001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.math.util;
018    
019    import org.apache.commons.math.MathException;
020    
021    /**
022     * Subclasses implementing this interface can transform Objects to doubles.
023     * @version $Revision: 811685 $ $Date: 2009-09-05 19:36:48 +0200 (sam. 05 sept. 2009) $
024     *
025     * No longer extends Serializable since 2.0
026     *
027     */
028    public interface NumberTransformer {
029    
030        /**
031         * Implementing this interface provides a facility to transform
032         * from Object to Double.
033         *
034         * @param o the Object to be transformed.
035         * @return the double value of the Object.
036         * @throws MathException if the Object can not be transformed into a Double.
037         */
038        double transform(Object o) throws MathException;
039    }