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Once a while is needed java executable jar file using java jar tool. Here is an example of the batch file, let’s say makejar.bat, which can create executable jar file. Expects package name examples.
The first parameter is package subdirectory, second parameter is class with public static main method.

@echo off
if "%1" == ""  goto help
if "%2" == ""  goto help

set makeSubdir=%1
set makeMainClass=%2

echo Manifest-Version: 1.0  > myManifest
echo Created-By: Joe Doe >> myManifest
echo Main-Class: %makeMainClass% >> myManifest
rem Class-Path: lib/lib1.jar lib/lib2.jar lib/lib3.jar

jar cvfm %makeSubdir%.jar myManifest   examples/%makeSubdir%
goto end

:help
echo Usage:
echo %0 subdirectory Main-Class
echo Example"
echo %0 jlist examples.jlist.List
echo .
echo Creates jlist.jar
echo Call:
echo java -jar jlist.jar

:end

Once a while is handy to be able use Skype from somebody else computer. In this case one can copy Skype and personal data (contact list) to USB flash drive. Here is what could be done. This example is using Windows 7.

md F:\Skype\data
copy C:\Program Files (x86)\Skype\Phone\Skype.exe F:\Skype
xcopy  %USERPROFILE%\AppData\Roaming\Skype\yourSkypeName  F:\Skype\data\yourSkypeName\ /s

Now is possible to invoke Skype, for example from F:\Skype like this:

start "Skype" Skype /datapath:data /removable

Skype version (32 bit version) 6.3.0.105 has size 18,642,024 B, user data can be like 4 MB.

Answer can be found at TED speech by Terry Moore, executive director at the Radius Foundation.

When Arabic texts made their way to Spain in the 11th century, Europe wanted to translate this mathematical wisdom of the East into a written, Western language. Attempts to do so, however, proved to be problematic. As it turned out, Arabic sounds do not translate well into European patterns of speech, nor are there ample characters to represent these sounds. An Arabic word meaning “the unknown thing,” a word used throughout early mathematical proofs, contained the Arabic letter “sheen.” The problem was, Moore explains, there was no “sh” sound in the Spanish language. So, the language crafters borrowed the “ka” sound from the Greek letter χ or “chi.” Later, chi was replaced with the Latin X. And once the material was translated into Latin, it formed material for math textbooks that we continue to read today.

So why is the letter “x” the unknown?
Because you can’t say “sh” in Spanish!

For taking picture of the sky is mount of the camera maybe more important, than camera itself. For long exposure, for sure. Cheap and portable solution could be hinge mount or hing tracker. Several of such mounts are at Gary Seronik website.  Other name is scotch mount [2] or barn door [2] tracker. One can actually rotate by hand with reasonably good results. Interesting is also auroracam.

Nice applet showing Solar system at  http://weelookang.blogspot.com/2011/06/ejs-open-source-kepler-3rd-law-system.html   There are links to more interesting applet of virtual astronomy and physics.

Java Swing is not thread safe, and here are some related resources.

• Swing’s threading policy from package description
• Java SE Desktop Articles and tutorial Creating GUI
• SwingUtilities methods invokeAndWait and invokeLater in an example at Java Revisited blog
• Building thread safe GUIs at Java Developers Journal resource CD vol 6 issue 5 – swing
• SwingUtilities.invokeAndWait with return value using Callable

Representational State Transfer (REST) is an architectural style for creating, maintaining, retrieving, and deleting resources. REST’s information-driven, resource-oriented approach to building Web services can both satisfy your software’s users and make your life as a developer easier. Web services that allow the retrieval and modification of logically named resources that mean something to someone is what REST is about. REST concept for Java developers is well described in JawaWorld articles from Brian Sletten (part1, part2, part3, part4).