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Jodd Core tools and utilities, including type converters, JDateTime, cache etc.

There is a newer version: 5.3.0

// Copyright (c) 2003-2014, Jodd Team (jodd.org). All Rights Reserved.

package jodd.typeconverter.impl;

import jodd.typeconverter.TypeConversionException;
import jodd.typeconverter.TypeConverter;
import jodd.util.StringUtil;

/**
 * Converts given object to Double.
 * Conversion rules:
 * 
 * null value is returned as null
 * object of destination type is simply casted
 * object is converted to string, trimmed, and then converted if possible.
 * 
 * Number string may start with plus and minus sign.
 */
public class DoubleConverter implements TypeConverter {

	public Double convert(Object value) {
		if (value == null) {
			return null;
		}

		if (value.getClass() == Double.class) {
			return (Double) value;
		}
		if (value instanceof Number) {
			return Double.valueOf(((Number)value).doubleValue());
		}

		try {
			String stringValue = value.toString().trim();
			if (StringUtil.startsWithChar(stringValue, '+')) {
				stringValue = stringValue.substring(1);
			}
			return Double.valueOf(stringValue);
		} catch (NumberFormatException nfex) {
			throw new TypeConversionException(value, nfex);
		}
	}

}