PSI Proton Accelerator Status lite

This non-signed Java Applet (The Java Run-time Environment [JRE] has to be installed on your computer for running this applet.) consisting of 17 classes (total size = 66 kB) (or merged into a single jar file [size = 45 kB] for Java 1.1.x capable browsers) and 3 gif files (total size = 70 kB) allows you to inspect on-line the current official status of the PSI Proton Accelerator Facility. The update rate of the changing data is 1 Hz at the maximum. Because different parts of the applet are running in separate single instance windows the browser's window may be minimized once the applet is started. The applet's main window shows the date and time, the outside temperature, the total used electrical power, the 6 proton beam currents and the operator's messages all transmitted periodically via multicast UDP/IP by the ACS (Accelerator Control System). A program running on an own WWW server (PC9687, OS = Linux) collects these data and writes them into files located in the applet's own "sandbox" from where they are fetched by the applet's running instances via http (Apache server is installed on pc9687).
Three push buttons in the applet's main window allow you to view the gathered data in separate windows in a more detailed form:

Button Action
History The last 1, 12 or 72 hours of the 6 different proton beam currents, the outside temperature and the total electrical power may be seen as a histogram. Refreshing is done automatically with a reasonable frequency.
Messages The collected operator's messages over the last few days are displayed. The text window content is limited to ~7 kB and organized as a FIFO. The Refresh button reloads the (updated) text from the server.
HE info Some statistical data which describe the quality of the 590 MeV proton beam over the last 24 hours are shown. The Refresh button reloads the (updated every 120 sec) table from the server.

This applet has been seen working on the following platforms (OSes) with browsers:

(This platform-independence was achieved by using initially only JDK 1.0.2 features.)
In 2004 the applet has been seen working with all modern browsers on actual OSes.

All Widgets or GUI objects (GUI = Graphic User Interface) are programmed with the AWT ( = Abstract Windowing Toolkit). For each Widget the AWT produces an as similar as possible looking and behaving Peer Object on the host system. Therefore the appearance of buttons, size and position of frames, color palettes, fonts, cursors, scrolling behavior and other things may differ from platform to platform.

If you are using a browser with at least Java 1.1.x capabilities (like Netscape's Navigator 4.5 and higher, Sun's Hotjava 1.1 or Microsoft's Internet Explorer 4.0x and higher for Windows platforms), then it will automatically choose the newer version of this applet, which is based on the Java 1.1 API (more reliable) and down-loadable as a single Java archive (faster).

In order to improve the platform independence, the push buttons of the top and the history frame are user-drawn (and colored).

Urs RohrerGraphic Transport Last updated by Urs Rohrer on 14-Feb-2006