/*
 * @(#)$Id: ConcurExp.java,v 1.6 2003/12/12 21:36:38 kohsuke Exp $
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package com.sun.msv.grammar;

/**
 * &lt;concur&gt; pattern of TREX.
 * 
 * None of the other language needs this expression.
 * So application can deny processing this expression if neceesary,
 * without hampering the multi-schema-ness.
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
public final class ConcurExp extends BinaryExp {
    
    ConcurExp( Expression left, Expression right ) {
        super(left,right);
    }
    
    public Object visit( ExpressionVisitor visitor ) {
        return visitor.onConcur(this);
    }

    public Expression visit( ExpressionVisitorExpression visitor ) {
        return visitor.onConcur(this);
    }
    
    public boolean visit( ExpressionVisitorBoolean visitor ) {
        return visitor.onConcur(this);
    }

    public void visit( ExpressionVisitorVoid visitor ) {
        visitor.onConcur(this);
    }

    protected boolean calcEpsilonReducibility() {
        return exp1.isEpsilonReducible() && exp2.isEpsilonReducible();
    }
    
    // serialization support
    private static final long serialVersionUID = 1;    
}
