Split DateTime into Combination of String and Date in Java

Question

I hit API that will return date in datetime type. The example of the return is "1994-12-03T12:00:00" and I want to modify the return become "Pca19941203". The return will be apply in csv file. I do the modification in Java. Is there some ways to do that ?

Answer 1

Java 8+ (Recommended):

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

LocalDateTime.parse("1994-12-03T12:00:00")
             .format(DateTimeFormatter.ofPattern("'Pca'uuuuMMdd"))

Joda-Time:

import org.joda.time.LocalDateTime;
import org.joda.time.format.DateTimeFormat;

LocalDateTime.parse("1994-12-03T12:00:00")
             .toString(DateTimeFormat.forPattern("'Pca'yyyyMMdd"))

Old Java API:

import java.text.SimpleDateFormat;

new SimpleDateFormat("'Pca'yyyyMMdd").format(new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss")
                                     .parse("1994-12-03T12:00:00"))

Output (from all 3)

Pca19941203

Answer 2

You can to do the next

/*
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 * and open the template in the editor.
 */
package javaapplication2;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class as {

    public static void main(String[] args) {
        Long tmp = castDateToString(new Date());

        System.out.println(tmp);
        //Devolver al servicio
        System.out.println(returnServiceFormat(tmp, "yyyy/MM/dd"));
    }

    public static long castDateToString(Date system) {
        return system.getTime();
    }

    public static String returnServiceFormat(long date, String format) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTimeInMillis(date);
        DateFormat df = new SimpleDateFormat(format);
        return String.valueOf(df.format(calendar.getTime()));
    }
}

The result was

run: 1579226334699 2020/01/16 BUILD SUCCESSFUL (total time: 0 seconds)