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Java Webdav File Synchronization

I have a cloud storage at strato namely hidrive. It uses the webdav protocol. Note that it's based on HTTP. The client application they provide is poor and buggy so I tried various other tools for synchronization but none just worked the way I need it.
I'm therefore trying to implement it in Java using the Sardine project. Is there any code for hard-copying a local source folder to an external cloud folder? I haven't found anything in that direction.
The following code is supposed to upload the file...
Sardine sardine = SardineFactory.begin("username", "password");
InputStream fis = new FileInputStream(new File("some/file/test.txt"));
sardine.put("https://webdav.hidrive.strato.com/users/username/Backup", fis);
... but throws an exception instead:
Exception in thread "main" com.github.sardine.impl.SardineException: Unexpected response (301 Moved Permanently)
at com.github.sardine.impl.handler.ValidatingResponseHandler.validateResponse(ValidatingResponseHandler.java:48)
at com.github.sardine.impl.handler.VoidResponseHandler.handleResponse(VoidResponseHandler.java:34)
at com.github.sardine.impl.handler.VoidResponseHandler.handleResponse(VoidResponseHandler.java:1)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:218)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:160)
at com.github.sardine.impl.SardineImpl.execute(SardineImpl.java:828)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:755)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:738)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:726)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:696)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:689)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:682)
at com.github.sardine.impl.SardineImpl.put(SardineImpl.java:676)
Printing out the folders in that directory works so the connection/ authentication did succeed:
List<DavResource> resources = sardine.list("https://webdav.hidrive.strato.com/users/username/Backup");
for (DavResource res : resources)
{
System.out.println(res);
}
Please either help me fix my code or link me to some file synchronization library that works for my purpose.

Sardine uses (internally) HttpClient. There is similar question here where you can find an answer Httpclient 4, error 302. How to redirect?.

Try converting the InputStream obj into byte array before you call put(). Something like the below,
byte[] fisByte = IOUtils.toByteArray(fis);
sardine.put("https://webdav.hidrive.strato.com/users/username/Backup", fisByte);
It worked for me. Let me know.

I had to extend the "org.apache.http.impl.client.LaxRedirectStrategy" and also the getRedirect() Method of org.apache.http.impl.client.DefaultRedirectStrategy with a treatment of the needed methods: PUT, MKOL, etc. . By default only GET is redirected.
It looks like this:
private static final String[] REDIRECT_METHODS = new String[] { HttpGet.METHOD_NAME, HttpPost.METHOD_NAME, HttpHead.METHOD_NAME, HttpPut.METHOD_NAME, HttpDelete.METHOD_NAME, HttpMkCol.METHOD_NAME };
isRedirectable-Method
for (final String m : REDIRECT_METHODS) {
if (m.equalsIgnoreCase(method)) {
System.out.println("isRedirectable true");
return true;
}
}
return method.equalsIgnoreCase(HttpPropFind.METHOD_NAME);
getRedirect-Method:
final URI uri = getLocationURI(request, response, context);
final String method = request.getRequestLine().getMethod();
if (method.equalsIgnoreCase(HttpHead.METHOD_NAME)) {
return new HttpHead(uri);
} else if (method.equalsIgnoreCase(HttpGet.METHOD_NAME)) {
return new HttpGet(uri);
} else if (method.equalsIgnoreCase(HttpPut.METHOD_NAME)) {
HttpPut httpPut = new HttpPut(uri);
httpPut.setEntity(((HttpEntityEnclosingRequest) request).getEntity());
return httpPut;
} else if (method.equalsIgnoreCase("MKCOL")) {
return new HttpMkCol(uri);
} else if (method.equalsIgnoreCase("DELETE")) {
return new HttpDelete(uri);
} else {
final int status = response.getStatusLine().getStatusCode();
if (status == HttpStatus.SC_TEMPORARY_REDIRECT) {
return RequestBuilder.copy(request).setUri(uri).build();
} else {
return new HttpGet(uri);
}
}
That worked for me.

