Final COM 1205
Fall 2002
====================================================
Open book and open notes, 1.45 hour exam

Question 1: Parsing and Printing
69 UNKNOWNs:
87 points

Question 2: Class Dictionary Design
11 UNKNOWNs: 6 points each:
66 points

Question 3: Executing a Small Program
27 UNKNOWNs: 5 points each
135 points
==============
288 points total


Question 1: Parsing and Printing
========================================================
69 UNKNOWNs:

UNKNOWN 1 - 67: 1 points each
UNKNOWN68: 10 points
UNKNOWN69: 10 points
---------------
87 points total

Consider the following class dictionary program.cd, behavior file
program.beh and program.input.
Find the UNKNOWNs. 
This is an easy question about parsing and printing.

// class dictionary cd1

DAJ = List(TraversalAspect).
TraversalAspect = "aspect" AspectName <decls> CurlyList(Definition).
Definition = "declare" DefinitionBody ";".
DefinitionBody : CG | Strategy | AdaptiveMethod.
CG = "ClassGraph" ClassGraphName.
Strategy = "Strategy" StrategyName "=" StrategyExpression.
StrategyExpression = StrategyName.
AdaptiveMethod = "Method" MethodSignature MethodBody.
MethodSignature = 
  <keywords> List(MethodKeyword)
  <returnType> JavaType <name> MethodName
  "(" [ <parms> Commalist(MethodParm) ] ")"
  <throwsclause> Throws.
MethodKeyword : PublicMethod | ProtectedMethod | PrivateMethod
	        | StaticMethod | FinalMethod .
PublicMethod            = "public".
ProtectedMethod         = "protected".
PrivateMethod           = "private".
StaticMethod            = "static".
FinalMethod             = "final".
MethodParm              = <type> JavaType <name> ParmName
  <array> List(ArraySpec).
Throws          = [ *s "throws" <exceptions> Commalist(ClassName) ].
MethodBody      = <trv> StrategyExpression <vis> VisitorRef.
VisitorRef      = "(" <visitorClasses> Commalist(ClassName) ")" .

JavaType        = <type> Name <array> List(ArraySpec).
ArraySpec       = "[" "]".

Name ~ Ident { "." Ident }.
ClassGraphName = Ident.
StrategyName = Ident.
MethodName = Ident.
ClassName = Name.
ParmName = <name> Ident.
AspectName = Name.

List(S) ~ {*s S}.
NList(S) ~ S {*s S}.
CurlyList(S) ~ "{" S {*s S} "}".
Commalist(S) ~ S {"," *s S}.

Main = <s> String.

//========================================================
// program.beh

Main {
  public static void main(String args[]) throws Exception {{
    DAJ m = DAJ.parse(System.in);
    m.display();
    System.out.println("done");
  }}
}

DAJ {
  void display() bypassing -> *,parent,* to * (DisplayVisitor);
}

//========================================================
// program.input

aspect A {
  declare ClassGraph cg;
  declare Strategy s1 = s2;
  declare Method public final static R f(A a) s1(V1,V2); 
}

