src/java/org/apache/velocity/runtime/parser/node/ASTGENode.java

package org.apache.velocity.runtime.parser.node;

/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000-2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Velocity", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
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 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
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 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import org.apache.velocity.context.InternalContextAdapter;
import org.apache.velocity.runtime.parser.Parser;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.runtime.Runtime;

public class ASTGENode extends SimpleNode
{
    public ASTGENode(int id)
    {
        super(id);
    }

    public ASTGENode(Parser p, int id)
    {
        super(p, id);
    }

    /** Accept the visitor. **/
    public Object jjtAccept(ParserVisitor visitor, Object data)
    {
        return visitor.visit(this, data);
    }

    public boolean evaluate( InternalContextAdapter context)
        throws MethodInvocationException
    {
        /*
         *  get the two args
         */

        Object left = jjtGetChild(0).value( context );
        Object right = jjtGetChild(1).value( context );

        /*
         *  if either is null, lets log and bail
         */

        if (left == null || right == null)
        {
            Runtime.error( ( left == null ? "Left" : "Right" ) 
                           + " side of '>=' operation has null value."
                           + " Operation not possible. "
                           + context.getCurrentTemplateName() + " [line " 
                           + getLine() 
                           + ", column " + getColumn() + "]");
            return false;
        }
        
        /*
         *  if not an Integer, not much we can do either
         */

        if ( !( left instanceof Integer )  || !( right instanceof Integer ))
        {
            Runtime.error( ( !( left instanceof Integer ) ? "Left" : "Right" ) 
                           + " side of '>=' operation is not a valid type. "
                           + " It is a " + ( !( left instanceof Integer ) ? left.getClass() : right.getClass() ) 
                           + ". Currently only integers (1,2,3...) and Integer type is supported. "
                           +  context.getCurrentTemplateName() + " [line " + getLine() 
                           + ", column " + getColumn() + "]");
 
            return false;
        }

        return ( (Integer) left).intValue() >=  ((Integer) right).intValue(); 
     
    }
}