ClassLit_c.java

/*
 *  This file is part of the X10 project (http://x10-lang.org).
 *
 *  This file is licensed to You under the Eclipse Public License (EPL);
 *  You may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *      http://www.opensource.org/licenses/eclipse-1.0.php
 *
 * This file was originally derived from the Polyglot extensible compiler framework.
 *
 *  (C) Copyright 2000-2007 Polyglot project group, Cornell University
 *  (C) Copyright IBM Corporation 2007-2012.
 */

package polyglot.ast;

import java.util.List;

import polyglot.types.SemanticException;
import polyglot.util.CodeWriter;
import polyglot.util.Position;
import polyglot.visit.*;
import x10.types.constants.ConstantValue;

/**
 * A <code>ClassLit</code> represents a class literal expression. 
 * A class literal expressions is an expression consisting of the 
 * name of a class, interface, array, or primitive type followed by a period (.) 
 * and the token class. 
 */
public class ClassLit_c extends Lit_c implements ClassLit
{
  protected TypeNode typeNode;

  public ClassLit_c(Position pos, TypeNode typeNode) {
    super(pos);
    assert(typeNode != null);
    this.typeNode = typeNode;
  }

  public TypeNode typeNode() {
    return this.typeNode;
  }

  public ClassLit typeNode(TypeNode typeNode) {
      if (this.typeNode == typeNode) {
          return this;
      }
    ClassLit_c n = (ClassLit_c) copy();
    n.typeNode = typeNode;
    return n;
  }
    
  /**
   * Cannot return the correct object (except for maybe
   * some of the primitive arrays), so we just return null here. 
   */
  public Object objValue() {
    return null;
  }

  public Term firstChild() {
      return typeNode;
  }

  public <S> List<S> acceptCFG(CFGBuilder v, List<S> succs) {
      v.visitCFG(typeNode, this, EXIT);
      return succs;
  }

  public Node visitChildren(NodeVisitor v) {
    TypeNode tn = (TypeNode)visitChild(this.typeNode, v);
    return this.typeNode(tn);
  }

  /** Type check the expression. */
  public Node typeCheck(ContextVisitor tc) {
    return type(tc.typeSystem().Class());
  }

  public String toString() {
    return typeNode.toString() + ".class";
  }

  /** Write the expression to an output file. */
  public void prettyPrint(CodeWriter w, PrettyPrinter tr)
  {
    w.begin(0);
    print(typeNode, w, tr);
    w.write(".class");
    w.end();
  }

  /**
   * According to the JLS 2nd Ed, sec 15.28, a class literal 
   * is not a compile time constant.
   */
  public boolean isConstant() {
    return false;
  }

  public ConstantValue constantValue() {
    return null;
  }

}