Synnefo » Pithos Web Client

/*

 * Copyright 2011 GRNET S.A. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or

 * without modification, are permitted provided that the following

 * conditions are met:

 *

 *   1. Redistributions of source code must retain the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer.

 *

 *   2. Redistributions in binary form must reproduce the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer in the documentation and/or other materials

 *      provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * The views and conclusions contained in the software and

 * documentation are those of the authors and should not be

 * interpreted as representing official policies, either expressed

 * or implied, of GRNET S.A.

 */

package gr.grnet.pithos.web.client;

import com.google.gwt.core.client.Scheduler;

import com.google.gwt.core.client.Scheduler.ScheduledCommand;

import com.google.gwt.http.client.Request;

import com.google.gwt.http.client.RequestBuilder;

import com.google.gwt.http.client.RequestCallback;

import com.google.gwt.http.client.RequestException;

import com.google.gwt.http.client.Response;

import com.google.gwt.json.client.JSONArray;

import com.google.gwt.json.client.JSONObject;

import com.google.gwt.json.client.JSONParser;

import com.google.gwt.json.client.JSONString;

import com.google.gwt.json.client.JSONValue;

import com.google.gwt.user.client.Command;

import com.google.gwt.view.client.SelectionChangeEvent;

import com.google.gwt.view.client.SelectionChangeEvent.Handler;

import com.google.gwt.view.client.SingleSelectionModel;

import gr.grnet.pithos.web.client.foldertree.AccountResource;

import gr.grnet.pithos.web.client.foldertree.File;

import gr.grnet.pithos.web.client.foldertree.Folder;

import gr.grnet.pithos.web.client.foldertree.FolderTreeView;

import gr.grnet.pithos.web.client.foldertree.FolderTreeViewModel;

import gr.grnet.pithos.web.client.foldertree.Resource;

import gr.grnet.pithos.web.client.rest.DeleteRequest;

import gr.grnet.pithos.web.client.rest.GetRequest;

import gr.grnet.pithos.web.client.rest.PutRequest;

import gr.grnet.pithos.web.client.rest.RestException;

import gr.grnet.pithos.web.client.tagtree.Tag;

import gr.grnet.pithos.web.client.tagtree.TagTreeView;

import gr.grnet.pithos.web.client.tagtree.TagTreeViewModel;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Date;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import com.google.gwt.core.client.EntryPoint;

import com.google.gwt.core.client.GWT;

import com.google.gwt.event.logical.shared.ResizeEvent;

import com.google.gwt.event.logical.shared.ResizeHandler;

import com.google.gwt.event.logical.shared.SelectionEvent;

import com.google.gwt.event.logical.shared.SelectionHandler;

import com.google.gwt.i18n.client.DateTimeFormat;

import com.google.gwt.resources.client.ClientBundle;

import com.google.gwt.resources.client.ImageResource;

import com.google.gwt.user.client.Cookies;

import com.google.gwt.user.client.Event;

import com.google.gwt.user.client.History;

import com.google.gwt.user.client.Window;

import com.google.gwt.user.client.ui.AbstractImagePrototype;

import com.google.gwt.user.client.ui.DecoratedTabPanel;

import com.google.gwt.user.client.ui.HasHorizontalAlignment;

import com.google.gwt.user.client.ui.HorizontalSplitPanel;

import com.google.gwt.user.client.ui.RootPanel;

import com.google.gwt.user.client.ui.TabPanel;

import com.google.gwt.user.client.ui.VerticalPanel;

import java.util.Set;

/**

 * Entry point classes define <code>onModuleLoad()</code>.

 */

public class Pithos implements EntryPoint, ResizeHandler {

        /**

         * A constant that denotes the completion of an IncrementalCommand.

         */

        public static final boolean DONE = false;

        public static final int VISIBLE_FILE_COUNT = 25;

        /**

         * Instantiate an application-level image bundle. This object will provide

         * programmatic access to all the images needed by widgets.

