code: public static boolean verifyPurchase(String base64PublicKey, String signedData, String signature) {
  		if (TextUtils.isEmpty(signedData) || TextUtils.isEmpty(base64PublicKey) || TextUtils.isEmpty(signature)) {
  			LOGGER.error("Purchase verification failed: missing data.");
  			return false;
  		}
  
  		PublicKey key = Security.generatePublicKey(base64PublicKey);
  		return Security.verify(key, signedData, signature);
  	}
docs: Verifies that the data was signed with the given signature, and returns the verified purchase. The data is in
  JSON format and signed with a private key.
  
  @param base64PublicKey the base64-encoded public key to use for verifying.
  @param signedData the signed JSON string (signed, not encrypted)
  @param signature the signature for the data, signed with the private key
  @return Whether the verification was successful or not