UNKNOWN69

//========================================================
// output


: DAJ  (
 <traversalaspect_list> : TraversalAspect_List  {
  <first> : Nonempty_TraversalAspect_List  (
   <it> : UNKNOWN1  (
    <UNKNOWN2> : UNKNOWN3  (
     <UNKNOWN4> : UNKNOWN5  {
      <first> : Nonempty_Name  (
       <it>  : Ident "UNKNOWN6" ) } )
    <decls> : Definition_CurlyList  {
     <first> : Nonempty_Definition_CurlyList  (
      <it> : UNKNOWN7  (
       <definitionbody> : UNKNOWN8  (
        <classgraphname> : UNKNOWN9  (
         <UNKNOWN10>  : UNKNOWN11 "UNKNOWN12" ) ) )
      <next> : Nonempty_Definition_CurlyList  (
       <it> : UNKNOWN13  (
        <UNKNOWN14> : UNKNOWN15  (
         <UNKNOWN16> : UNKNOWN17  (
          <ident>  : Ident "UNKNOWN18" )
         <UNKNOWN19> : UNKNOWN20  (
          <UNKNOWN21> : UNKNOWN22  (
           <UNKNOWN23>  : UNKNOWN24 "UNKNOWN25" ) ) ) )
       <next> : Nonempty_Definition_CurlyList  (
        <it> : UNKNOWN26  (
         <definitionbody> : UNKNOWN27  (
          <methodsignature> : UNKNOWN28  (
           <keywords> : MethodKeyword_List  {
            <first> : Nonempty_MethodKeyword_List  (
             <it> : UNKNOWN29  ( )
             <next> : Nonempty_MethodKeyword_List  (
              <it> : UNKNOWN30  ( )
              <next> : Nonempty_MethodKeyword_List  (
              <it> : UNKNOWN31  ( ) ) ) ) }
           <returnType> : UNKNOWN32  (
            <type> : UNKNOWN33  {
             <first> : Nonempty_Name  (
              <it>  : Ident "UNKNOWN34" ) }
            <array> : UNKNOWN35  { } )
           <UNKNOWN36> : UNKNOWN37  (
            <UNKNOWN38>  : UNKNOWN39 "UNKNOWN40" )
           <parms> : MethodParm_Commalist  {
            <first> : Nonempty_MethodParm_Commalist  (
             <it> : UNKNOWN41  (
              <UNKNOWN42> : UNKNOWN43  (
               <type> : UNKNOWN44  {
                <first> : Nonempty_Name  (
                 <it>  : UNKNOWN45 "UNKNOWN46" ) }
               <array> : ArraySpec_List  { } )
              <name> : UNKNOWN47  (
               <name>  : Ident "UNKNOWN48" )
              <array> : UNKNOWN49  { } ) ) }
           <throwsclause> : UNKNOWN50  ( ) )
          <UNKNOWN51> : UNKNOWN52  (
           <UNKNOWN53> : UNKNOWN54  (
            <UNKNOWN55> : UNKNOWN56  (
             <ident>  : Ident "UNKNOWN57" ) )
           <vis> : UNKNOWN58  (
            <UNKNOWN59> : ClassName_Commalist  {
             <first> : Nonempty_ClassName_Commalist  (
              <it> : UNKNOWN60  (
               <name> : UNKNOWN61  {
                <first> : Nonempty_Name  (
                 <it>  : UNKNOWN62 "UNKNOWN63" ) } )
              <next> : Nonempty_ClassName_Commalist  (
               <it> : UNKNOWN64  (
                <UNKNOWN65> : UNKNOWN66  {
                 <first> : Nonempty_Name  (
                  <it>  : Ident "UNKNOWN67" ) } ) ) ) } ) ) ) ) ) ) ) } )
   <next> : Nonempty_TraversalAspect_List  (
    <it> : TraversalAspect  (
     <aspectname> : AspectName  (
      <name> : Name  {
       <first> : Nonempty_Name  (
        <it>  : Ident "B" ) } )
     <decls> : Definition_CurlyList  {
      <first> : Nonempty_Definition_CurlyList  (
       <it> : Definition  (
        <definitionbody> : CG  (
         <classgraphname> : ClassGraphName  (
          <ident>  : Ident "cg" ) ) ) ) } ) ) ) } )done
// ================================================

Additonal question about this class dictionary and behavior file: 
What is the output for the following input in program.input:

aspect B { }

Explain your answer in UNKNOWN68.


Question 2: Class Dictionary Design
====================================================
11 UNKNOWNs: 6 points each:
66 points

Consider the class dictionary cd1 from question 1.
Extend the class dictionary so that the class dictionary
accepts the following input in program.input.


aspect A {
  declare ClassGraph cg;
  declare Strategy s1 = "from * bypassing -> *,tail,* to *";
  declare Method public final static R f(A a) 
    (&& s1 "from A to B") (V1,V2); 
  declare Method public final static R f(A a) 
    (|| (&& s1 "from A to B") "from A via X to C") (V1,V2); 
}

aspect B {
  declare ClassGraph cg;
  declare Strategy s1 = "from * bypassing -> *,tail,* to *";
  declare Strategy s2 = "from * bypassing -> *,tail,* to *";
  declare Strategy s3 = ( && s1 s2);
  declare Strategy s4 = ( || s3 s2);
  declare Strategy s4 = ( ! s3 );
}

