A Problem while Retriving file from FTPS Server
I am working in an application development. On that application i am performing files store, retrieve and delete operations. For identifying the files on server i am using an index(a hash map file) file. every time when i perform upload operation i update "index" file and upload "index" file on server along with other uploading files.
For performing delete operation first i am retrieving the "index" file and based on the index i am deleting the files from server and after updating "index" file i again upload "index" file on server.
I am able to perform file uploading operation successfully but while performing delete operation, i am getting "java.io.EOFException" exception, when i am trying to retrieve "index" file.
i am writing following code to download "index" file from FTPS server
//download index file
if (service.retrFile("INDEX", "") == service.OK) {
try {
ObjectInputStream objIn = new ObjectInputStream(new FileInputStream("INDEX"));
try {
Map<String, FileData> filesUploaded = (HashMap<String, FileData>) objIn.readObject();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
objIn.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
Where "service.ok" returns '0' if it is successfully connected to FTPS server and "FileData" contains information about file(attributes).
Same code i am using while performing uploading operation. there it is working fine with no exception. but while performing delete operation when i am retrieving "index" file i am getting exception on the statement :
Map filesUploaded = (HashMap) objIn.readObject();
Exception is :
SEVERE: null
java.io.EOFException
at java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2298)
at java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:2767)
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:798)
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:298)
at com.pixelvault.gui.DeleteServerFilesDialog.startDeleting(DeleteServerFilesDialog.java:447)
I have checked whether FTPS server connections are properly closed after performing corresponding operations.
I am not getting where i am doing wrong.
please give me your valuable suggestions. i thank to all your suggestions which will help me to overcome with this problem.
i am using org.apache.comm开发者_JS百科ons.net.ftp and "retrFile" is a method created by me for retrieving files from server.
Here is code for "retrFile"
FTPSClient ftp;
public int retrFile(String filename, String savePath) { if (!connected) { return ERR; }
FileOutputStream fout = null;
InputStream bin = null;
try {
ftp.enterLocalPassiveMode();
fout = new FileOutputStream(savePath + filename);
bin = ftp.retrieveFileStream(filename);
if (bin == null) {
fout.close();
return ERR;
}
byte[] b = new byte[ftp.getBufferSize()];
int bytesRead = 0;
while ((bytesRead = bin.read(b, 0, b.length)) != -1) {
fout.write(b, 0, bytesRead);
}
ftp.completePendingCommand();
fout.close();
} catch (FTPConnectionClosedException ex) {
ex.printStackTrace();
connected = false;
return NOT_CONNECTED;
} catch (IOException ex) {
ex.printStackTrace();
return ERR;
} finally {
try {
fout.close();
} catch (IOException ex) {
ex.printStackTrace();
return ERR;
}
try {
if (bin != null) {
bin.close();
}
} catch (IOException ex) {
ex.printStackTrace();
return ERR;
}
}
return OK;
}
Are you sure the INDEX file is correctly downloaded?
It's present in the filesystem when application is closed?
What FTP lib are you using?. i only know commons.net from Apache and i not recognice the "retrFile" file method. Could it be threaded so that the file is not completely downloaded when the readObject statement is executed?
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