package org.drools.semantics.python;
/*
* $Id: PythonExprAnalyzer.java,v 1.2 2005/02/04 02:13:38 mproctor Exp $
*
* Copyright 2002 (C) The Werken Company. All Rights Reserved.
*
* Redistribution and use of this software and associated documentation
* ("Software"), with or without modification, are permitted provided that the
* following conditions are met:
*
* 1. Redistributions of source code must retain copyright statements and
* notices. Redistributions must also contain a copy of this document.
*
* 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 name "drools" must not be used to endorse or promote products derived
* from this Software without prior written permission of The Werken Company.
* For written permission, please contact bob@werken.com.
*
* 4. Products derived from this Software may not be called "drools" nor may
* "drools" appear in their names without prior written permission of The Werken
* Company. "drools" is a registered trademark of The Werken Company.
*
* 5. Due credit should be given to The Werken Company.
* (http://drools.werken.com/).
*
* THIS SOFTWARE IS PROVIDED BY THE WERKEN COMPANY AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE WERKEN COMPANY OR ITS CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND 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.
*
*/
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.drools.rule.Declaration;
import org.python.parser.ast.modType;
/**
* Analyzes python expressions for all mentioned variables.
*
* @author <a href="mailto:bob@eng.werken.com">bob mcwhirter </a>
*/
public class PythonExprAnalyzer
{
// ------------------------------------------------------------
// Constructors
// ------------------------------------------------------------
/**
* Construct.
*/
public PythonExprAnalyzer()
{
// intentionally left blank
}
// ------------------------------------------------------------
// Instance methods
// ------------------------------------------------------------
/**
* Analyze an expression.
*
* @param expr The expression to analyze.
* @param availDecls Total set of declarations available.
*
* @return The array of declarations used by the expression.
*
* @throws Exception If an error occurs while attempting to analyze the
* expression.
*/
public Declaration[] analyze( modType expr,
List availDecls ) throws Exception
{
PythonExprVisitor visitor = new PythonExprVisitor( );
List decls = new ArrayList( );
Set refs = ( Set ) visitor.eval_input( expr );
Iterator declIter = availDecls.iterator( );
Declaration eachDecl;
while ( declIter.hasNext( ) )
{
eachDecl = ( Declaration ) declIter.next( );
if ( refs.contains( eachDecl.getIdentifier( ) ) )
{
decls.add( eachDecl );
refs.remove( eachDecl.getIdentifier( ) );
}
}
return ( Declaration[] ) decls.toArray( new Declaration[ decls.size( ) ] );
}
}