Java Date Convert convertStringToDate(String string)

Description

Convert data of the form "MM-DD-YY HH:mm" to Date

License

Open Source License

Parameter

Parameter	Description
string	a parameter

Return

Date or null

Declaration

public static final Date convertStringToDate(String string) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * This file is part of zdt2go.//ww  w .  j a v  a  2s  . c  om
 * Copyright (c) 2009 Achim Weimert.
 * http://code.google.com/p/zdt2go/
 * 
 * zdt2go 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 3 of the License, or
 * (at your option) any later version.
 * 
 * zdt2go 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 zdt2go.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * Contributors:
 *     Achim Weimert - initial API and implementation
 ******************************************************************************/

import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class Main {
    private static final int MONTH = 0;
    private static final int DAY = 1;
    private static final int YEAR = 2;
    private static final int HOUR = 3;
    private static final int MINUTE = 4;
    private static final String seperator[] = { "-", "-", " ", ":" };

    /**
     * Convert data of the form "MM-DD-YY HH:mm" to Date
     * @param string
     * @return Date or null
     */
    public static final Date convertStringToDate(String string) {
        if (string == null) {
            return null;
        }

        // split string into parts
        String[] parts = splitStringIntoParts(string);
        if (parts == null) {
            return null;
        }

        // validation
        boolean result = validateDateParts(parts);
        if (!result) {
            return null;
        }

        // create data
        Calendar calendar = createCalendarFromParts(parts);

        return calendar.getTime();
    }

    private static String[] splitStringIntoParts(String string) {
        String parts[] = new String[seperator.length + 1];
        int pos, startPos;

        // split string into parts
        startPos = 0;
        int i;
        try {
            for (i = 0; i < seperator.length; i++) {
                pos = string.indexOf(seperator[i], startPos);
                if (pos < 0) {
                    return null;
                }
                parts[i] = string.substring(startPos, pos);
                parts[i] = parts[i].trim();
                startPos = pos + 1;
            }
            parts[i] = string.substring(startPos);
        } catch (IndexOutOfBoundsException e) {
            return null;
        }
        return parts;
    }

    private static boolean validateDateParts(String[] parts) {
        // make sure all parts are numbers
        for (int j = 0; j < parts.length; j++) {
            try {
                int number = Integer.parseInt(parts[j]);
                if (number < 0) {
                    return false;
                }
            } catch (NumberFormatException e) {
                return false;
            }
        }
        // check year
        if (parts[YEAR].length() != 2 && parts[YEAR].length() != 4) {
            return false;
        }
        if (parts[YEAR].length() == 2) {
            // move year into the right century
            if (Integer.parseInt(parts[YEAR]) >= 50) {
                parts[YEAR] = "19" + parts[YEAR];
            } else {
                parts[YEAR] = "20" + parts[YEAR];
            }
        }
        // check month
        if (parts[MONTH].length() != 1 && parts[MONTH].length() != 2) {
            return false;
        }
        if (Integer.parseInt(parts[MONTH]) > 12) {
            return false;
        }
        // check day
        if (parts[DAY].length() != 1 && parts[DAY].length() != 2) {
            return false;
        }
        if (Integer.parseInt(parts[DAY]) > 31) {
            return false;
        }
        // check hour
        if (parts[HOUR].length() != 1 && parts[HOUR].length() != 2) {
            return false;
        }
        if (Integer.parseInt(parts[HOUR]) > 23) {
            return false;
        }
        // check minute
        if (parts[MINUTE].length() != 1 && parts[MINUTE].length() != 2) {
            return false;
        }
        if (Integer.parseInt(parts[MINUTE]) > 59) {
            return false;
        }

        return true;
    }

    private static Calendar createCalendarFromParts(String[] parts) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTimeZone(TimeZone.getDefault());
        calendar.set(Calendar.YEAR, Integer.parseInt(parts[YEAR]));
        calendar.set(Calendar.MONTH, Integer.parseInt(parts[MONTH]) - 1);
        calendar.set(Calendar.DAY_OF_MONTH, Integer.parseInt(parts[DAY]));
        calendar.set(Calendar.HOUR_OF_DAY, Integer.parseInt(parts[HOUR]));
        calendar.set(Calendar.MINUTE, Integer.parseInt(parts[MINUTE]));
        calendar.set(Calendar.SECOND, 0);
        calendar.set(Calendar.MILLISECOND, 0);
        return calendar;
    }
}

Related

1. convertLocalToTimezone(Date original, String targetTimezoneId)
2. convertsDateToGMTTimezone(Date date)
3. convertSistemDependentDateToDesiredTimeZone(final Date sistemDependentDate, TimeZone desiredTimeZone)
4. convertStringToDate(String date)
5. convertStringToDate(String date)
6. convertToClientTime(Date serverDate, Integer clientTimezoneOffset)
7. convertToDate(String source)
8. convertToDateStamp(long time)
9. convertToDateTime(String source)