FTP连接超时421：解析器错误
这个问题已被编辑。 我试图列出FTP目录中的所有文件 – 虽然代码在正常的Netbeans项目中运行时工作正常，但在Maven项目中使用相同的代码时，会导致连接超时421 。 我怎么能摆脱这个？
码：
FTPClient ftpClient = new FTPClient(); ftpClient.connect(host, 21); ftpClient.login(user, pass); ftpClient.enterLocalPassiveMode(); ftpClient.setFileType(FTP.BINARY_FILE_TYPE); FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX); ftpClient.configure(conf); inputStream = FTPUtil.downloadSingleFile(ftpClient, filePath); ftpClient.list(); // It works ftpClient.listNames("/"); // It works ftpClient.changeWorkingDirectory("/"); // It works FTPFile[] files = ftpClient.listFiles("/");// It hangs and stops 421 connection timed out FileZilla日志是： –
(000370)04-04-2013 16:04:32 - (not logged in) (127.0.0.1)> Connected, sending welcome message... (000370)04-04-2013 16:04:32 - (not logged in) (127.0.0.1)> 220 ftp connection started... (000370)04-04-2013 16:04:32 - (not logged in) (127.0.0.1)> USER raja (000370)04-04-2013 16:04:32 - (not logged in) (127.0.0.1)> 331 Password required for raja (000370)04-04-2013 16:04:32 - (not logged in) (127.0.0.1)> PASS **** (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> 230 Logged on (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> TYPE I (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> 200 Type set to I (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> PASV (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> 227 Entering Passive Mode (127,0,0,1,237,187) (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> SYST (000370)04-04-2013 16:04:32 - raja (127.0.0.1)> 215 UNIX emulated by FileZilla (000366)04-04-2013 16:04:33 - raja (127.0.0.1)> 421 Connection timed out.
客户方例外情况如下： – 
当FTP服务器针对SYST命令返回null时，apache-commons 1.4.1中处理解析exception存在严重问题。 我尝试使用3.2版本，问题得到了解决。