         */

        private static Images images = (Images) GWT.create(Images.class);

    public String getUsername() {

        return username;

    }

    public void setAccount(AccountResource acct) {

        account = acct;

    }

    public AccountResource getAccount() {

        return account;

    }

    public void updateFolder(Folder f, boolean showfiles) {

        folderTreeView.updateFolder(f, showfiles);

    }

    public void updateTag(Tag t) {

        tagTreeView.updateTag(t);

    }

    public void updateTags() {

        tagTreeViewModel.initialize(getAllTags());

    }

    public List<Tag> getAllTags() {

        List<Tag> tagList = new ArrayList<Tag>();

        for (Folder f : account.getContainers()) {

            for (String t : f.getTags()) {

                tagList.add(new Tag(t));

            }

        }

        return tagList;

    }

    /**

         * An aggregate image bundle that pulls together all the images for this

         * application into a single bundle.

         */

        public interface Images extends ClientBundle, TopPanel.Images, FilePropertiesDialog.Images, MessagePanel.Images, FileList.Images {

                @Source("gr/grnet/pithos/resources/document.png")

                ImageResource folders();

                @Source("gr/grnet/pithos/resources/edit_group_22.png")

                ImageResource groups();

                @Source("gr/grnet/pithos/resources/search.png")

                ImageResource search();

        }

        /**

         * The Application Clipboard implementation;

         */

        private Clipboard clipboard = new Clipboard();

        /**

         * The top panel that contains the menu bar.

         */

        private TopPanel topPanel;

        /**

         * The panel that contains the various system messages.

         */

        private MessagePanel messagePanel = new MessagePanel(Pithos.images);

        /**

         * The bottom panel that contains the status bar.

         */

        private StatusPanel statusPanel = null;

        /**

         * The file list widget.

         */

        private FileList fileList;

        /**

         * The tab panel that occupies the right side of the screen.

         */

        private TabPanel inner = new DecoratedTabPanel(){

//                public void onBrowserEvent(com.google.gwt.user.client.Event event) {

//                        if (DOM.eventGetType(event) == Event.ONCONTEXTMENU){

//                                if(isFileListShowing()){

//                                        getFileList().showContextMenu(event);

//                                }

//                        }

//                };

        };

        /**

         * The split panel that will contain the left and right panels.

         */

        private HorizontalSplitPanel splitPanel = new HorizontalSplitPanel();

        /**

         * The currently selected item in the application, for use by the Edit menu

         * commands. Potential types are Folder, File, User and Group.

         */

        private Object currentSelection;

        /**

         * The WebDAV password of the current user

         */

        private String webDAVPassword;

        public HashMap<String, String> userFullNameMap = new HashMap<String, String>();

    private String username = null;

    /**

     * The authentication token of the current user.

     */

    private String token;

    private SingleSelectionModel<Folder> folderTreeSelectionModel;

    private FolderTreeViewModel folderTreeViewModel;

    private FolderTreeView folderTreeView;

    private SingleSelectionModel<Tag> tagTreeSelectionModel;

    private TagTreeViewModel tagTreeViewModel;

    private TagTreeView tagTreeView;

    private AccountResource account;

        @Override

        public void onModuleLoad() {

                if (parseUserCredentials())

            initialize();

        }

    private void initialize() {

        topPanel = new TopPanel(this, Pithos.images);

        topPanel.setWidth("100%");

        messagePanel.setWidth("100%");

        messagePanel.setVisible(false);

        // Inner contains the various lists.

        inner.sinkEvents(Event.ONCONTEXTMENU);

        inner.setAnimationEnabled(true);

        inner.getTabBar().addStyleName("pithos-MainTabBar");

        inner.getDeckPanel().addStyleName("pithos-MainTabPanelBottom");

        inner.setWidth("100%");

        inner.addSelectionHandler(new SelectionHandler<Integer>() {

            @Override

            public void onSelection(SelectionEvent<Integer> event) {

                int tabIndex = event.getSelectedItem();

                switch (tabIndex) {

                    case 0:

                        break;

                }

            }

        });

        folderTreeSelectionModel = new SingleSelectionModel<Folder>();

        folderTreeSelectionModel.addSelectionChangeHandler(new SelectionChangeEvent.Handler() {

