How to Convert String to Date Time in Scala?

In this article, we will learn how to convert String to DateTime in Scala. Converting String to DateTime consists of parsing a textual representation of date and time into a structured DateTime object for further manipulation and processing in Scala programs.

Using SimpleDateFormat

1. In this approach, we are using the SimpleDateFormat class from Java’s standard library to parse a user-inputted date and time string (userInput) in the format “yyyy-MM-dd HH:mm:ss” into a Date object (res).
2. The SimpleDateFormat object (dFormat) is initialized with the desired date-time format, and the parse method is used to convert the string into a Date object based on this format.
3. Finally, the parsed Date object is printed to the console using println.

In the below example, the SimpleDateFormat library is used to convert String to date time.

Scala

// importing necessary classes from Java
import java.text.SimpleDateFormat
import java.util.Date

// Creating object GFG
object GFG {
  // Main method
  def main(args: Array[String]): Unit = {

    // Input string representing date and time
    val userInput = "2024-03-27 13:30:00"

    // Creating SimpleDateFormat object with the desired date-time format
    val dFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")

    // Parsing the input string to obtain a Date object
    val res = dFormat.parse(userInput)

    // Printing the parsed Date
    println("Parsed Date: " + res)
  }
}

Output:

Using SimpleDateFormat with Calender

1. In this approach, we are using a combination of SimpleDateFormat and Calendar classes from the Java standard library to parse a date and time string (“yyyy-MM-dd HH:mm:ss“) into a Date object.
2. The SimpleDateFormat instance dFormat is used to specify the date-time format for parsing.
3. The Calendar instance cal is then used to set the parsed date and time values, which are obtained as a Date object (res) and printed to the console.

In the below example, the SimpleDateFormat with Calender is used to convert String to date time.

Scala

import java.text.SimpleDateFormat
import java.util.Calendar

// Creating Objext
object GFG {

  // Main Method
  def main(args: Array[String]): Unit = {

    // Input string representing date and time
    val dInput = "2024-03-27 13:30:00"

    // Creating a SimpleDateFormat object to parse the input string
    val dFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")

    // Creating a Calendar instance to work with date and time
    val cal = Calendar.getInstance()

    // Parsing the input string to obtain a Date object
    cal.setTime(dFormat.parse(dInput))

    // Getting the Date object from the Calendar instance
    val res = cal.getTime()

    // Printing the parsed date
    println("Parsed Date: " + res)
  }
}

Output:

Using Simple Parsing

1. In this approach, we are using simple parsing techniques in Scala to convert a string representing a date (“2024-03-27”) into a GregorianCalendar object.
2. The simpleParse method splits the input string by hyphens and attempts to create a calendar object based on the parsed components (year, month, day).
3. If successful, it returns an Option[GregorianCalendar] representing the parsed date; otherwise, it returns None.

In the below example, the Simple Parsing is used to convert String to date time.

Scala

import java.util.{Calendar, GregorianCalendar}

class GFG {
  def simpleParse(dateString: String): Option[GregorianCalendar] = {
    dateString.split("-").toList match {
      case yyyy :: mm :: dd :: Nil =>
        try {
          Some(new GregorianCalendar(yyyy.toInt, mm.toInt - 1, dd.toInt))
        } catch {
          case _: NumberFormatException => None
        }
      case _ => None
    }
  }
}

object GFG extends App {
  val parser = new GFG

  // Input string representing date
  val dInput = "2024-03-27"

  // Parse the input string using simple parsing
  val maybeDate = parser.simpleParse(dInput)

  // Print the parsed DateTime object
  maybeDate match {
    case Some(date) =>
      println("Parsed DateTime: " + date.getTime)
    case None =>
      println("Invalid date format")
  }
}

Output:

Using Regular Expressions

1. In this approach, we are using regular expressions (Regex) in Scala to match and extract date components from a string with a specific format (yyyy-MM-dd HH:mm:ss).
2. The parseDate method checks if the input string matches the regex pattern and extracts the year, month, day, hour, minute, and second components.
3. If the format is valid, it constructs a GregorianCalendar object based on the extracted components, otherwise returning None.

In the below example, the Regular Expressions is used to convert String to date time.

Scala

import java.util.{Calendar, GregorianCalendar}
import scala.util.matching.Regex

object GFG {
  def parseDate(dateString: String): Option[GregorianCalendar] = {
    val dateRegex = """(\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2})""".r
    dateString match {
      case dateRegex(year, month, day, hour, minute, second) =>
        try {
          Some(new GregorianCalendar(year.toInt, month.toInt - 1, day.toInt))
        } catch {
          case _: NumberFormatException => None
        }
      case _ => None
    }
  }

  def main(args: Array[String]): Unit = {
    val dInput = "2024-03-27 13:30:00"
    val maybeDate = parseDate(dInput)

    maybeDate match {
      case Some(date) =>
        println("Parsed DateTime: " + date.getTime)
      case None =>
        println("Invalid date format")
    }
  }
}

Output: