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     * We represent [C.]this.
024     *
025     * <p> classPrefix holds C if present, and null otherwise.
026     *
027     * @note classPrefix will hold a <em>**TypeSig**</em> instead of a
028     * TypeName if we have been inferred.  (The inferred field specifies
029     * whether or not we have been inferred.)
030     */
031    
032    public class ThisExpr extends Expr
033    {
034      public Type classPrefix;
035    
036    
037      //@ invariant loc != javafe.util.Location.NULL;
038      public int loc;
039    
040    
041      //* Were we inferred by the disambiguation code?
042      public boolean inferred = false;
043    
044        public int getStartLoc() {
045            if (classPrefix != null && classPrefix instanceof TypeName)
046                return classPrefix.getStartLoc();
047            return loc;
048        }
049    
050      public int getEndLoc() { return Location.inc(loc, 3); }
051    
052    
053    // Generated boilerplate constructors:
054    
055      /**
056       * Construct a raw ThisExpr whose class invariant(s) have not
057       * yet been established.  It is the caller's job to
058       * initialize the returned node's fields so that any
059       * class invariants hold.
060       */
061      //@ requires I_will_establish_invariants_afterwards;
062      protected ThisExpr() {}    //@ nowarn Invariant,NonNullInit;
063    
064    
065    // Generated boilerplate methods:
066    
067      public final int childCount() {
068         return 1;
069      }
070    
071      public final Object childAt(int index) {
072              /*throws IndexOutOfBoundsException*/
073         if (index < 0)
074            throw new IndexOutOfBoundsException("AST child index " + index);
075         int indexPre = index;
076    
077         int sz;
078    
079         if (index == 0) return this.classPrefix;
080         else index--;
081    
082         throw new IndexOutOfBoundsException("AST child index " + indexPre);
083      }   //@ nowarn Exception;
084    
085      public final String toString() {
086         return "[ThisExpr"
087            + " classPrefix = " + this.classPrefix
088            + " loc = " + this.loc
089            + "]";
090      }
091    
092      public final int getTag() {
093         return TagConstants.THISEXPR;
094      }
095    
096      public final void accept(Visitor v) { v.visitThisExpr(this); }
097    
098      public final Object accept(VisitorArgResult v, Object o) {return v.visitThisExpr(this, o); }
099    
100      public void check() {
101         super.check();
102         if (this.classPrefix != null)
103            this.classPrefix.check();
104      }
105    
106      //@ requires loc != javafe.util.Location.NULL;
107      //@ ensures \result != null;
108      public static ThisExpr make(Type classPrefix, int loc) {
109         //@ set I_will_establish_invariants_afterwards = true;
110         ThisExpr result = new ThisExpr();
111         result.classPrefix = classPrefix;
112         result.loc = loc;
113         return result;
114      }
115    }