This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Hello Everybody, I am building a desktop application. The thing is that I don't want 2 references to the program in the memory, so the 2nd time the program tries to start it just doesn't start. I though of the following not working solution: Create a starter-class. This class should load the main-app class, built as a singleton. This didn't work, I think that every time the application is loaded, it will get a amount of memory, and isn't allowed to look into the other applications memory. Does any have a solution to this problem? I have been thinking about setting a flag using Preferences, and reading this out. But I think that when the application crashes or something like that, and the value isn't put back the way it is done when it is closed, the application couldn't be started anymore. Does someone have a better solution? Regards, Mark Monster
One trick (and I say trick because it is not an elegant solution) is to use a known system resource. The easiest is probably to open a java.net.ServerSocket on an unused port. Then if the application is loaded a second time then a BindException will be thrown when you try to bind the ServerSocket to the port. For example:
Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction. - Ernst F. Schumacher