org.apache.commons.math.util.DefaultTransformer Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of commons-math Show documentation

The Math project is a library of lightweight, self-contained mathematics and statistics components addressing the most common practical problems not immediately available in the Java programming language or commons-lang.

There is a newer version: 2.2

Show newest version

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.commons.math.util;

import java.io.Serializable;

import org.apache.commons.math.MathException;

/**
 * A Default NumberTransformer for java.lang.Numbers and Numeric Strings. This 
 * provides some simple conversion capabilities to turn any java.lang.Number 
 * into a primitive double or to turn a String representation of a Number into 
 * a double.
 *
 * @version $Revision: 800112 $ $Date: 2009-08-02 13:23:37 -0400 (Sun, 02 Aug 2009) $
 */
public class DefaultTransformer implements NumberTransformer, Serializable {
   
    /** Serializable version identifier */
    private static final long serialVersionUID = 4019938025047800455L;
    
    /**
     * @param o  the object that gets transformed.
     * @return a double primitive representation of the Object o.
     * @throws org.apache.commons.math.MathException If it cannot successfully 
     * be transformed or is null.
     * @see 
     */
    public double transform(Object o) throws MathException{

        if (o == null) {
            throw new MathException("Conversion Exception in Transformation, Object is null");
        }

        if (o instanceof Number) {
            return ((Number)o).doubleValue();
        }
            
        try {
            return Double.valueOf(o.toString()).doubleValue();
        } catch (Exception e) {
            throw new MathException(e,
                                    "Conversion Exception in Transformation: {0}", e.getMessage());
        }
    }

    /** {@inheritDoc} */
    @Override
    public boolean equals(Object other) {
        if (this == other) { 
            return true;
        }
        if (other == null) {
            return false;
        }
        return other instanceof DefaultTransformer;
    }
    
    /** {@inheritDoc} */
    @Override
    public int hashCode() {
        // some arbitrary number ...
        return 401993047;
    }

}