Fixes RSA algo and uses .equals for string comparisons (#745)

Author: gguuss

iot/api-client/mqtt_example/src/main/java/com/google/cloud/iot/examples/MqttExample.java

@@ -53,7 +53,7 @@ private static String createJwtRsa(String projectId, String privateKeyFile) thro
 
  byte[] keyBytes = Files.readAllBytes(Paths.get(privateKeyFile));
  PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(keyBytes);
- KeyFactory kf = KeyFactory.getInstance("RSA256");
+ KeyFactory kf = KeyFactory.getInstance("RSA");
 
  return jwtBuilder.signWith(SignatureAlgorithm.RS256, kf.generatePrivate(spec)).compact();
  }
@@ -107,10 +107,11 @@ public static void main(String[] args) throws Exception {
  // to authorize the device.
  connectOptions.setUserName("unused");
 
- if (options.algorithm == "RSA256") {
+ System.out.println(options.algorithm);
+ if (options.algorithm.equals("RS256")) {
  connectOptions.setPassword(
  createJwtRsa(options.projectId, options.privateKeyFile).toCharArray());
- } else if (options.algorithm == "ES256") {
+ } else if (options.algorithm.equals("ES256")) {
  connectOptions.setPassword(
  createJwtEs(options.projectId, options.privateKeyFile).toCharArray());
  } else {