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Determinating if a given string time is in the past, using Java Calendar (Android) [duplicate]

This question already has answers here:
How to compare dates in Java? [duplicate]
(11 answers)
Closed 5 years ago.
I'm trying to write 'isPast(String dateStr)' function, which receives date string and returns true if it's in the past and false otherwise.
private static boolean isPast(String dateStr) {
Calendar c = GregorianCalendar.getInstance();
int currentYear = c.get(Calendar.YEAR);
int currentMonth = c.get(Calendar.MONTH);
int currentDay = c.get(Calendar.DAY_OF_MONTH);
int currentHour = c.get(Calendar.HOUR_OF_DAY);
int currentMinute = c.get(Calendar.MINUTE);
c.set(currentYear, currentMonth, currentDay, currentHour, currentMinute);
Date now = c.getTime();
SimpleDateFormat sdfDates = new SimpleDateFormat("dd/m/yyyy");
Date date = null;
try {
date = sdfDates.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}
if (now.compareTo(date) == 1){
System.out.println(dateStr + " date given is past");
return true;
}
System.out.println(dateStr + " date given is future");
return false;
}
And i'm calling it with:
String str1 = "22/04/2018";
String str2 = "22/01/2018";
System.out.println(isPast(str1));
System.out.println(isPast(str2));
And the output is:
22/04/2018 date given is past
22/01/2018 date given is past
What is going on here? It's not true. I'm on this for too long - it should be simple, obviously i'm missing something with that Calendar object...

Use LocalDate that is available in Java 8
public static void main(String[] args) {
String str1 = "22/04/2018";
String str2 = "22/01/2018";
System.out.println(isPast(str1));
System.out.println(isPast(str2));
}
private static boolean isPast(String dateStr) {
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
LocalDate dates = LocalDate.parse(dateStr, formatter);
return dates.isBefore(LocalDate.now());
}

Try this:
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class Test {
private static final SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
public static void main(String[] args) {
String str1 = "22/04/2018";
String str2 = "22/01/2018";
String str3 = "xx/01/2018";
Date now = new Date();
testDate (str1, now);
testDate (str2, now);
testDate (str3, now);
}
private static void testDate(String str, Date now) {
try {
if (sdf.parse(str).before(now)) {
System.out.println(str + " is in the past.");
} else {
System.out.println(str + " is in the future.");
}
} catch (ParseException e) {
System.out.println("Date not in format dd/MM/yyyy : " + str);
}
}
}
Output:
22/04/2018 is in the future.
22/01/2018 is in the past.
Date not in format dd/MM/yyyy : xx/01/2018
If you have to use Calendar, try this:
private static void testDateUsingCalendar (String str, Date now) {
try {
String[] split = str.split("/");
Calendar c = GregorianCalendar.getInstance();
c.set(Integer.valueOf(split[2]), Integer.valueOf(split[1]), Integer.valueOf(split[0]));
if (c.getTime().before(now)) {
System.out.println(str + " is in the past.");
} else {
System.out.println(str + " is in the future.");
}
} catch (Exception e) {
System.out.println("Date not in format dd/MM/yyyy : " + str);
}
}

Java DateComparison

I use the code below to see if my input date (format mm/dd/yyyy HH:mm:ss) falls within the range of startDate and endDate.
I use compareTo() in this logic. But with the format mm/dd/yyyy, it compares the month alone and prints output in "MYLOGIC methood". But I need the year to be compared to see if the input date is within startDate and endDate range.
public class DateLogicNew {
public static void main(String[] args) {
String startDate[] = new String[1];
String endDate[] = new String[1];
startDate[0] = "01/01/0600 00:00:00";
endDate[0] = "11/27/3337 00:00:00";
String inputArr[] = { "05/01/0500 01:00:00", "11/27/3337 00:00:00",
"05/05/0700 00:00:00", "11/27/2337 00:00:00",
"06/05/4000 00:00:00" };
String protectedArr[] = new String[inputArr.length];
int temp[] = new int[inputArr.length];
System.out.println(inputArr.length);
System.out.println("Length of the inputArr: " + inputArr.length);
// System.out.println("");
for (int i = 0; i < inputArr.length; i++) {
if (inputArr[i]
.matches("^([0-1][0-9])/([0-3][0-9])/([0-9]{4})(?:( [0-2][0-9]):([0-5][0-9]):([0-5][0-9]))?$")) {
System.out.println("Inside if loop");
if (inputArr[i].compareTo(startDate[0]) > 0
&& inputArr[i].compareTo(endDate[0]) < 0) {
System.out.println("inside the compare condition");
temp[i] = 1;
protectedArr[i] = inputArr[i];
System.out
.println("Values of the inputArr in MYLOGIC method : "
+ protectedArr[i]);
}
} else {
temp[i] = 0;
}
}
System.out.println("");
for (int i = 0; i < inputArr.length; i++) {
if (temp[i] == 1) {
inputArr[i] = protectedArr[i];
}
System.out
.println("Final Value to the output port: " + inputArr[i]);
}
}
}

