I'm writing a FTPClient application, but i keep getting this exception: java.lang.NullPointerException at sun.net.TransferProtocolClient.sendServer(TransferProtocolClient.java:99) at sun.net.ftp.FtpClient.issueCommand(FtpClient.java:160) at sun.net.ftp.FtpClient.openDataConnection(FtpClient.java:218) at sun.net.ftp.FtpClient.get(FtpClient.java:315) at archivetool.FTPClientDialog.getFile(FTPClientDialog.java:579) at archivetool.FTPClientDialog.access$100(FTPClientDialog.java:22) at archivetool.FTPClientDialog$3.run(FTPClientDialog.java:202) the strange thing about this is that the application stops running at line 579, as can be seen above, which is in the middle of a method which performs the same get operation twice. The application performs the operation correctly the first time but not the second time. Here's my code:
Please can someone help me with this
Pete<br />"Reality is an illusion <br />brought on by a lack of <br />drink, drugs and smut"
I didn't go through the code thoroughly, but I have two comments. First, you're referencing an external object, client. It may make sense, but it also means something could be happening outside the method which is effecting it. Second, consider using the Linlyn code, http://www.cs.uwplatt.edu/classes/se273/comm/ftpcomm.html If you use this, be warned, the basic code creates a byte array, and when the array gets filled, it creates a new one, twice the size, and copies thje contents from one to another. In this way, it's very inefficient. If you have any knowledge about the size of the data, you can make it much more efficent with only a few minutes of work. --Mark