/*
* 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.math3.util;
import java.io.Serializable;
import org.apache.commons.math3.exception.util.LocalizedFormats;
import org.apache.commons.math3.exception.MathIllegalArgumentException;
import org.apache.commons.math3.exception.NullArgumentException;
/**
* 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.
*
*/
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 NullArgumentException if Object <code>o</code> is {@code null}.
* @throws MathIllegalArgumentException if Object <code>o</code>
* cannot successfully be transformed
* @see <a href="http://commons.apache.org/collections/api-release/org/apache/commons/collections/Transformer.html">Commons Collections Transformer</a>
*/
public double transform(Object o)
throws NullArgumentException, MathIllegalArgumentException {
if (o == null) {
throw new NullArgumentException(LocalizedFormats.OBJECT_TRANSFORMATION);
}
if (o instanceof Number) {
return ((Number)o).doubleValue();
}
try {
return Double.parseDouble(o.toString());
} catch (NumberFormatException e) {
throw new MathIllegalArgumentException(LocalizedFormats.CANNOT_TRANSFORM_TO_DOUBLE,
o.toString());
}
}
/** {@inheritDoc} */
@Override
public boolean equals(Object other) {
if (this == other) {
return true;
}
return other instanceof DefaultTransformer;
}
/** {@inheritDoc} */
@Override
public int hashCode() {
// some arbitrary number ...
return 401993047;
}
}