            @Override

            public void onSelectionChange(SelectionChangeEvent event) {

                if (folderTreeSelectionModel.getSelectedObject() != null) {

                    tagTreeSelectionModel.setSelected(tagTreeSelectionModel.getSelectedObject(), false);

                    Folder f = folderTreeSelectionModel.getSelectedObject();

                    updateFolder(f, true);

                }

            }

        });

        folderTreeViewModel = new FolderTreeViewModel(this, folderTreeSelectionModel);

        folderTreeView = new FolderTreeView(folderTreeViewModel);

        fileList = new FileList(this, images, folderTreeView);

        inner.add(fileList, createHeaderHTML(AbstractImagePrototype.create(images.folders()), "Files"), true);

        tagTreeSelectionModel = new SingleSelectionModel<Tag>();

        tagTreeSelectionModel.addSelectionChangeHandler(new Handler() {

            @Override

            public void onSelectionChange(SelectionChangeEvent event) {

                if (tagTreeSelectionModel.getSelectedObject() != null) {

                    folderTreeSelectionModel.setSelected(folderTreeSelectionModel.getSelectedObject(), false);

                    Tag t = tagTreeSelectionModel.getSelectedObject();

                    updateTag(t);

                }

            }

        });

        tagTreeViewModel = new TagTreeViewModel(this, tagTreeSelectionModel);

        tagTreeView = new TagTreeView(tagTreeViewModel);

        VerticalPanel trees = new VerticalPanel();

        trees.add(folderTreeView);

        trees.add(tagTreeView);

        // Add the left and right panels to the split panel.

        splitPanel.setLeftWidget(trees);

        splitPanel.setRightWidget(inner);

        splitPanel.setSplitPosition("25%");

        splitPanel.setSize("100%", "100%");

        splitPanel.addStyleName("pithos-splitPanel");

        // Create a dock panel that will contain the menu bar at the top,

        // the shortcuts to the left, the status bar at the bottom and the

        // right panel taking the rest.

        VerticalPanel outer = new VerticalPanel();

        outer.add(topPanel);

        outer.add(messagePanel);

        outer.add(splitPanel);

        statusPanel = new StatusPanel();

        outer.add(statusPanel);

        outer.setWidth("100%");

        outer.setCellHorizontalAlignment(messagePanel, HasHorizontalAlignment.ALIGN_CENTER);

        // Hook the window resize event, so that we can adjust the UI.

        Window.addResizeHandler(this);

        // Clear out the window's built-in margin, because we want to take

        // advantage of the entire client area.

        Window.setMargin("0px");

        // Finally, add the outer panel to the RootPanel, so that it will be

        // displayed.

        RootPanel.get().add(outer);

        // Call the window resized handler to get the initial sizes setup. Doing

        // this in a deferred command causes it to occur after all widgets'

        // sizes have been computed by the browser.

        Scheduler.get().scheduleDeferred(new ScheduledCommand() {

            @Override

            public void execute() {

                onWindowResized(Window.getClientHeight());

            }

        });

        Scheduler.get().scheduleDeferred(new ScheduledCommand() {

            @Override

            public void execute() {

                fetchAccount();

            }

        });

    }

    public void showFiles(Folder f) {

        inner.selectTab(0);

        if (f.isTrash()) {

            fileList.showTrash();

        }

        else

            fileList.showFiles();

        Set<File> files = f.getFiles();

        showFiles(files);

    }

    public void showFiles(Set<File> files) {

        //Iterator<File> iter = files.iterator();

        //fetchFile(iter, files);

        fileList.setFiles(new ArrayList<File>(files));

    }

    private void fetchFile(final Iterator<File> iter, final Set<File> files) {

        if (iter.hasNext()) {

            File file = iter.next();

            String path = file.getUri() + "?format=json";

            GetRequest<File> getFile = new GetRequest<File>(File.class, getApiPath(), username, path, file) {

                @Override

                public void onSuccess(File result) {

                    fetchFile(iter, files);

                }

                @Override

                public void onError(Throwable t) {

                    GWT.log("Error getting file", t);

                    if (t instanceof RestException)

                        displayError("Error getting file: " + ((RestException) t).getHttpStatusText());

                    else

                        displayError("System error fetching file: " + t.getMessage());

                }

            };

            getFile.setHeader("X-Auth-Token", "0000");

            Scheduler.get().scheduleDeferred(getFile);

        }

        else

            fileList.setFiles(new ArrayList<File>(files));

    }

    /**

         * Parse and store the user credentials to the appropriate fields.

