Code to Convert dd-MMM-yy to dd-MM-yyyy in Android Java

Code to Convert dd-MMM-yy `to` dd-MM-yyyy in Android Java

To convert workDate for example from format "15-JUL-25" to "15-07-2025" in Java, you can use SimpleDateFormat as shown below:

Method 1

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

…

String originalFormat = “dd-MMM-yy”; // Input format: 15-JUL-25
String targetFormat = “dd-MM-yyyy”; // Output format: 15–07–2025

SimpleDateFormat inputFormat = new SimpleDateFormat(originalFormat, Locale.ENGLISH);
SimpleDateFormat outputFormat = new SimpleDateFormat(targetFormat, Locale.ENGLISH);

try {
Date date = inputFormat.parse(workDate); // workDate = “15-JUL-25”
String formattedDate = outputFormat.format(date); // formattedDate = “15–07–2025”

jsonObject.put(“workDt”, formattedDate); // ✅ Put formatted date in JSON
} catch (ParseException e) {
e.printStackTrace();
jsonObject.put(“workDt”, workDate); // Fallback to original if parsing fails
}

Explanation:

"dd-MMM-yy" parses input like "15-JUL-25" (case-insensitive with Locale.ENGLISH)
"dd-MM-yyyy" formats output like "15-07-2025"
Safe fallback is added in case parsing fails

Method 2

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;

public class DateConverter {

public static String convertDateFormat(String dateString) {
// Input format: dd-MMM-yy (e.g., 15-Jul-25)
SimpleDateFormat inputFormat = new SimpleDateFormat(“dd-MMM-yy”, Locale.ENGLISH);

// Output format: dd-MM-yyyy (e.g., 15–07–2025)
SimpleDateFormat outputFormat = new SimpleDateFormat(“dd-MM-yyyy”, Locale.getDefault());

try {
// Parse the input date string into a Date object
Date date = inputFormat.parse(dateString);

// Format the Date object into the desired output format
return outputFormat.format(date);
} catch (ParseException e) {
e.printStackTrace();
// Handle parsing error, e.g., return null or throw an exception
return null;
}
}

public static void main(String[] args) {
// Example usage:
String dateToConvert = “15-Jul-25”; // Current year is 2025
String convertedDate = convertDateFormat(dateToConvert);

if (convertedDate != null) {
System.out.println(“Original Date: “ + dateToConvert);
System.out.println(“Converted Date: “ + convertedDate);
} else {
System.out.println(“Date conversion failed.”);
}

String anotherDate = “01-Jan-01”; // Test with year 2001
String convertedAnotherDate = convertDateFormat(anotherDate);
if (convertedAnotherDate != null) {
System.out.println(“Original Date: “ + anotherDate);
System.out.println(“Converted Date: “ + convertedAnotherDate);
} else {
System.out.println(“Date conversion failed.”);
}
}
}

You can convert a date string from “dd-MMM-yy” to “dd-MM-yyyy” in Android Java using SimpleDateFormat. Here's the code:

Java

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;

public class DateConverter {

    public static String convertDateFormat(String dateString) {
        // Input format: dd-MMM-yy (e.g., 15-Jul-25)
        SimpleDateFormat inputFormat = new SimpleDateFormat("dd-MMM-yy", Locale.ENGLISH);

        // Output format: dd-MM-yyyy (e.g., 15-07-2025)
        SimpleDateFormat outputFormat = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault());

        try {
            // Parse the input date string into a Date object
            Date date = inputFormat.parse(dateString);

            // Format the Date object into the desired output format
            return outputFormat.format(date);
        } catch (ParseException e) {
            e.printStackTrace();
            // Handle parsing error, e.g., return null or throw an exception
            return null;
        }
    }

    public static void main(String[] args) {
        // Example usage:
        String dateToConvert = "15-Jul-25"; // Current year is 2025
        String convertedDate = convertDateFormat(dateToConvert);

        if (convertedDate != null) {
            System.out.println("Original Date: " + dateToConvert);
            System.out.println("Converted Date: " + convertedDate);
        } else {
            System.out.println("Date conversion failed.");
        }

        String anotherDate = "01-Jan-01"; // Test with year 2001
        String convertedAnotherDate = convertDateFormat(anotherDate);
        if (convertedAnotherDate != null) {
            System.out.println("Original Date: " + anotherDate);
            System.out.println("Converted Date: " + convertedAnotherDate);
        } else {
            System.out.println("Date conversion failed.");
        }
    }
}

Explanation:

SimpleDateFormat inputFormat = new SimpleDateFormat("dd-MMM-yy", Locale.ENGLISH);
This line creates a SimpleDateFormat object to parse your input date string.
"dd-MMM-yy" is the pattern for your input format:
dd: Day of the month (01-31)
MMM: Abbreviated month name (Jan, Feb, Jul, etc.)
yy: Two-digit year (e.g., 25 for 2025)
Locale.ENGLISH is crucial when dealing with month abbreviations (like "Jul") because month names can vary by locale. Using Locale.ENGLISH ensures that "Jul" is correctly interpreted as July.
SimpleDateFormat outputFormat = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault());
This creates another SimpleDateFormat object for the desired output format.
"dd-MM-yyyy" is the pattern for your output format:
dd: Day of the month (01-31)
MM: Month in two digits (01-12)
yyyy: Four-digit year (e.g., 2025)
Locale.getDefault() is generally fine for output unless you have specific locale requirements for the formatted string.
Date date = inputFormat.parse(dateString);
The parse() method attempts to convert the dateString (e.g., "15-Jul-25") into a java.util.Date object according to the inputFormat.
This is where the two-digit year (yy) is expanded into a four-digit year. SimpleDateFormat uses a default century for two-digit years (typically 80 years before the current date to 20 years after). For example, "25" would become 2025, and "90" might become 1990.
return outputFormat.format(date);
The format() method takes the Date object and converts it into a string representation using the outputFormat ("dd-MM-yyyy").
try-catch (ParseException e):
Parsing a date string can fail if the string doesn’t match the expected format. The try-catch block handles ParseException to prevent your app from crashing. You should implement appropriate error handling (e.g., showing a toast message, logging the error, or returning a default value) in a real Android application.

How to use it in Android:

You can place the convertDateFormat method in a utility class or directly within your Activity/Fragment where you need to perform the conversion.

// In your Activity or Fragment:
String originalDate = “15-Jul-25”;
String newFormattedDate = DateConverter.convertDateFormat(originalDate);

if (newFormattedDate != null) {
// Use newFormattedDate, e.g., set it to a TextView
myTextView.setText(newFormattedDate);
} else {
// Handle the error
Toast.makeText(this, “Error converting date”, Toast.LENGTH_SHORT).show();
}

Code to Convert dd-MMM-yy to dd-MM-yyyy in Android Java