java.time
Parse as date-time objects. Regex is overkill.
The modern approach uses the java.time classes rather than the old legacy date-time classes.
String input = "05/01/0500 01:00:00" ;
DateTimeFormatter f = DateTimeFormatter.ofPattern( "MM/dd/uuuu HH:mm:ss" ) ;
LocalDateTime ldt = LocalDateTime.parse( input , f ) ;
Compare using methods isBefore, isAfter, isEqual.
if( ( ! x.isBefore( start ) ) && x.isBefore( stop ) ) { … }

I myself figured out the solution for my question. Please check the code below to see the logic before comparing the dates.
String startDate = "0600/01/01 00:00:00";
String endDate = "3337/11/27 00:00:00";
try {
for (int i = 0; i < inputArr.length; i++) {
String newDateInput = inputArr[i];
// System.out.println("NewInput:" + newInput);
DateFormat parser = new SimpleDateFormat("MM/dd/yyyy");
DateFormat formatter = new SimpleDateFormat("yyyy/MM/dd");
Date convertedDate = parser.parse(newDateInput);
String newFormattedInput = formatter.format(convertedDate);
// System.out.println("newFormattedInput: " +
// newFormattedInput);
if (newFormattedInput
.matches("^([0-9]{4})/([0-1][0-9])/([0-3][0-9])(?:( [0-2][0-9]):([0-5][0-9]):([0-5][0-9]))?$")) {
if (newFormattedInput.compareTo(startDate) > 0
&& newFormattedInput.compareTo(endDate) < 0) {
temp[i] = 1;
protectedArr[i] = inputArr[i];
System.out
.println("Values of the inputArr in PROTECT method : "
+ protectedArr[i]);
} else {
temp[i] = 0;
}
}
}
} catch (ParseException e) {
e.printStackTrace();
}

How to get first and last date of weeks on basis of month and year in android

how to get first and last date of weeks on basis of month and year in android
ex:we pass month and year (March,2016) then i want all weeks just like
mar5- mar11,(sat to fri)
mar12- mar18,
mar19- mar25,
mar26-april01
please help me

Call this function to get results in a valid week pair list of given month of a year.
ex: getWeekStartEnd("December","2016");
Result: [
December3-December9,
December10-December16,
December17-December23,
December24-December30
]
List<String> getWeekStartEnd (String month , String year) {
List<String> validWeekPairs = new ArrayList<>();
SimpleDateFormat sdf = new SimpleDateFormat("dd-MMMMM-yyyy");
String day = "01";
try {
Date date = sdf.parse(day + "-" + month + "-" + year);
Calendar calendar = Calendar.getInstance();
calendar.clear();
calendar.setTime(date);
calendar.setFirstDayOfWeek(Calendar.SATURDAY);
List<String> startDayOfWeek = new ArrayList<>();
List<String> endDayOfWeek = new ArrayList<>();
int daysInMonth = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
boolean isStartDaySet = false;
boolean hasLastDayOfWeek = true;
for (int currentDay = 01; currentDay <= daysInMonth; currentDay++) {
Date newDate = sdf.parse(currentDay + "-" + month + "-" + year);
calendar.setTime(newDate);
int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);
if (dayOfWeek == Calendar.SATURDAY) {
if (hasLastDayOfWeek) {
startDayOfWeek.add(month + String.valueOf(currentDay));
isStartDaySet = true;
hasLastDayOfWeek = false;
}
} else if (dayOfWeek == Calendar.FRIDAY) {
if (isStartDaySet) {
endDayOfWeek.add(month + String.valueOf(currentDay));
hasLastDayOfWeek = true;
}
}
}
for (int i = 0; i < endDayOfWeek.size(); i++) {
validWeekPairs.add(startDayOfWeek.get(i) + "-" + endDayOfWeek.get(i));
}
return validWeekPairs;
} catch (ParseException e) {
e.printStackTrace();
return validWeekPairs;
}catch (Exception e){
e.printStackTrace();
return validWeekPairs;
}
}

If you are using java.util.Date you can use the method getDay(). It returns Calendar constant, like Calendar.MONDAY.

