DateValidator.java

/*
   Copyright (C) 2005-2012, by the President and Fellows of Harvard College.

   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.

   Dataverse Network - A web application to share, preserve and analyze research data.
   Developed at the Institute for Quantitative Social Science, Harvard University.
   Version 3.0.
*/
/*
 * DateValidator.java
 *
 * Created on February 23, 2007, 3:37 PM
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */
package edu.harvard.iq.dvn.core.web.util;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import javax.faces.application.FacesMessage;
import javax.faces.component.UIComponent;
import javax.faces.component.UIInput;
import javax.faces.context.FacesContext;
import javax.faces.validator.Validator;

/**
 *
 * @author ekraffmiller
 */
public class DateValidator implements Validator, java.io.Serializable  {
    
    /** Creates a new instance of DateValidator */
    public DateValidator() {
    }
    
    public void validate(FacesContext context,
            UIComponent toValidate,
            Object value) {
        String dateString = ((String) value).trim();
        boolean valid = validate(dateString);
        if (!valid) {
            ((UIInput)toValidate).setValid(false);
            
            FacesMessage message = new FacesMessage("Invalid Date Format.  Valid formats are YYYY-MM-DD, YYYY-MM, or YYYY. Optionally, 'BC' can be appended to the year. (By default, AD is assumed.)");
            context.addMessage(toValidate.getClientId(context), message);
        }
        
    }
    
    private boolean validate(String dateString) {
        boolean valid=false;
        
        valid = isValid(dateString,"yyyy-MM-dd");
        if (!valid ) {
            valid = isValid(dateString, "yyyy-MM");
        }     
        if (!valid) {
            valid = isValid(dateString,"yyyy");
        }
        if (!valid ) {
            valid = isValid(dateString, "yyyyyyyyy-MM-dd GG");
        }   
        if (!valid ) {
            valid = isValid(dateString, "yyyyyyyyy-MM GG");
        }     
        if (!valid) {
            valid = isValid(dateString,"yyyyyyyyy GG");
        }      
        return valid;
    }
    
    private boolean isValid(String dateString, String pattern) {
        boolean valid=true;
        Date date;
        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
        sdf.setLenient(false);
        try {
            dateString = dateString.trim();
            date = sdf.parse(dateString);
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(date);
            int year = calendar.get(Calendar.YEAR);
            int era = calendar.get(Calendar.ERA);
            if (era == GregorianCalendar.AD ) {
                if ( year > 9999) {
                    valid=false;
                }

            }
         //   System.out.println("pattern is "+ pattern);
         //   System.out.println("Year is "+year);
         //   System.out.println("Calendar date is "+date.toString());
         //   System.out.println("Era is "+calendar.get(Calendar.ERA));
        }catch (ParseException e) {
            valid=false;
        }
        if (dateString.length()>pattern.length()) {
            valid=false;
        }
        return valid;
    }
    public static void main(String args[]) {
        DateValidator validator = new DateValidator();     
        System.out.println("Result is "+validator.validate("-20080-02 "));
        
    }
}