问jheatbugs-2001-03-28中某些代码

sybbk

HeatbugModelSwarm中buildActions部分，3个try分别是做什么？查了下refbook-java-2.2，解释太简略，还是不懂，高手指点，谢谢！代码如下：

public Object buildActions () {
    super.buildActions();
   
    // Create the list of simulation actions. We put these in
    // an action group, because we want these actions to be
8 j* e) c: i$ U1 \+ d8 M7 ]- W; p    // executed in a specific order, but these steps should
    // take no (simulated) time. The M(foo) means "The message
    // called <foo>". You can send a message To a particular
    // object, or ForEach object in a collection.
        
    // Note we update the heatspace in two phases: first run
    // diffusion, then run "updateWorld" to actually enact the
# _+ W) q, B" Y" {( b    // changes the heatbugs have made. The ordering here is
    // significant!
3 h& d/ r6 [' F/ d2 T; g! B        
    // Note also, that with the additional
    // `randomizeHeatbugUpdateOrder' Boolean flag we can
. d* [3 |2 T+ `/ X+ N6 E    // randomize the order in which the bugs actually run
    // their step rule.  This has the effect of removing any
    // systematic bias in the iteration throught the heatbug
! j* Y) c( Q) g9 m    // list from timestep to timestep
        
    // By default, all `createActionForEach' modelActions have
" _' W3 L- ~' j+ A6 k. g+ ~    // a default order of `Sequential', which means that the
, k. L' m; W+ x( h# {8 q3 a4 t5 i    // order of iteration through the `heatbugList' will be
    // identical (assuming the list order is not changed
    // indirectly by some other process).
   
    modelActions = new ActionGroupImpl (getZone ());
6 b7 a4 ?5 B  f' p, I4 e
) \/ j! |3 Y% \0 `* V( `    try {
      modelActions.createActionTo$message
# @9 Y# P+ |0 d0 P        (heat, new Selector (heat.getClass (), "stepRule", false));
# O: V0 D  z" j: C    } catch (Exception e) {
& m4 ]' H: Q0 g% t      System.err.println ("Exception stepRule: " + e.getMessage ());
    }

    try {
. C3 m0 x1 a: k, K  A      Heatbug proto = (Heatbug) heatbugList.get (0);
      Selector sel =
        new Selector (proto.getClass (), "heatbugStep", false);
      actionForEach =
# M1 q$ G+ a% Q2 ]3 `9 o9 }        modelActions.createFActionForEachHomogeneous$call
        (heatbugList,
: o& ~2 U+ ~: B" |/ h         new FCallImpl (this, proto, sel,
                        new FArgumentsImpl (this, sel)));
    } catch (Exception e) {
0 O# [& _1 d$ e6 g1 y' {# H3 y      e.printStackTrace (System.err);
    }
. Q0 m' ]! e# n7 U; h; C   
/ L0 n! D" d. l    syncUpdateOrder ();

    try {
: g9 p8 t" X7 A( B: u' T      modelActions.createActionTo$message
7 G4 K: }, f) O& R- n6 ^3 ^: F. n; o( I        (heat, new Selector (heat.getClass (), "updateLattice", false));
    } catch (Exception e) {
      System.err.println("Exception updateLattice: " + e.getMessage ());
6 @1 }3 ^& K3 R/ }/ E2 E    }
        
! j$ r; g. X6 M, X1 t    // Then we create a schedule that executes the
+ d+ l0 p! u+ S) M5 ^) Z& g, M8 J    // modelActions. modelActions is an ActionGroup, by itself it
    // has no notion of time. In order to have it executed in
) Z5 Z; y* m  _    // time, we create a Schedule that says to use the
    // modelActions ActionGroup at particular times.  This
    // schedule has a repeat interval of 1, it will loop every
    // time step.  The action is executed at time 0 relative to
    // the beginning of the loop.
8 }9 J& w% F$ C& ?5 O% M
    // This is a simple schedule, with only one action that is
    // just repeated every time. See jmousetrap for more
    // complicated schedules.
  
; F! c1 J/ R$ [. O. T    modelSchedule = new ScheduleImpl (getZone (), 1);
! X  h6 z. ]- F+ u8 a    modelSchedule.at$createAction (0, modelActions);
& J* g- O  b* c, X6 j# {/ g        
6 U+ Z, R" r8 l  F; i# g/ ~: q    return this;
4 F* R4 E# \3 d3 l) A  }