You can pass the string as 02,2016
List<String> getWeekendsOftheMonth(String monthYearString) {
long monthDate;
List<String> weekEnds = new ArrayList<>();
SimpleDateFormat simpleDateFormat= new SimpleDateFormat("dd,MM,yyyy");
try {
monthYearString="01,".concat(monthYearString);
monthDate = simpleDateFormat.parse(monthYearString).getTime();
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(monthDate);
int maxDate = calendar.getActualMaximum(Calendar.DATE);
int minDate = calendar.getActualMinimum(Calendar.DATE);
for (int i = minDate; i <= maxDate; i++) {
calendar.set(Calendar.DATE, i);
if (calendar.get(Calendar.DAY_OF_WEEK) == Calendar.FRIDAY|| calendar.get(Calendar.DAY_OF_WEEK) == Calendar.SATURDAY) {
weekEnds.add(convertToDate(calendar.getTimeInMillis()));
}
}
}catch (Exception e){
e.printStackTrace();
}
return weekEnds;
}
String convertToDate(Long datetime) {
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd MMM. yyyy");
Date date = new Date(datetime);
return simpleDateFormat.format(date);
}
you can do it from this method.

How to make the format 2015-09-04T11:30:06-0500 to 2015-09-04T11:30:06-05:00 in SimpleDateFormat

Used the below code and not getting the exact output.
Desired output:
2015-09-04T11:30:06-0500 to 2015-09-04T11:30:06-05:00
Actual output:
dateValue => 2015-10-19T16:52:23-0400
a => 2015-10-20T02:22:23+0530
My code:
public class test {
/**
* #param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
String a = formattedDate("2015-10-19T16:52:23-0400");
System.out.println ("a => " + a);
}
public static String formattedDate (String dateValue) {
String expectedFormat = "";
SimpleDateFormat inputDateFormat =
new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
SimpleDateFormat outputDateFormat =
new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZ");
try {
System.out.println("dateValue => " + dateValue);
if (dateValue == null || dateValue.isEmpty()) {
dateValue = "";
}
inputDateFormat.setLenient(true);
Date d = inputDateFormat.parse(dateValue);
expectedFormat = outputDateFormat.format(d);
} catch (Exception e) {
// Sending back the current datetime in the desired format
Calendar cal = Calendar.getInstance();
expectedFormat = outputDateFormat.format(cal.getTime());
}
return expectedFormat;
}
}

Under Java 7 and higher, you can use XXX to output the time zone with a column:
SimpleDateFormat outputDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX");
When you use this to format a data, it will return for example:
2001-07-04T12:08:56-07:00
See the documentation for more examples.

Since I'm using 1.6, XXX is not supported. So used alternative way to achieve this. This is what I did for alternative way..
public static String formattedDate (String dateValue) {
StringBuilder expectedFormat;
SimpleDateFormat inputDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
try {
if (dateValue == null || dateValue.isEmpty()) {
dateValue = "";
}
inputDateFormat.setLenient(false);
Date d = inputDateFormat.parse(dateValue);
} catch (Exception e) {
System.out.println("Error in parsing : " + e.getMessage());
// Sending back the current datetime in the desired format
Calendar cal = Calendar.getInstance();
dateValue = inputDateFormat.format(cal.getTime());
} finally {
expectedFormat = new StringBuilder(dateValue).insert(dateValue.length()-2, ":");
}
return expectedFormat.toString();
}

When you need only the third last character changed and give a string as a parameter how about leaving it a String?
public static String formattedDate (String dateValue)
{
return dateValue.substring(0, dateValue.length() - 2)
+ ":"
+ dateValue.substring(dateValue.length() - 2);
}
Output:
a => 2015-10-19T16:52:23-04:00

Android week View how can we Get all days of a next and previous week

I'm able to get current week dates, But How to list previous / next week days ?
This is the method
public String [] getWeekDay()
{
Calendar now = Calendar.getInstance();
SimpleDateFormat format = new SimpleDateFormat("dd");
String [] days = new String[7];
int delta = -now.get(GregorianCalendar.DAY_OF_WEEK) + 1;
now.add(Calendar.DAY_OF_MONTH , delta);
for (int i = 0; i < 7; i++)
{
days [i] = format.format(now.getTime());
now.add(Calendar.DAY_OF_MONTH , 1);
}
// System.out.println(Arrays.toString(days));
return days;
}
pls see the image, and tell me how to get the next and previous week days

