for(int i  = 0; i< ffighters.size(); i++) {
      fFighter ff = (fFighter)ffighters.get(i); 
      if(ff.moving){
        ff.moving = false;
      }
      else{
        ff.moving = true;
      }
}

edit:you also don't want to break...

If you've seen for loops that start off with [int i = myArrayList.size()-1] or [int i = myArray.length - 1] they were probably moving backwards through the array/ArrayList:

1. String[] foo = {"a", "b", "c", "d", "e"};
2. for(int i=foo.length-1; i>-1; i--){
3.   println(foo[i]);
4. }

Assuming you want to move forward through your array bjordal's example is spot on; though if you just want to invert the value of the boolean you should be able to do the following rather than using the conditions:

1. for(int i  = 0; i< ffighters.size(); i++) {
2.   fFighter ff = (fFighter)ffighters.get(i); 
3.   ff.moving = !ff.moving;
4. }

! is the NOT operator and rather handy in this context ;)

thank you both, much appreciated =)