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Secure file transfer with Java and Versile

Just made an example of how to transfer a file over a secure and authenticated connection in pure Java - without having to use additional technology like ssh/scp. Versile has all you need for creating a secure and authenticated connection, and you'll decide what files you want to expose - nothing more - nothing less. This is the file server (include versile.jar in your classpath - and create a file called "personregister.txt" in the working directory): package versileexample; import java.io.File; import java.io.FileNotFoundException; import java.io.RandomAccessFile; import java.security.interfaces.RSAPublicKey; import java.util.logging.Level; import java.util.logging.Logger; import org.versile.Versile; import org.versile.common.auth.VAuth; import org.versile.common.auth.VCredentials; import org.versile.common.auth.VPrivateCredentials; import org.versile.common.peer.VInetSocketPeer; import org.versile.common.peer.VPeer; import o

Converting from linear to logarithmic scale

A simple function useful to plot a logarithmic scale. Just provide it with the min and max values of the scale and the value you want to convert - and you'll get in return a value as it should be positioned on a logarithmic scale in the given range. public double toLogScale(double min, double max,double val) { double logmin = Math.log(min); double logmax = Math.log(max); double logscale = (Math.log(val)-logmin) / (logmax-logmin); return min+(max-min)*logscale; }

Ubuntu desktop in the cloud accessible with VNC

To create a Ubuntu desktop on Amazon EC2 that can be accessed by VNC I did the following steps: 1. Create 64-bit Ubuntu server instance 2. Install ubuntu desktop: sudo apt-get install ubuntu-desktop 3. Install x11vnc sudo apt-get install x11vnc 4. Install xvfb sudo apt-get install xvfb 5. Configure x11vnc sudo nano /etc/init/x11vnc.conf start on login-session-start script /usr/bin/x11vnc -xkb -auth /var/run/lightdm/root/:0 -noxrecord -noxfixes -noxdamage -rfbauth /etc/x11vnc.pass -forever -bg -rfbport 5900 -o /var/log/x11vnc.log end script And you should also set a password for your vnc sessions: sudo x11vnc -storepasswd /etc/x11vnc.pass 6. Configure X server to use xvfb: (Add the xserver-command line) sudo nano /etc/lightdm/lightdm.conf [SeatDefaults] greeter-session=unity-greeter user-session=ubuntu xserver-command=/etc/X11/xinit/xserverrc (Replace the exec line) sudo nano /etc/X11/xinit/xserverrc #!/bin/sh #exec /us

Exporting Kendo UI GRID to Excel with Java

This is a simple method of creating an Excel export function on your Kendo UI grid with a Java EE server. JS function to trigger Excel export In your web-page with the grid - insert this JS function. You should create a button or similar that calls this when you want to perform the export from the UI. function exportGridToExcel() { var grid = $("#grid").data("kendoGrid"); var currentPage = grid.dataSource.page(); var allPages = new Array(); for(var n=1;n<=grid.dataSource.totalPages();n++) { grid.dataSource.page(n); var view = grid.dataSource.view(); for(var x=0;x<view.length;x++) { allPages.push(view[x]); } } $("#excelExportGridData").val(JSON.stringify({"rows": allPages, "cols": grid.columns})); $("#exportToExcelForm").submit(); grid.dataSource.page(currentPage); } Hidden form and iframe You also nee