// To demonstrate how to translate class dictionaries
// into object displaying visitors
// in /proj/asl/lieber/java/java-envs/j-g-displayAsTree

A {
(@
  void g_displayAsTree() {
    TreeDisplayVisitor pv = new TreeDisplayVisitor(new Integer(0));
    this.t(pv);
  }
@)
// it is important that you traverse to all classes whose
// objects you want to display. If you forget to traverse to
// Y, Y-objects will not display. This is an advantage since
// you can control with the traversal specification what
// to display.
traversal t(TreeDisplayVisitor pv) { to {D,E,Y};}
  // could use to *;
}

Main {
(@
  static public void main(String args[]) throws Exception {

    A a = A.parse(System.in);

    a.g_displayAsTree();

    System.out.println("done ");
  }
@)
}

TreeDisplayVisitor{
(@
void spaces() {
  for 
    (int i=0;
     i < indent.intValue(); i++
    ) 
  {System.out.print(" ");}}
@)
(@
void incr() {
  this.set_indent(new Integer(this.get_indent().intValue() + 3));}
@)
(@
void decr() {
  this.set_indent(new Integer(this.get_indent().intValue() - 3));}
@)

// The class dictionary is translated systematically into
// a TreeDisplayVisitor. The class definition is printed
// for more context when reading the object.

// The class definition
// A = "a" <b> B <x> X "enda".
// is translated into the following two visitor methods
before A (@ spaces(); System.out.println(" A( = <b> B <x> X ");incr(); @)
after A (@ decr(); spaces(); System.out.println(" ) ");  @)

// B ~ "(" {C} ")".
before B (@ spaces(); System.out.println(" B{ ~ {C} "); incr(); @)
after B (@ decr(); spaces(); System.out.println(" } "); @)

// X = "x" Y.
before X (@ spaces(); System.out.println(" X( = Y"); incr(); @)
after X (@ decr(); spaces(); System.out.println(" ) ");  @)

// Y = .
before Y (@ spaces(); System.out.println(" Y( "); incr(); @)
after Y (@ decr(); spaces(); System.out.println(" ) ");  @)

// D = "d" Ident.
before D (@ spaces(); System.out.println(" D( = Ident"); incr();
	    spaces(); System.out.println(" Ident(" + host.get_ident() + ")"); @)
after D (@ decr(); spaces(); System.out.println(" ) ");  @)

// E = "e" Integer.
before E (@ spaces(); System.out.println(" E( = Integer"); incr();
	    spaces(); System.out.println(" Integer(" + 
	      host.get_integer().intValue() + ")"); @)
after E (@ decr(); spaces(); System.out.println(" ) ");  @)
}