         */

        private boolean parseUserCredentials() {

        username = Window.Location.getParameter("user");

        token = Window.Location.getParameter("token");

        Configuration conf = (Configuration) GWT.create(Configuration.class);

        if (username == null || username.length() == 0 || token == null || token.length() == 0) {

            String cookie = conf.authCookie();

            String auth = Cookies.getCookie(cookie);

            if (auth == null) {

                authenticateUser();

                return false;

            }

            else {

                String[] authSplit = auth.split("\\" + conf.cookieSeparator(), 2);

                if (authSplit.length != 2) {

                    authenticateUser();

                    return false;

                }

                else {

                    username = authSplit[0];

                    token = authSplit[1];

                    return true;

                }

            }

        }

        else {

            Cookies.setCookie(conf.authCookie(), username + conf.cookieSeparator() + token);

            return true;

        }

    }

    /**

         * Redirect the user to the login page for authentication.

         */

        protected void authenticateUser() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

        Window.Location.assign(Window.Location.getHost() + conf.loginUrl() + "?next=" + Window.Location.getHref());

        }

    private void fetchAccount() {

        String path = "?format=json";

        GetRequest<AccountResource> getAccount = new GetRequest<AccountResource>(AccountResource.class, getApiPath(), username, path) {

            @Override

            public void onSuccess(AccountResource result) {

                account = result;

                inner.selectTab(0);

                if (account.getContainers().isEmpty())

                    createHomeContainers();

                else

                    folderTreeViewModel.initialize(account);

            }

            @Override

            public void onError(Throwable t) {

                GWT.log("Error getting account", t);

                if (t instanceof RestException)

                    displayError("Error getting account: " + ((RestException) t).getHttpStatusText());

                else

                    displayError("System error fetching user data: " + t.getMessage());

            }

        };

        getAccount.setHeader("X-Auth-Token", token);

        Scheduler.get().scheduleDeferred(getAccount);

    }

    private void createHomeContainers() {

        String path = "/pithos";

        PutRequest createPithos = new PutRequest(getApiPath(), getUsername(), path) {

            @Override

            public void onSuccess(Resource result) {

                fetchAccount();

            }

            @Override

            public void onError(Throwable t) {

                GWT.log("Error creating pithos", t);

                if (t instanceof RestException)

                    displayError("Error creating pithos: " + ((RestException) t).getHttpStatusText());

                else

                    displayError("System error Error creating pithos: " + t.getMessage());

            }

        };

        createPithos.setHeader("X-Auth-Token", getToken());

        Scheduler.get().scheduleDeferred(createPithos);

    }

        /**

         * Creates an HTML fragment that places an image & caption together, for use

         * in a group header.

         *

         * @param imageProto an image prototype for an image

         * @param caption the group caption

         * @return the header HTML fragment

         */

        private String createHeaderHTML(AbstractImagePrototype imageProto, String caption) {

                String captionHTML = "<table class='caption' cellpadding='0' " 

                + "cellspacing='0'>" + "<tr><td class='lcaption'>" + imageProto.getHTML() 

                + "</td><td id =" + caption +" class='rcaption'><b style='white-space:nowrap'>&nbsp;" 

                + caption + "</b></td></tr></table>";

                return captionHTML;

        }

        private void onWindowResized(int height) {

                // Adjust the split panel to take up the available room in the window.

                int newHeight = height - splitPanel.getAbsoluteTop() - 60;

                if (newHeight < 1)

                        newHeight = 1;

                splitPanel.setHeight("" + newHeight);

                inner.setHeight("" + newHeight);

        }

        @Override

        public void onResize(ResizeEvent event) {

                int height = event.getHeight();

                onWindowResized(height);

        }

        /**

         * Display an error message.