finally i got the answer pls see this
Get the present Week:
public String [] getWeekDay()
{
Calendar now = Calendar.getInstance();
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String [] days = new String[7];
int delta = -now.get(GregorianCalendar.DAY_OF_WEEK) + 1;
now.add(Calendar.DAY_OF_MONTH , delta);
for (int i = 0; i < 7; i++)
{
days [i] = format.format(now.getTime());
now.add(Calendar.DAY_OF_MONTH , 1);
}
return days;
}
Get the Next Week:
int weekDaysCount=0;
public String [] getWeekDayNext()
{
weekDaysCount++;
Calendar now1 = Calendar.getInstance();
Calendar now = (Calendar) now1.clone();
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String [] days = new String[7];
int delta = -now.get(GregorianCalendar.DAY_OF_WEEK) + 1;
now.add(Calendar.WEEK_OF_YEAR , weekDaysCount);
now.add(Calendar.DAY_OF_MONTH , delta);
for (int i = 0; i < 7; i++)
{
days [i] = format.format(now.getTime());
now.add(Calendar.DAY_OF_MONTH , 1);
}
return days;
}
Get the previous Week:
public String [] getWeekDayPrev()
{
weekDaysCount--;
Calendar now1 = Calendar.getInstance();
Calendar now = (Calendar) now1.clone();
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String [] days = new String[7];
int delta = -now.get(GregorianCalendar.DAY_OF_WEEK) + 1;
now.add(Calendar.WEEK_OF_YEAR , weekDaysCount);
now.add(Calendar.DAY_OF_MONTH , delta);
for (int i = 0; i < 7; i++)
{
days [i] = format.format(now.getTime());
now.add(Calendar.DAY_OF_MONTH , 1);
}
return days;
}
to assign the textView
NextPreWeekday = getWeekDay();
firstDayOfWeek = CommonMethod.convertWeekDays(NextPreWeekday [0]);
lastDayOfWeek = CommonMethod.convertWeekDays(NextPreWeekday [6]);
textViewDate.setText(firstDayOfWeek + "-" + lastDayOfWeek + " " + CommonMethod.convertWeekDaysMouth(NextPreWeekday [6]));
textViewSun.setText(CommonMethod.convertWeekDays(NextPreWeekday [0]) + "\nSun");
textViewMon.setText(CommonMethod.convertWeekDays(NextPreWeekday [1]) + "\nMon");
textViewTue.setText(CommonMethod.convertWeekDays(NextPreWeekday [2]) + "\nTue");
textViewWed.setText(CommonMethod.convertWeekDays(NextPreWeekday [3]) + "\nWeb");
textViewThu.setText(CommonMethod.convertWeekDays(NextPreWeekday [4]) + "\nThu");
textViewFri.setText(CommonMethod.convertWeekDays(NextPreWeekday [5]) + "\nFri");
textViewSat.setText(CommonMethod.convertWeekDays(NextPreWeekday [6]) + "\nSat");
public static String convertWeekDays(String date)
{
String formattedDate = null;
try
{
SimpleDateFormat originalFormat = new SimpleDateFormat("yyyy-MM-dd" , Locale.ENGLISH);
SimpleDateFormat targetFormat = new SimpleDateFormat("dd");
Date date12 = originalFormat.parse(date);
formattedDate = targetFormat.format(date12);
} catch (Exception e)
{
e.printStackTrace();
}
return formattedDate;
}
public static String convertWeekDaysMouth(String date)
{
String formattedDate = null;
try
{
SimpleDateFormat originalFormat = new SimpleDateFormat("yyyy-MM-dd" , Locale.ENGLISH);
SimpleDateFormat targetFormat = new SimpleDateFormat("MMM yyyy");
Date date12 = originalFormat.parse(date);
formattedDate = targetFormat.format(date12);
} catch (Exception e)
{
e.printStackTrace();
}
return formattedDate;
}

For current week.
SimpleDateFormat displayDate = new SimpleDateFormat("dd-MMM-yyyyy"));
final Calendar calenderThisWeek = Calendar.getInstance();
calenderThisWeek.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
String strWek = displayDate.format(calenderThisWeek.getTime()); // dd-mmm-yyyy
calenderThisWeek.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
String endWek = displayDate.format(calenderThisWeek.getTime()); // dd-mmm-yyyy
For Previous Week
final Calendar calenderpreviousWeek = Calendar.getInstance();
calenderpreviousWeek.add(Calendar.DAY_OF_WEEK, -1);
calenderpreviousWeek.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
String strWek = displayDate.format(calenderThisWeek.getTime()); // dd-mmm-yyyy
calenderpreviousWeek.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
String endWek = displayDate.format(calenderpreviousWeek.getTime()); // dd-mmm-yyyy
For Next Week
final Calendar calenderNextWeek = Calendar.getInstance();
calenderNextWeek.add(Calendar.DAY_OF_WEEK, +1);
calenderNextWeek.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
String strWek = displayDate.format(calenderNextWeek.getTime()); // dd-mmm-yyyy
calenderNextWeek.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
String endWek = displayDate.format(calenderNextWeek.getTime()); // dd-mmm-yyyy