gistfile1.txt

//First create the httpClient in Dropwizard's run method as documented        
final HttpClient httpClient = new HttpClientBuilder().using(configuration.getHttpClient()).build();

try {
  //Create KeyStore obejcts for both the keystore and truststore
  KeyStore keystore = KeyStore.getInstance(KeyStore.getDefaultType());
  KeyStore truststore = KeyStore.getInstance(KeyStore.getDefaultType());
  
  //Then load the actual keystore/truststore file(s), they are the same file in my case
  keystore.load(new FileInputStream(configuration.getKeyStore()), configuration.getKeyStorePassword().toCharArray());
  truststore.load(new FileInputStream(configuration.getKeyStore()), configuration.getKeyStorePassword().toCharArray());
  
  //Then register a Scheme for HTTPS, in the httpClient, using your loaded keystore, keyPassword, and truststore
  //The keypassword, second argument, is the password of your key, not the keystore.
  httpClient.getConnectionManager().getSchemeRegistry().register(new Scheme("https", 443, 
      new SSLSocketFactory(keystore, configuration.getKeyStorePassword(), truststore)));
} catch (Throwable t) {
  //If something goes wrong, just kill Dropwizard with a RuntimeException
  throw new RuntimeException("Couldn't register the HTTPS scheme in HttpClient", t);
}