Replace the following line from class dictionary 1:

StrategyExpression = StrategyName.

by the following lines:

StrategyExpression : Simple | UNKNOWN1.
UNKNOWN2 : StrategyName | UNKNOWN3.
UNKNOWN4 = "UNKNOWN5" UNKNOWN6 List(UNKNOWN7) "UNKNOWN8".
Op : And | Or | Not.
And = "UNKNOWN9".
Or  = "||".
UNKNOWN10 = "!".
UNKNOWN11 = String.

Find the UNKNOWNs.
Note that for some UNKNOWNs multiple answers are correct.


Question 3: Executing a Small Program
======================================================
27 UNKNOWNs: 5 points each
135 points

We reuse the class dictionary cd1 from question 1
in the program.beh file below.
We enhance the class dictionary with the class definition:

ArraySpecChoiceVisitor = extends Visitor.

The input in program.input is:

aspect A {
  declare ClassGraph cg;
  declare Strategy s1 = s2;
  declare Method public final static R f(A[][] a[][]) s1(V1,V2); 
}

Find the UNKNOWNs in the output.
Note that ArraySpec@551f60 is an object identifier:
the identifier at the beginning gives the name of the class.

////////////////////////////////////
//program.beh

Main {
  {{
  static ClassGraph cg2;
  public static void main(String args[]) throws Exception {
    DAJ m = DAJ.parse(System.in);
    ClassGraph cg1 = new ClassGraph(true,false);
    cg2 = new ClassGraph(cg1, "from * bypassing ->*,tail,* to *");
    m.chooseArraySpec();
    System.out.println("done");
  }
  }}
}

JavaType {
  void print() to * (PrintVisitor);
}

DAJ {
  {{
  void chooseArraySpec(){
    ArraySpecChoiceVisitor v = new ArraySpecChoiceVisitor();
    Main.cg2.traverse(this, "from DAJ via JavaType to ArraySpec", v);
    System.out.println();
    System.out.println("================================");
    Main.cg2.traverse(this, "from DAJ bypassing JavaType to ArraySpec", v);
    System.out.println("================================");
    Main.cg2.traverse(this, "from DAJ to ArraySpec", v);
  }
  }}
}

ArraySpecChoiceVisitor {
  {{
      public void start(){
	System.out.println("Traversal Started ");
      }
      public void before(DAJ host){
	System.out.println(host);
      }
      public void before(MethodParm host){
	System.out.println(host);
      }
      public void before(JavaType host){
	host.print();
	System.out.println();
	System.out.println(host);
      }
      public void before(ArraySpec host){
	System.out.println(host);
      }
  }}
}

////////////////////////////////////
//output

Reading project file program.prj...
Running the test...
UNKNOWN1 
UNKNOWN2@763f5d
UNKNOWN3
UNKNOWN4@6768e
UNKNOWN5@519bc8
UNKNOWN6
UNKNOWN7@4a8cd1
UNKNOWN8@630ab9
UNKNOWN9@551f60

================================
UNKNOWN10 
UNKNOWN11@763f5d
UNKNOWN12@519bc8
UNKNOWN13@7ee8b8
UNKNOWN14@60b6f5
================================
UNKNOWN15 
UNKNOWN16@763f5d
UNKNOWN17
UNKNOWN18@6768e
UNKNOWN19@519bc8
UNKNOWN20
UNKNOWN21@4a8cd1
UNKNOWN22@630ab9
UNKNOWN23@551f60
UNKNOWN24@7ee8b8
UNKNOWN25@60b6f5
UNKNOWN26

// end of output
// additional question
Is it ok to switch in class Main the two lines:

cg2 = new ClassGraph(cg1, "from * bypassing ->*,tail,* to *");
m.chooseArraySpec();
?
Justify your answer with one sentence in UNKNOWN27.