org.gbif.ipt.struts2.converter.CoordinateFormatConverter.java Source code

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Here is the source code for org.gbif.ipt.struts2.converter.CoordinateFormatConverter.java

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/***************************************************************************
 * Copyright 2011 Global Biodiversity Information Facility Secretariat
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 ***************************************************************************/
package org.gbif.ipt.struts2.converter;

import org.gbif.ipt.utils.CoordinateUtils;

import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.text.ParseException;
import java.util.Map;

import com.opensymphony.xwork2.conversion.TypeConversionException;
import org.apache.commons.lang3.Range;
import org.apache.struts2.util.StrutsTypeConverter;

/**
 * This class provides the method to validate the latitude and longitude coordinates as decimal numbers.
 */
public abstract class CoordinateFormatConverter extends StrutsTypeConverter {

    private static final String ANGLE = "coordinate.angle";
    private static final char ALTERNATIVE_DECIMAL_SEPARATOR = ',';
    private static final String DECIMAL_PATTERN = "###.##";

    @Override
    public Object convertFromString(Map context, String[] values, Class toClass) {
        // The null value is needed to validate in EmlValidator.java class
        if (values[0].length() == 0) {
            return null;
        }
        // The full name of the property which call the method contained in the Map context
        Object coordObject = context.get(ANGLE);
        // The latitude is validating in a range of doubles
        // validate coordinates in case the action context doesn't work properly.
        if (coordObject == null) {
            throw new TypeConversionException("Invalid decimal number: " + values[0]);
        } else {
            String coordinate = context.get(ANGLE).toString();
            // Assign the values of the range depending the property who calls the method.
            Range<Double> range;
            if (coordinate.equals(CoordinateUtils.LATITUDE)) {
                // The range of the latitude coordinate. (-90,90)
                range = Range.between(CoordinateUtils.MIN_LATITUDE, CoordinateUtils.MAX_LATITUDE);
            } else {
                // The range of the longitude coordinate. (-180,180)
                range = Range.between(CoordinateUtils.MIN_LONGITUDE, CoordinateUtils.MAX_LONGITUDE);
            }

            Double number;
            try {
                // Converts String to double if fails throws a NumberFormatException.
                // If the String contains a comma, a character, it throws the exception.
                number = Double.parseDouble(values[0]);
                // If the value is in the range, returns the double.
                if (range.contains(number)) {
                    return number;
                } else {
                    throw new TypeConversionException("Invalid decimal number: " + values[0]);
                }
            } catch (NumberFormatException e) {
                // Creating a pattern which will convert the comma to period
                // It will return a ParseException if the format was wrong.
                DecimalFormatSymbols symbols = new DecimalFormatSymbols();
                symbols.setDecimalSeparator(ALTERNATIVE_DECIMAL_SEPARATOR);
                DecimalFormat decimal = new DecimalFormat(DECIMAL_PATTERN, symbols);
                try {
                    number = decimal.parse(values[0]).doubleValue();
                    if (range.contains(number)) {
                        return number;
                    } else {
                        throw new TypeConversionException("Invalid decimal number: " + values[0]);
                    }
                } catch (ParseException e1) {
                    throw new TypeConversionException("Invalid decimal number: " + values[0]);
                }
            }
        }
    }

    @Override
    public String convertToString(Map context, Object o) {
        if (o instanceof Double) {
            return o.toString();
        } else {
            throw new TypeConversionException("Invalid decimal number: " + o.toString());
        }
    }

}