Activation Asymmetry

Definition:

A default activation has no matching subsequent deactivation in the same statement block, or a deactivation has no matching previous activation.

Code Example:

 altstep myAltstep (timer t) runs on MyComponent {
   [] any port.receive {
     setverdict(fail)
     log ("unexpected message")
   }
   [] t.timeout{
     setverdict(fail)
     log("timeout")
   }
 }

 function activateDefault(timer t) return default {
   // no deactivation in this function!
   return act ivate ( myAltstep ( t ) )
 }

 testcase myTestcase1 ( ) runs on MyComponent {
   timer t
   var default myDefaultVar := activate(myAltstep(t))
   t.start(10.0)
   alt{
     [] p.receive(charstring:("foo1")){
       p.send("ack")
     }
     [] p.receive(charstring:("bar1")) {
       p.send("nack")
     }
   }
   deactivate(myDefaultVar)
 }

testcase myTestcase2 () runs on MyComponent {
 timer t;
 // activation in function call
 var default myDefaultVar := activateDefault(t)
   t.start(10.0)
   alt {
     []p.receive(charstring:("foo2")) {
       p.send("ack")
     }
     []p.receive(charstring:("bar2")) {
       p.send("nack")
     }
   }
   deactivate (myDefaultVar)
 }

 testcase myTestcase3 ( ) runs on MyComponent {
   // deactivation in different statement blocks
   timer t
   var default myDefaultVar
   myDefaultVar := activate(myAltstep(t))
   t.start(10.0)

   if(2 > 1) {
     alt {
       [] p.receive(charstring:("foo5")){
         p.send("ack")
       }[] p.receive(charstring:("bar5")){
         p.send("nack")
       }
     }
     deactivate ( myDefaultVar )
   }
 }

References:

Quality attributes

- Code Example
- Cause and Effect
- Frequency
- Refactoring