com.cedarsoftware.util.DateUtilities Maven / Gradle / Ivy
package com.cedarsoftware.util;
import java.util.Calendar;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Handy utilities for working with Java Dates.
*
* @author John DeRegnaucourt ([email protected])
*
* Copyright (c) Cedar Software LLC
*
* 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.
*/
public class DateUtilities
{
private static final String mos = "(Jan|January|Feb|February|Mar|March|Apr|April|May|Jun|June|Jul|July|Aug|August|Sep|Sept|September|Oct|October|Nov|November|Dec|December)";
private static final Pattern datePattern1 = Pattern.compile("(\\d{4})[\\./-](\\d{1,2})[\\./-](\\d{1,2})");
private static final Pattern datePattern2 = Pattern.compile("(\\d{1,2})[\\./-](\\d{1,2})[\\./-](\\d{4})");
private static final Pattern datePattern3 = Pattern.compile(mos + "[ ,]+(\\d{1,2})[ ,]+(\\d{4})", Pattern.CASE_INSENSITIVE);
private static final Pattern datePattern4 = Pattern.compile("(\\d{1,2})[ ,]" + mos + "[ ,]+(\\d{4})", Pattern.CASE_INSENSITIVE);
private static final Pattern datePattern5 = Pattern.compile("(\\d{4})[ ,]" + mos + "[ ,]+(\\d{1,2})", Pattern.CASE_INSENSITIVE);
private static final Pattern timePattern1 = Pattern.compile("(\\d{2})[:\\.](\\d{2})[:\\.](\\d{2})[\\.](\\d{1,3})");
private static final Pattern timePattern2 = Pattern.compile("(\\d{2})[:\\.](\\d{2})[:\\.](\\d{2})");
private static final Pattern timePattern3 = Pattern.compile("(\\d{2})[:\\.](\\d{2})");
private static final Map months = new LinkedHashMap();
static
{
// Month name to number map
months.put("jan", "1");
months.put("january", "1");
months.put("feb", "2");
months.put("february", "2");
months.put("mar", "3");
months.put("march", "3");
months.put("apr", "4");
months.put("april", "4");
months.put("may", "5");
months.put("jun", "6");
months.put("june", "6");
months.put("jul", "7");
months.put("july", "7");
months.put("aug", "8");
months.put("august", "8");
months.put("sep", "9");
months.put("sept", "9");
months.put("september", "9");
months.put("oct", "10");
months.put("october", "10");
months.put("nov", "11");
months.put("november", "11");
months.put("dec", "12");
months.put("december", "12");
}
public static Date parseDate(String dateStr)
{
if (dateStr == null)
{
return null;
}
dateStr = dateStr.trim();
if ("".equals(dateStr))
{
return null;
}
// Determine which date pattern (Matcher) to use
Matcher matcher = datePattern1.matcher(dateStr);
String year, month = null, day, mon = null;
if (matcher.find())
{
year = matcher.group(1);
month = matcher.group(2);
day = matcher.group(3);
}
else
{
matcher = datePattern2.matcher(dateStr);
if (matcher.find())
{
month = matcher.group(1);
day = matcher.group(2);
year = matcher.group(3);
}
else
{
matcher = datePattern3.matcher(dateStr);
if (matcher.find())
{
mon = matcher.group(1);
day = matcher.group(2);
year = matcher.group(3);
}
else
{
matcher = datePattern4.matcher(dateStr);
if (matcher.find())
{
day = matcher.group(1);
mon = matcher.group(2);
year = matcher.group(3);
}
else
{
matcher = datePattern5.matcher(dateStr);
if (!matcher.find())
{
error("Unable to parse: " + dateStr);
}
year = matcher.group(1);
mon = matcher.group(2);
day = matcher.group(3);
}
}
}
}
if (mon != null)
{ // Month will always be in Map, because regex forces this.
month = months.get(mon.trim().toLowerCase());
}
// Determine which date pattern (Matcher) to use
matcher = timePattern1.matcher(dateStr);
if (!matcher.find())
{
matcher = timePattern2.matcher(dateStr);
if (!matcher.find())
{
matcher = timePattern3.matcher(dateStr);
if (!matcher.find())
{
matcher = null;
}
}
}
Calendar c = Calendar.getInstance();
c.clear();
// Regex prevents these from ever failing to parse
int y = Integer.parseInt(year);
int m = Integer.parseInt(month) - 1; // months are 0-based
int d = Integer.parseInt(day);
if (m < 0 || m > 11)
{
error("Month must be between 1 and 12, date: " + dateStr);
}
if (d < 0 || d > 31)
{
error("Day cannot be > 31, date: " + dateStr);
}
if (matcher == null)
{ // no [valid] time portion
c.set(y, m, d);
}
else
{
String hour = matcher.group(1);
String min = matcher.group(2);
String sec = "00";
String milli = "000";
if (matcher.groupCount() > 2)
{
sec = matcher.group(3);
}
if (matcher.groupCount() > 3)
{
milli = matcher.group(4);
}
// Regex prevents these from ever failing to parse.
int h = Integer.parseInt(hour);
int mn = Integer.parseInt(min);
int s = Integer.parseInt(sec);
int ms = Integer.parseInt(milli);
if (h < 0 || h > 23)
{
error("Hour must be between 0 and 23, time: " + dateStr);
}
if (mn < 0 || mn > 59)
{
error("Minute must be between 0 and 59, time: " + dateStr);
}
if (s < 0 || s > 59)
{
error("Second must be between 0 and 59, time: " + dateStr);
}
// regex enforces millis to 000 to 999 or none
c.set(y, m, d, h, mn, s);
c.set(Calendar.MILLISECOND, ms);
}
return c.getTime();
}
private static void error(String msg)
{
throw new IllegalArgumentException(msg);
}
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