001    /* Copyright 2000, 2001, Compaq Computer Corporation */
002    
003    /* IF THIS IS A JAVA FILE, DO NOT EDIT IT!  
004    
005       Most Java files in this directory which are part of the Javafe AST
006       are automatically generated using the astgen comment (see
007       ESCTools/Javafe/astgen) from the input file 'hierarchy.h'.  If you
008       wish to modify AST classes or introduce new ones, modify
009       'hierarchy.j.'
010     */
011    
012    package javafe.ast;
013    
014    import javafe.util.Assert;
015    import javafe.util.Location;
016    import javafe.util.ErrorSet;
017    
018    // Convention: unless otherwise noted, integer fields named "loc" refer
019    // to the location of the first character of the syntactic unit
020    
021    
022    /**
023     * Represents various kinds of field access expressions. 
024     * The FieldDecl is filled in by the name resolution code.
025     */
026    
027    public class FieldAccess extends Expr
028    {
029      public /*@ non_null @*/ ObjectDesignator od;
030    
031      public /*@ non_null @*/ Identifier id;
032    
033      //@ invariant locId != javafe.util.Location.NULL;
034      public int locId;
035    
036    
037      //@ invariant decl == null || decl.id==id;
038      public FieldDecl decl;
039    
040      private void postCheck() {
041        if (decl != null) {
042          Assert.notFalse(id == decl.id);
043          // Any other invariants here...???
044        }
045      }
046      public int getStartLoc() { 
047        int locOd = od.getStartLoc();
048        if (locOd == Location.NULL) 
049          return locId;
050        else
051          return locOd;
052      }
053      public int getEndLoc() { return locId; }
054    
055      //@ requires locId != javafe.util.Location.NULL;
056      //@ ensures \result != null;
057      public static FieldAccess make(/*@ non_null @*/ ObjectDesignator od, 
058                                     /*@ non_null @*/ Identifier id, 
059                                     int locId) {
060         //@ set I_will_establish_invariants_afterwards = true;
061         FieldAccess result = new FieldAccess();
062         result.od = od;
063         result.id = id;
064         result.locId = locId;
065         result.decl = null;  // Easier than puting an ensures on constructor
066         return result;
067      }
068    
069    
070    // Generated boilerplate constructors:
071    
072      /**
073       * Construct a raw FieldAccess whose class invariant(s) have not
074       * yet been established.  It is the caller's job to
075       * initialize the returned node's fields so that any
076       * class invariants hold.
077       */
078      //@ requires I_will_establish_invariants_afterwards;
079      protected FieldAccess() {}    //@ nowarn Invariant,NonNullInit;
080    
081    
082    // Generated boilerplate methods:
083    
084      public final int childCount() {
085         return 2;
086      }
087    
088      public final Object childAt(int index) {
089              /*throws IndexOutOfBoundsException*/
090         if (index < 0)
091            throw new IndexOutOfBoundsException("AST child index " + index);
092         int indexPre = index;
093    
094         int sz;
095    
096         if (index == 0) return this.od;
097         else index--;
098    
099         if (index == 0) return this.id;
100         else index--;
101    
102         throw new IndexOutOfBoundsException("AST child index " + indexPre);
103      }   //@ nowarn Exception;
104    
105      public final String toString() {
106         return "[FieldAccess"
107            + " od = " + this.od
108            + " id = " + this.id
109            + " locId = " + this.locId
110            + "]";
111      }
112    
113      public final int getTag() {
114         return TagConstants.FIELDACCESS;
115      }
116    
117      public final void accept(Visitor v) { v.visitFieldAccess(this); }
118    
119      public final Object accept(VisitorArgResult v, Object o) {return v.visitFieldAccess(this, o); }
120    
121      public void check() {
122         super.check();
123         this.od.check();
124         if (this.id == null) throw new RuntimeException();
125         postCheck();
126      }
127    
128    }