HTTP GET to retrieve compressed files

I've developed a HTTP communication object for the purpose pof downloading files via a GET request.
This works just fine when downloading a text file. However, downloading a compressed file such as zip, gz or tar.gz appears to download the file but the file is not valid.
In the case zip I get a meesage saying it tried to move the pointer before the beginnning of the file.
In the case of .tar.gz the message is Data error in file.tar. File is broken.
In all cases the download links I use do allow a complete and correct download from the URL. Yet, the Java code based download brings the file down but it is not valid.
The code is as follows:
public class HTTPCommunicationGet {
private URIBuilder sendData;
private URI target;
private HttpGet getConnection;
public HTTPCommunicationGet(String url, TreeMap<String, String> components) {
super(url, components);
}
public HTTPCommunicationGet(String url, String queryString) {
super(url, queryString);
}
protected void defineSendData() throws URISyntaxException, IOException {
this.sendData = new URIBuilder(new URI(this.getUrl()));
if (this.getComponents() != null && this.getComponents().size() > 0) {
for (Map.Entry<String, String> component : this.getComponents().entrySet()) {
this.sendData.setParameter(component.getKey(), component.getValue());
}
}
}
protected void retrieveRemoteData() throws IOException, MalformedURLException, URISyntaxException, DataMapHTTPGetException {
this.target = this.sendData.build();
this.getConnection = new HttpGet(target);
HttpResponse response = client.execute(this.getConnection);
if (response.getStatusLine().toString().toUpperCase().contains("200 OK")) {
this.setResponse(response.getStatusLine().toString(), "Data Retrieved");
BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
String line = "";
while ((line = rd.readLine()) != null) {
this.remoteData.append(line);
}
} else {
String message = String.format("%s: Provider connection exception; response returned was not 200 OK", this.target.toASCIIString());
this.setResponse(response.getStatusLine().toString(), message);
DataMapHTTPGetException ex = new DataMapHTTPGetException(target.toString(), message);
throw ex;
}
}
public void downloadFiles(String localFile) throws DataMapConnectionException, FileNotFoundException, IOException, URISyntaxException {
// check that we have remoteData set
this.defineSendData();
this.retrieveRemoteData(); // everything is bubbled up to the controller class that is calling this.
File localMetaFile = new File(localFile);
switch (this.archiveMetaFile(localMetaFile)) {
case -1:
IOException ex = new IOException(String.format("The file %s could not be moved", localFile));
throw ex;
//break;
case 0:
infoLog.info(String.format("%s: this file did not already exist", localFile));
break;
case 1:
infoLog.info(String.format("%s: this file was found and successfully archived to the processed directory", localFile));
break;
}
BufferedWriter fileWriter = new BufferedWriter(new FileWriter(localFile));
fileWriter.write(this.remoteData.toString());
fileWriter.close();
}
}
As you can see this is called via downloadFiles after the object has been initialised. I've cut out the code that is not needed for this example such as the archiveMetaFile method.
Any pointers on why this is not working for compressed files is much appreciated.
Cheers
Nathan

The problem is likely that you are using a BufferedReader instead of an InputStream. Readers are used for text data and impose a character encoding whereas InputStreams can handle raw binary data.
Try switching to a BufferedInputStream instead. The use of any Reader class will corrupt binary data.

Apache FTPClient : 530 You aren't logged in

I'm using FTPClient of apache for getting size of specific file from my server. So, the error that I faced in android is 530 You aren't logged in. while my code is such below and I've tested it in pure Java. I don't know why this error occurred on Android but all things are okay in Java.
client.connect("my-server-ip");
client.login("username", "password");
client.setKeepAlive(true);
client.setFileType(FTP.BINARY_FILE_TYPE, FTP.BINARY_FILE_TYPE);
client.setFileTransferMode(FTP.BINARY_FILE_TYPE);
client.sendCommand("SIZE " + "file-path");
try {
sizeStr = client.getReplyString().trim();
this.M_fileData.M_contentLength = Long.parseLong(sizeStr.split(" ")[1]);
System.out.println(sizeStr);
} catch (NumberFormatException e) {
e.printStackTrace();
client.disconnect();
}
Java pure result is : 213 1757682, while android result is 530 You aren't logged in.
Could any one explain me how to solve this ?
Thanks in advance.

