尽管成功连接和登录，Apache FTPSClient仍无法放置文件

Question

我正在使用Apache的FTPS客户端通过FTPS连接文件并将其放置在服务器上。但是它在storeFile方法上失败了。...

 String url = "myTestSTore.com";
 String user = "fake";
 String password = "reallyFake"

FTPSClient ftpClient = new FTPSClient();
ftpClient.connect(url);

ftpClient.enterLocalPassiveMode()

ftpClient.login(user, password);

def reply = ftpClient.getReplyCode();

println "Reply code after logging in is $reply"

FileInputStream fis = new FileInputStream(randomFile)
def reply2 = ftpClient.getReplyCode();

println "Reply Code before attempting file upload is $reply2"

boolean storeFileResult = ftpClient.storeFile(randomFile.getName(), fis)
def reply3 = ftpClient.getReplyCode();

println "Store file  $storeFileResult, reply Code after file upload is $reply3"

输出是...

 06 Aug 2018 11:39:30 - Connecting to ftp server: myTestSTore.com
 Reply code after logging in is 234
 Reply Code before attempting file upload is 230
 Store file result is false , 
       and reply Code after file upload is 522

根据回复代码，看来我们能够连接并登录。但是storeFile方法返回false，之后的回复代码为500。

有什么办法可以说明为什么文件上传失败？

仅返回false并给出500，就无法说明上传失败的原因。