jidefx.utils.converter.PercentConverter Maven / Gradle / Ivy
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/*
* @(#)PercentConverter.java 5/19/2013
*
* Copyright 2002 - 2013 JIDE Software Inc. All rights reserved.
*/
package jidefx.utils.converter;
import java.text.NumberFormat;
import java.util.Locale;
/**
* {@link ObjectConverter} implementation for a percentage
*/
public class PercentConverter extends DoubleConverter {
public static final ConverterContext CONTEXT = new ConverterContext("Percent"); //NON-NLS
public PercentConverter() {
this(NumberFormat.getPercentInstance());
}
public PercentConverter(Locale locale) {
this(NumberFormat.getPercentInstance(locale));
}
public PercentConverter(NumberFormat format) {
super(format);
}
/**
* Converts the String to a Double. It will use the NumberFormat defined as {@link #PROPERTY_NUMBER_FORMAT} if any.
* If not there, it will use {@link #getNumberFormat()} to get the NumberFormat to do the conversion.
*
* Different from a DoubleConverter, if the String doesn't have a percentage sign at the end, we will divide the
* number from DoubleConverter by 100 and return the value. That's because "50%" actually is 0.5. If user forgot to
* include a % sign, for example, pass in "50", we should still treat it as percentage and return 0.5 as they are
* using a PercentConverter.
*
* Please note, the conversion may involve rounding or truncation.
*
* @param string the string to be converted.
* @param context the context
* @return the Number converted from the String.
*/
@Override
public Double fromString(String string, ConverterContext context) {
Number number = numberFromString(string, context);
if (number == null) {
number = Double.parseDouble(string);
}
if (string != null && !string.trim().endsWith("%") && number != null) {
number = number.doubleValue() / 100;
}
return number != null ? number.doubleValue() : null;
}
}