- First of all i want you to make sure you have given the android.permission.INTERNET permission.
Well for further reference, i am giving you the code that i used to Download music clip in my android application.
I have used the Apache's commons library
public void goforIt(){
FTPClient con = null;
try
{
con = new FTPClient();
con.connect("50.xx.xx.xx");
if (con.login("Adminxxxxx", "KUjWbk361wobbyl-xxxxxx"))
{
con.enterLocalPassiveMode(); // important!
con.setFileType(FTP.BINARY_FILE_TYPE);
String data = "/sdcard/vivek.m4a";
OutputStream out = new FileOutputStream(new File(data));
boolean result = con.retrieveFile("vivekm4a.m4a", out);
out.close();
if (result) Log.v("download result", "succeeded");
con.logout();
con.disconnect();
}
}
catch (Exception e)
{
Log.v("download result","failed");
e.printStackTrace();
}
}

Whenever 530 error code return it means your username or password is incorrect. And due to login failed you cant upload file.

How can I copy a file on the server using JSch's SCP support?

I managed to create a method which uploads a file into a directory.
How would I have to change this so I could copy a file from /123.html to /en/123.html via JSch?
public void upFile(String source, String fileName, String destination) throws Exception {
try {
try {
// 改变当前路径
client.cd(destination);
} catch (Exception e) {
System.out.println("当前目录不存在，新建目录！");
JschCreateDir.createDir(host, port, username, password, destination);
client.cd(destination);
}
// 上传本地文件 到当前目录
File file = new File(source + fileName);
client.put(new FileInputStream(file), fileName);
} catch (Exception e) {
logout();
throw e;
}
}

I understand your question that you want to copy a file on the server from one directory to another one (and not a local file to the server, which your code already seems to do).
Unfortunately, the SFTP protocol (which is implemented by JSch's ChannelSFTP class) doesn't support copying directly on the server.
You certainly can combine the put and get to copy the file from one location to another, but this will send the contents twice through the wire from server to client and back.
A better way would be to use an exec channel, and simply directly issue the server's system's copy command. On a unixoid server, this would be cp /123.html /en/123.html. (This assumes you have shell access to the server, not an sftp-only access, as I already did see somewhere.)
Here is some code (not tested, you might need to add exception handling):
public void copyFile(Session session, String sourceFile, String destinationFile) {
ChannelExec channel = (ChannelExec) session.openChannel("exec");
channel.setCommand("cp " + sourceFile + " " + destinationFile);
channel.connect();
while(channel.isConnected()) {
Thread.sleep(20);
}
int status = channel.getExitStatus();
if(status != 0)
throw new CopyException("copy failed, exit status is " + status);
}

File upload in Java through FTP

Im trying to develop a simple java code which will upload some contents from local machine to a server/another machine.I used the below code
import sun.net.ftp.*;
import java.io.*;
public class SftpUpload {
public static void main(String args[]) {
String hostname = "some.remote.machine"; //Remote FTP server: Change this
String username = "user"; //Remote user name: Change this
String password = "start123"; //Remote user password: Change this
String upfile = args[0]; //File to upload passed on command line
String remdir = "/home/user"; //Remote directory for file upload
FtpClient ftp = new FtpClient();
try {
ftp.openServer(hostname); //Connect to FTP server
ftp.login(username, password); //Login
ftp.binary(); //Set to binary mode transfer
ftp.cd(remdir); //Change to remote directory
File file = new File(upfile);
OutputStream out = ftp.put(file.getName()); //Start upload
InputStream in = new FileInputStream(file);
byte c[] = new byte[4096];
int read = 0;
while ((read = in.read(c)) != -1 ) {
out.write(c, 0, read);
} //Upload finished
in.close();
out.close();
ftp.closeServer(); //Close connection
} catch (Exception e) {
System.out.println("Error: " + e.getMessage());
}
}
}
But it is showing error in Line 11 as 'Cannot instantiate the type FtpClient'.
Can some one help me how to rectify it.

You cannot instantiate it because sun.net.ftp.FtpClient is abstract class.
I suggest using Apache Commons Net instead of playing with sun.x packages. FTP client example can be found from here.

If you do want to use the Sun classes, use FtpClient.create(), as per the JavaDoc for this class.

i have resolved the exception.thats because my machine is connected in a network which doesnt allow FTP connection.when i tried it in a private dongle it worked.