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

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.tools.dataTypes.impl.coercion;

import java.math.BigDecimal;

import java.sql.Time;

import java.text.NumberFormat;

import java.util.Date;

import java.util.Locale;

import java.text.DateFormat;

import java.text.DecimalFormatSymbols;

import org.gvsig.tools.dataTypes.AbstractCoercion;

import org.gvsig.tools.dataTypes.Coercion;

import org.gvsig.tools.dataTypes.CoercionContext;

import org.gvsig.tools.dataTypes.CoercionContextLocale;

import org.gvsig.tools.dataTypes.CoercionException;

import org.gvsig.tools.dataTypes.DataTypeUtils;

public class CoerceToString extends AbstractCoercion {

    @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);

    }

}