Application: gvSIG desktop » Library: org.gvsig.tools

import java.text.DecimalFormatSymbols;

    @Override

    public Object coerce(Object value) throws CoercionException {

        if (value == null) {

            return null;

        }

        if (value instanceof CharSequence) {

            return value.toString();

        }

        if (value instanceof Number) {

            return coerce(value, DataTypeUtils.coerceContextDefaultDecimal());

        }

        return coerce(value, DataTypeUtils.coerceContextDefaultLocale());

    @Override

    public Object coerce(Object value, CoercionContext context) throws CoercionException {

        if (value == null) {

            return null;

        if (value instanceof CharSequence) {

            return value.toString();

        }

        if (value instanceof CharSequence) {

            return value.toString();

        }

        if (context == null) {

            if (value instanceof Number) {

                context = DataTypeUtils.coerceContextDefaultDecimal();

            } else {

                context = DataTypeUtils.coerceContextDefaultLocale();

            }

        }

        try {

            Locale locale;

            if (context instanceof CoercionContextLocale) {

                locale = ((CoercionContextLocale) context).locale();

            } else {

                locale = Locale.getDefault();

            }

            String s;

            if (value instanceof Time) {

                DateFormat df = DateFormat.getTimeInstance(DateFormat.LONG, locale);

                s = df.format(value);

            } else if (value instanceof Date) {

                DateFormat df = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.LONG, locale);

                s = df.format(value);

            } else if (value instanceof Float || value instanceof Double) {

                double d = (double) value;

                NumberFormat nf = NumberFormat.getInstance(locale);

                if (d > 1.8014398509481984E16 || d < -1.8014398509481984E16) {

                    // Esto viene a ser la maxima precision de la mantisa, Math.pow(2, 54), 

                    // asi que para valores mas grandes utilizamos la notacion cientifica.

                    s = String.format("%E", d);

                } else {

                    nf.setMaximumFractionDigits(16);

                    nf.setGroupingUsed(false);

                    s = nf.format(((Number) value).doubleValue());

                }

            } else if (value instanceof BigDecimal) {

                DecimalFormatSymbols dfs = new DecimalFormatSymbols(locale);

                char decimalSeparator = dfs.getDecimalSeparator();

                s = ((BigDecimal) value).toPlainString();

                if (decimalSeparator!='.'){

                    s = s.replace('.', decimalSeparator);

                }

            } else if (value instanceof Locale) {

                s = CoerceToLocale.toString((Locale) value);

            } else {

                s = value.toString();

            }

            return s;

        } catch (Exception e) {

            throw new CoercionException(e);

        }

    }

    public static void main(String[] args) throws CoercionException {

        Coercion toString = new CoerceToString();

        String x = (String) toString.coerce(10.5);

        System.out.println(x);

        x = (String) toString.coerce((double) 0.168873933773767);

        System.out.println(x);

        x = (String) toString.coerce((double) 123456789012345678901234567890d);

        System.out.println(x);

        x = (String) toString.coerce((double) -123456789012345678901234567890d);

        System.out.println(x);

    }