How can I get start date and end date of a given month like Apr 22 in java android?-CodePudding

How can I get start date and end date of a given month. But here the month is coming in the format of 'Apr 22' . So I need to get the start date and end date of April 2022.

How can I get this in java? The format I am looking is ddMMyyyy.

CodePudding user response：

You can use the YearMonth class from the java.time api to parse your input and get the first and last day of month as LocalDate:

import java.time.LocalDate;
import java.time.YearMonth;
import java.time.format.DateTimeFormatter;

....

String input = "Apr 22";
DateTimeFormatter ymFormater = DateTimeFormatter.ofPattern("MMM uu");
DateTimeFormatter dtFormater = DateTimeFormatter.ofPattern("ddMMuuuu");

LocalDate startOfMonth = YearMonth.parse(input, ymFormater).atDay(1);
LocalDate endOfMonth   = YearMonth.parse(input, ymFormater).atEndOfMonth();

System.out.println(startOfMonth.format(dtFormater));
System.out.println(endOfMonth.format(dtFormater));

CodePudding user response：

You can use SimpleDateFormat & Calendar to get desired result like below:

private void getFirstAndLastDate() {
    String input = "Apr 22";

    // Create two date format
    //One to read the date from the input string, the other to string the date
    SimpleDateFormat formats = new SimpleDateFormat("MMM yy", Locale.US);
    SimpleDateFormat newFormat = new SimpleDateFormat("ddMMyyyy", Locale.US);
    
    String firstDate, lastDate;

    try {
        Date date = formats.parse(input);
        Calendar myCalendar = Calendar.getInstance();
        myCalendar.setTime(date);

        // Just set the day to 1
        myCalendar.set(Calendar.DAY_OF_MONTH, 1);
        firstDate = newFormat.format(myCalendar.getTime());

        // Add a month
        // add day -1
        myCalendar.add(Calendar.MONTH, 1);
        myCalendar.add(Calendar.DAY_OF_MONTH, -1);
        lastDate = newFormat.format(myCalendar.getTime());

        Log.e("firstDate: ", firstDate);
        Log.e("lastDate: ", lastDate);

    } catch (ParseException e) {
        e.printStackTrace();
    }
}

It may not be the best way, but thus wanted results can be obtained.