Yes, a Java Runtime Environment does need to be present. With execJ, you can detect an installed JRE on the system and/or specify a local relative path to a JRE you include with your application.

The encryption used is a proprietary variant of RSA encryption. Encryption strengths ranging from 60-bit to 160-bit are available. The lower the encryption strength, the quicker your application will load. The encryption is designed to minimize the effect on load time. It is recommended for most applications to use either the 96-bit or 128-bit encryption for the best balance of security and speed.

Yes, execJ makes it easy to take any executable JAR and build an encrypted EXE or JAR application. Simply set your executable JAR file on the Project tab and specify a filename for your new application. Then build your program on the Build tab. However, it is not necessary to have an executable JAR to build an execJ project.

If your project application is named test.exe, you can simply execute the following command to add your service to the system as a manual startup service and start the service:

test.exe -addService -noauto -startService

Windows Services are available in Windows NT, 2000, XP, 2003, and Vista.

The execj.exe file can build projects in a command line mode by passing your execJ project files (.ejp) to the program as an argument such as:

execj.exe C:\myprojects\myproject.ejp

Programs built with the execJ trial version will stop working in 7 days and can only run for 24 hours at a time.