Oftentimes, an application is packaged as a jar file. Ususally, you have to use a command line option to execute it. It would be easier to double click on the jar file to get the application to run, instead of typing a command. To do this, you need a manifest file that specifies the Main class of the application as given below:
Manifest-Version: 1.0Main-Class: com.xxx.yyy.main.ALoginDialogCreated-By: 1.3.0_01 (Sun Microsystems Inc.)
The following command will create the executable jar:
jar cfm myappln.jar Manifest.mf com
Here, myappln.jar is the name of the executable jar file. Manifest.mf is the name of the manifest file and com is the base directory containing the classes.