env variable or so

[michael modenese]

hi there,
i have 2 java applications and one needs to check if the other is still running by setting a variable and wait, so in the meantime the other application can change the value of the same variable, so to prove that it is still running. each application has a thread doing this checking.
any idea what mechanism i can use for storing this variable ? is there something like a env.variable i can use ? ore properties stored outside the java applications ? i would prefer not to use a file....

thx

[Jeff Albertson]

One standard way for processes to communicate is through sockets.

[Ajith Kallambella]

Are both the apps running in the same JVM? Is so, you could use a third entity, like a Singleton to hold the variable. If they are running in different JVMs, you have to resort to something that they both can access - like a file.

Here's another thought - instead of applications querying for the "state", why not use a Mediator - something that tells each interested app that the state has changed? Since I don't know the details of your apps, I cannot fathom whether this strategy translates to an over-engineered solution.