/*
 * ReturnStatement.java 1.0
 *
 *
 * Jun 20, 1997 by mich
 * Sep 29, 1997 by bv
 * Oct 11, 1997 by mich
 *
 * @see io.devnulllabs.openjava.ptree.ParseTree
 * @version 1.0 last updated:  Oct 11, 1997
 * @author  Michiaki Tatsubori
 */
package io.devnulllabs.openjava.ptree;

import io.devnulllabs.openjava.ptree.util.ParseTreeVisitor;

/**
 * The <code>ReturnStatement</code> class represents
 * a return statement node of parse tree.
 *
 * @see io.devnulllabs.openjava.ptree.ParseTree
 * @see io.devnulllabs.openjava.ptree.NonLeaf
 * @see io.devnulllabs.openjava.ptree.Statement
 */
public class ReturnStatement extends NonLeaf implements Statement, ParseTree {
    /**
     * Allocates a new object.
     *
     * @param  expr  the expression to be returned by this statement.
     *               If this is null, nothing to be returned.
     */
    public ReturnStatement(Expression expr) {
        super();
        set((ParseTree) expr);
    }

    /**
     * Allocates a new object.
     *
     */
    public ReturnStatement() {
        this(null);
    }

    /**
     * Gets the returned expression by this statement.
     *
     * @return  the expression to be returned by this statement.
     */
    public Expression getExpression() {
        return (Expression) elementAt(0);
    }

    /**
     * Sets the returned expression by this statement.
     *
     * @param  expr  the expression to be returned by this statement.
     */
    public void setExpression(Expression expr) {
        setElementAt(expr, 0);
    }

    public void accept(ParseTreeVisitor v) throws ParseTreeException {
        v.visit(this);
    }

}