Java DateTimeFormatter getIndexGroupingPeriod_slow(String date_format)

Description

Utility function to figure out the grouping period based on the index name

License

Apache License

Parameter

Parameter	Description
date_format	a parameter

Return

the date grouping type

Declaration

private static ChronoUnit getIndexGroupingPeriod_slow(String date_format) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Copyright 2015, The IKANOW Open Source Project.
 *
 * 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.//from w w w.  j  a  v a2  s. c  o  m
 *******************************************************************************/

import java.text.SimpleDateFormat;

import java.time.temporal.ChronoUnit;

import java.util.Date;

public class Main {
    /** Utility function to figure out the grouping period based on the index name
     * @param date_format
     * @return the date grouping type
     */
    private static ChronoUnit getIndexGroupingPeriod_slow(String date_format) {

        final SimpleDateFormat d = new SimpleDateFormat(date_format);
        final long try_date_boxes[] = { 3601L, 25L * 3600L,
                8L * 24L * 3600L, 32L * 24L * 3600L, 367L * 34L * 3600L };
        final ChronoUnit ret_date_boxes[] = { ChronoUnit.HOURS,
                ChronoUnit.DAYS, ChronoUnit.WEEKS, ChronoUnit.MONTHS,
                ChronoUnit.YEARS };
        final Date now = new Date();
        final String now_string = d.format(now);
        for (int i = 0; i < try_date_boxes.length; ++i) {
            final String test_str = d.format(new Date(now.getTime() + 1000L
                    * try_date_boxes[i]));
            if (!now_string.equals(test_str)) {
                final String test_str_2 = d.format(new Date(now.getTime()
                        + 2000L * try_date_boxes[i]));
                if (!test_str.equals(test_str_2)) {
                    // Need 2 consecutive indexes to be different, handles eg weeks at month boundaries
                    return ret_date_boxes[i];
                }
            }
        }
        return ChronoUnit.FOREVER;
    }
}

Related

1. getFormatDate(String format)
2. getFormattedDate()
3. getFormattedDateString()
4. getFullFormatter()
5. getGermanFormatter()
6. getLocalizedDateFormat( final Locale LOCALE)
7. getParsedTimeOrNull(String timeText, DateTimeFormatter formatForDisplayTime, DateTimeFormatter formatForMenuTimes, ArrayList formatsForParsing, Locale timePickerLocale)
8. getPreferredDateFormat()
9. getShortDateManualEntryFormatter()