Java Date Parse convertStringToDate(String dateTime)

Description

Converts a datetime string into and instance of java.util.Date using the date format: yyyy-MM-ddTHH:mm:ss.SSSZ.

License

fedora commons license

Parameter

Parameter	Description
dateTime	A datetime string

Return

Corresponding instance of java.util.Date (returns null if dateTime string argument is empty string or null)

Declaration

public static Date convertStringToDate(String dateTime)

Method Source Code

//package com.java2s;
/* The contents of this file are subject to the license and copyright terms
 * detailed in the license directory at the root of the source tree (also
 * available online at http://fedora-commons.org/license/).
 */// w  w w .  java2 s .c om

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

public class Main {
    /**
     * Converts a datetime string into and instance of java.util.Date using the
     * date format: yyyy-MM-ddTHH:mm:ss.SSSZ.
     *
     * @param dateTime
     *        A datetime string
     * @return Corresponding instance of java.util.Date (returns null if
     *         dateTime string argument is empty string or null)
     */
    public static Date convertStringToDate(String dateTime) {
        return parseDateLoose(dateTime);
    }

    /**
     * Convenience method for {@link #parseDateStrict(String)} which does not
     * throw an exception on error, but merely returns null.
     *
     * @param dateString
     *        the date string to parse
     * @return Date the date, if parse was successful; null otherwise
     */
    public static Date parseDateLoose(String dateString) {
        try {
            return parseDateStrict(dateString);
        } catch (ParseException e) {
            return null;
        }
    }

    /**
     * Attempt to parse the given string of form: yyyy-MM-dd[THH:mm:ss[.SSS][Z]]
     * as a Date.
     *
     * @param dateString the date string to parse
     * @return a Date representation of the dateString
     * @throws ParseException if dateString is null, empty or is otherwise
     * unable to be parsed.
     */
    public static Date parseDateStrict(String dateString) throws ParseException {
        if (dateString == null) {
            throw new ParseException("Argument cannot be null.", 0);
        } else if (dateString.isEmpty()) {
            throw new ParseException("Argument cannot be empty.", 0);
        } else if (dateString.endsWith(".")) {
            throw new ParseException("dateString ends with invalid character.", dateString.length() - 1);
        }
        SimpleDateFormat formatter = new SimpleDateFormat();
        formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
        int length = dateString.length();
        if (dateString.startsWith("-")) {
            length--;
        }
        if (dateString.endsWith("Z")) {
            if (length == 11) {
                formatter.applyPattern("yyyy-MM-dd'Z'");
            } else if (length == 20) {
                formatter.applyPattern("yyyy-MM-dd'T'HH:mm:ss'Z'");
            } else if (length > 21 && length < 24) {
                // right-pad the milliseconds with 0s up to three places
                StringBuilder sb = new StringBuilder(dateString.substring(0, dateString.length() - 1));
                int dotIndex = sb.lastIndexOf(".");
                int endIndex = sb.length() - 1;
                int padding = 3 - (endIndex - dotIndex);
                for (int i = 0; i < padding; i++) {
                    sb.append("0");
                }
                sb.append("Z");
                dateString = sb.toString();
                formatter.applyPattern("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
            } else if (length == 24) {
                formatter.applyPattern("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
            }
        } else {
            if (length == 10) {
                formatter.applyPattern("yyyy-MM-dd");
            } else if (length == 19) {
                formatter.applyPattern("yyyy-MM-dd'T'HH:mm:ss");
            } else if (length > 20 && length < 23) {
                // right-pad millis with 0s
                StringBuilder sb = new StringBuilder(dateString);
                int dotIndex = sb.lastIndexOf(".");
                int endIndex = sb.length() - 1;
                int padding = 3 - (endIndex - dotIndex);
                for (int i = 0; i < padding; i++) {
                    sb.append("0");
                }
                dateString = sb.toString();
                formatter.applyPattern("yyyy-MM-dd'T'HH:mm:ss.SSS");
            } else if (length == 23) {
                formatter.applyPattern("yyyy-MM-dd'T'HH:mm:ss.SSS");
            } else if (dateString.endsWith("GMT") || dateString.endsWith("UTC")) {
                formatter.applyPattern("EEE, dd MMMM yyyyy HH:mm:ss z");
            }
        }
        return formatter.parse(dateString);
    }
}