         *

         * @param msg the message to display

         */

        public void displayError(String msg) {

                messagePanel.displayError(msg);

        }

        /**

         * Display a warning message.

         *

         * @param msg the message to display

         */

        public void displayWarning(String msg) {

                messagePanel.displayWarning(msg);

        }

        /**

         * Display an informational message.

         *

         * @param msg the message to display

         */

        public void displayInformation(String msg) {

                messagePanel.displayInformation(msg);

        }

        /**

         * Retrieve the fileList.

         *

         * @return the fileList

         */

        public FileList getFileList() {

                return fileList;

        }

        /**

         * Retrieve the topPanel.

         *

         * @return the topPanel

         */

        TopPanel getTopPanel() {

                return topPanel;

        }

        /**

         * Retrieve the clipboard.

         *

         * @return the clipboard

         */

        public Clipboard getClipboard() {

                return clipboard;

        }

        public StatusPanel getStatusPanel() {

                return statusPanel;

        }

        public String getToken() {

                return token;

        }

        public String getWebDAVPassword() {

                return webDAVPassword;

        }

        public static native void preventIESelection() /*-{

                $doc.body.onselectstart = function () { return false; };

        }-*/;

        public static native void enableIESelection() /*-{

                if ($doc.body.onselectstart != null)

                $doc.body.onselectstart = null;

        }-*/;

        /**

         * @return the absolute path of the API root URL

         */

        public String getApiPath() {

                Configuration conf = (Configuration) GWT.create(Configuration.class);

                return conf.apiPath();

        }

        /**

         * History support for folder navigation

         * adds a new browser history entry

         *

         * @param key

         */

        public void updateHistory(String key){

//                Replace any whitespace of the initial string to "+"

//                String result = key.replaceAll("\\s","+");

//                Add a new browser history entry.

//                History.newItem(result);

                History.newItem(key);

        }

    public void deleteFolder(final Folder folder) {

        String path = getApiPath() + getUsername() + "/" + folder.getContainer() + "?format=json&delimiter=/&prefix=" + folder.getPrefix();

        RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, path);

        builder.setHeader("If-Modified-Since", "0");

        builder.setHeader("X-Auth-Token", getToken());

        try {

            builder.sendRequest("", new RequestCallback() {

                @Override

                public void onResponseReceived(Request request, Response response) {

                    if (response.getStatusCode() == Response.SC_OK) {

                        JSONValue json = JSONParser.parseStrict(response.getText());

                        JSONArray array = json.isArray();

                        int i = 0;

                        if (array != null) {

                            deleteObject(folder, i, array);

                        }

                    }

                }

                @Override

                public void onError(Request request, Throwable exception) {

                    displayError("System error unable to delete folder: " + exception.getMessage());

                }

            });

        }

        catch (RequestException e) {

        }

    }

    public void deleteObject(final Folder folder, final int i, final JSONArray array) {

        if (i < array.size()) {

            JSONObject o = array.get(i).isObject();

            if (o != null && !o.containsKey("subdir")) {

                JSONString name = o.get("name").isString();

                String path = "/" + folder.getContainer() + "/" + name.stringValue();

                DeleteRequest delete = new DeleteRequest(getApiPath(), getUsername(), path) {

                    @Override

                    public void onSuccess(Resource result) {

                        deleteObject(folder, i + 1, array);

                    }

                    @Override

                    public void onError(Throwable t) {

                        GWT.log("", t);

                        displayError("System error unable to delete folder: " + t.getMessage());

                    }

                };

                delete.setHeader("X-Auth-Token", getToken());

                Scheduler.get().scheduleDeferred(delete);

            }

            else {

                String subdir = o.get("subdir").isString().stringValue();

                subdir = subdir.substring(0, subdir.length() - 1);

                String path = getApiPath() + getUsername() + "/" + folder.getContainer() + "?format=json&delimiter=/&prefix=" + subdir;

                RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, path);

                builder.setHeader("If-Modified-Since", "0");

                builder.setHeader("X-Auth-Token", getToken());

                try {

                    builder.sendRequest("", new RequestCallback() {

                        @Override

                        public void onResponseReceived(Request request, Response response) {

                            if (response.getStatusCode() == Response.SC_OK) {

                                JSONValue json = JSONParser.parseStrict(response.getText());

                                JSONArray array2 = json.isArray();

                                if (array2 != null) {

                                    int l = array.size();

                                    for (int j=0; j<array2.size(); j++) {

                                        array.set(l++, array2.get(j));

                                    }

                                }

                                deleteObject(folder, i + 1, array);

                            }

                        }

                        @Override

                        public void onError(Request request, Throwable exception) {

                            displayError("System error unable to delete folder: " + exception.getMessage());

                        }

                    });

                }

                catch (RequestException e) {

                }

            }

        }

        else {

            String path = folder.getUri();

            DeleteRequest deleteFolder = new DeleteRequest(getApiPath(), getUsername(), path) {

                @Override

                public void onSuccess(Resource result) {

                    updateFolder(folder.getParent(), true);

                }

                @Override

                public void onError(Throwable t) {

                    GWT.log("", t);

                    if (t instanceof RestException) {

                        displayError("Unable to delete folder: "+((RestException) t).getHttpStatusText());

                    }

                    else

                        displayError("System error unable to delete folder: " + t.getMessage());

                }

            };

            deleteFolder.setHeader("X-Auth-Token", getToken());

            Scheduler.get().scheduleDeferred(deleteFolder);

        }

    }

    public FolderTreeView getFolderTreeView() {

        return folderTreeView;

    }

    public void copyFiles(final Iterator<File> iter, final String targetUri, final Command callback) {

        if (iter.hasNext()) {

            File file = iter.next();

            String path = targetUri + "/" + file.getName();

            PutRequest copyFile = new PutRequest(getApiPath(), getUsername(), path) {

                @Override

                public void onSuccess(Resource result) {

                    copyFiles(iter, targetUri, callback);

                }

                @Override

                public void onError(Throwable t) {

                    GWT.log("", t);

                    if (t instanceof RestException) {

                        displayError("Unable to copy file: " + ((RestException) t).getHttpStatusText());

                    }

                    else

                        displayError("System error unable to copy file: "+t.getMessage());

                }

            };

            copyFile.setHeader("X-Auth-Token", getToken());

            copyFile.setHeader("X-Copy-From", file.getUri());

            Scheduler.get().scheduleDeferred(copyFile);

        }

        else  if (callback != null) {

            callback.execute();

        }

    }

    public void copySubfolders(final Iterator<Folder> iter, final String targetUri, final Command callback) {

        if (iter.hasNext()) {

            final Folder f = iter.next();

            copyFolder(f, targetUri, callback);

        }

        else  if (callback != null) {

            callback.execute();

        }

    }

    public void copyFolder(final Folder f, final String targetUri, final Command callback) {

        String path = targetUri + "/" + f.getName();

        PutRequest createFolder = new PutRequest(getApiPath(), getUsername(), path) {

            @Override

            public void onSuccess(Resource result) {

                Iterator<File> iter = f.getFiles().iterator();

                copyFiles(iter, targetUri + "/" + f.getName(), new Command() {

                    @Override

                    public void execute() {

                        Iterator<Folder> iterf = f.getSubfolders().iterator();

                        copySubfolders(iterf, targetUri + "/" + f.getName(), new Command() {

                            @Override

                            public void execute() {

                                callback.execute();

                            }

                        });

                    }

                });

            }

            @Override

            public void onError(Throwable t) {

                GWT.log("", t);

                if (t instanceof RestException) {

                    displayError("Unable to create folder:" + ((RestException) t).getHttpStatusText());

                }

                else

                    displayError("System error creating folder:" + t.getMessage());

            }

        };

        createFolder.setHeader("X-Auth-Token", getToken());

        createFolder.setHeader("Accept", "*/*");

        createFolder.setHeader("Content-Length", "0");

        createFolder.setHeader("Content-Type", "application/folder");

        Scheduler.get().scheduleDeferred(createFolder);

    }

}