SparkPost send mail exception

Question

Sparkpost send mail - 私はスパークポストのjarファイルを入れてスパークポスト開発者が提供したものと同じですが、メールを送信することはできません。

final String API_KEY = "xxxx"; 
    sparky.sendMessage("xyz@abc.com", // from email 
    "xxx@gmail.com",     // to email 
    "The subject of the message",  // subject of email 
    "The text part of the email",  // text of email body 
    "<b>The HTML part of the email</b>"); // Html text of email body 


But getting this exception 

    com.sparkpost.exception.SparkPostErrorServerResponseException: Unexpected server response ContentType(null) from https://api.sparkpost.com/api/v1/URI [scheme=null, userInfo=null, host=null, port=-1, path=transmissions, queryParams=[num_rcpt_errors=0], fragment=null] contentLength(0) 
     at com.sparkpost.transport.RestConnection.receiveErrorResponse(RestConnection.java:326) 
     at com.sparkpost.transport.RestConnection.receiveResponse(RestConnection.java:235) 
     at com.sparkpost.transport.RestConnection.doHttpMethod(RestConnection.java:390) 
     at com.sparkpost.transport.RestConnection.post(RestConnection.java:433) 
     at com.sparkpost.resources.ResourceTransmissions.createTransmission(ResourceTransmissions.java:40) 
     at com.sparkpost.resources.ResourceTransmissions.create(ResourceTransmissions.java:27) 
     at com.sparkpost.Client.sendMessage(Client.java:115) 
     at com.sparkpost.Client.sendMessage(Client.java:90) 
     at mail.SendMail$1.run(SendMail.java:60) 
     at java.lang.Thread.run(Thread.java:745) 

Answer 1

jarを使用することを奨励するmavenまたはgradle依存関係で1回試してください。私がjcenterリポジトリからgradleを使うと、私は解決されます。