org.eclipse.osbp.runtime.web.vaadin.common/src/org/eclipse/osbp/runtime/web/vaadin/common/converter/StringToFormattedNumberConverter.java

package org.eclipse.osbp.runtime.web.vaadin.common.converter;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.util.Locale;

import org.apache.commons.lang3.StringEscapeUtils;

import com.vaadin.data.util.converter.AbstractStringToNumberConverter;

@SuppressWarnings("serial")
public class StringToFormattedNumberConverter extends
		AbstractStringToNumberConverter<Number> {
	private final String format;
	private final Class<? extends Number> resultType;

	public StringToFormattedNumberConverter(String format,
			Class<? extends Number> resultType) {
		this.format = format;
		this.resultType = resultType;
	}

	@Override
	public String convertToPresentation(Number value,
			Class<? extends String> targetType, Locale locale)
			throws ConversionException {
		if (value == null) {
			return null;
		}

		return getFormat(locale).format(value);
	}

	@Override
	public Number convertToModel(String value,
			Class<? extends Number> targetType, Locale locale)
			throws ConversionException {
		Number n = convertToNumber(value, targetType, locale);
		return n;
	}

	@Override
	protected Number convertToNumber(String value,
			Class<? extends Number> targetType, Locale locale)
			throws ConversionException {
		Number number = super.convertToNumber(value, targetType, locale);
		return number == null ? number
				: convertToResultType(number, resultType);
	}

	protected DecimalFormat getFormat(Locale locale) {
		if (locale == null) {
			locale = Locale.getDefault();
		}
		DecimalFormat decimalFormat = null;
		try {
			decimalFormat = new DecimalFormat(
					StringEscapeUtils.unescapeHtml4(format),
					new DecimalFormatSymbols(locale));
		} catch (IllegalArgumentException e) {
			throw new ConversionException(String.format(
					"formatter %s is invalid for decimal numbers: %s", format,
					e.toString()));
		}

		return decimalFormat;
	}

	@Override
	public Class<Number> getModelType() {
		return Number.class;
	}

	public static Number convertToResultType(final Number number,
			final Class<? extends Number> targetClass) {
		if (Integer.class.isAssignableFrom(targetClass)
				|| Integer.TYPE.isAssignableFrom(targetClass)) {
			return number.intValue();
		} else if (Long.class.isAssignableFrom(targetClass)
				|| Long.TYPE.isAssignableFrom(targetClass)) {
			return number.longValue();
		} else if (Double.class.isAssignableFrom(targetClass)
				|| Double.TYPE.isAssignableFrom(targetClass)) {
			return number.doubleValue();
		} else if (Float.class.isAssignableFrom(targetClass)
				|| Float.TYPE.isAssignableFrom(targetClass)) {
			return number.floatValue();
		} else if (BigDecimal.class.isAssignableFrom(targetClass)) {
			return new BigDecimal(number.doubleValue());
		} else if (BigInteger.class.isAssignableFrom(targetClass)) {
			return new BigInteger(String.valueOf(number.longValue()));
		} else if (Short.class.isAssignableFrom(targetClass)
				|| Short.TYPE.isAssignableFrom(targetClass)) {
			return number.shortValue();
		}
		return number;
	}
}