrustManager() {
    public void checkClientTrusted(X509Certificate[] chain, String authType)
            throws CertificateException {
    }

    public void checkServerTrusted(X509Certificate[] chain, String authType)
            throws CertificateException {
        if (chain == null || chain.length != 1)
            throw new CertificateException("Chain Length Not Correct");

        X509Certificate partnerCert = chain[0];

        try {
            java.security.cert.Certificate storedCert = trustedKeys.getCertificate(partnerAlias);

            if (storedCert == null || !storedCert.equals(partnerCert)) {
                if (prompt(...)) {
                    addTrustedCertificate(partnerCert);
                }
                else {
                    throw new CertificateException("Certificate rejected");
                }
            }
        } catch (KeyStoreException e) {
            e.printStackTrace();
            throw new CertificateException("KeystoreException");
        } catch (NoSuchAlgorithmException|IOException e) {
            e.printStackTrace();
            throw new CertificateException("Internal error");
        }
    }

    public X509Certificate[] getAcceptedIssuers() {
        return new X509Certificate[] {};
    }
};

sslContext = SSLContext.getInstance("TLSv1.2");
sslContext.init(keyManagerFactory.getKeyManagers(), new TrustManager[] {tm}, null);
...
SSLSocket socket = sslContext.getSocketFactory().createSocket(...);
socket.setSoTimeout(60*1000);

Exception in thread "main" java.io.IOException: Stream closed
    at java.io.BufferedInputStream.getBufIfOpen(BufferedInputStream.java:162)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:325)
    at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:283)
    at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:325)
    at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:177)
    at java.io.InputStreamReader.read(InputStreamReader.java:184)
    at java.io.BufferedReader.fill(BufferedReader.java:154)
    at java.io.BufferedReader.readLine(BufferedReader.java:317)
    at java.io.BufferedReader.readLine(BufferedReader.java:382)
    at Client.main(Client.java:33)