Top Android Date and Time Libs

As developers, we've all been there: staring at the clock, trying to tame the wild stallions of dates and times. Let's examine some of the most esteemed DateTime libraries for Kotlin on Android, and see how they can make our lives easier.

1. Joda-Time

Once upon a time, in a land before Java 8, there was Joda-Time. It was the brainchild of developers who sought to bring sanity to the wilderness of Java's date and time APIs. Although Java 8 introduced its own DateTime API, Joda-Time remains a trusted companion for those on earlier versions or seeking additional functionality.

Features

  • Immutable date and time objects
  • Extensive support for time zones and daylight savings
  • Period and duration handling
  • Extensive set of chronologies, supporting non-ISO calendars
  • Formatting and parsing

Installation

Add the dependency to your build.gradle file:

dependencies {
    implementation 'joda-time:joda-time:2.10.10'
}

Code Example

import org.joda.time.DateTime
import org.joda.time.format.DateTimeFormat

val dateTime = DateTime.now()
val formatter = DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss")
val formattedDateTime = dateTime.toString(formatter)

println("Current date and time: $formattedDateTime")

In this snippet, we're using Joda-Time to get the current date and time and format it according to our pattern.

Comparison

Joda-Time is more comprehensive than Java's original Date and Calendar classes but is now largely superseded by the java.time package in Java 8. However, it's still a solid choice for those not yet on Java 8 or for specific features it offers over the standard library.

Reference

2. ThreeTenABP

Introduction

ThreeTenABP is the Android Backport of the JSR-310 Date and Time API introduced in Java 8. It brings the modern java.time API to earlier Android versions, ensuring you don't have to sacrifice functionality for compatibility.

Features

  • Backport of Java 8's java.time API
  • Immutable date and time objects
  • Extensive time zone and daylight savings support
  • Interoperability with Java's util.Date and Calendar
  • Formatting and parsing

Installation

Add the dependency to your build.gradle file:

dependencies {
    implementation 'com.jakewharton.threetenabp:threetenabp:1.3.1'
}

Code Example

import org.threeten.bp.LocalDateTime
import org.threeten.bp.format.DateTimeFormatter

val currentTime = LocalDateTime.now()
val formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")
val formattedTime = currentTime.format(formatter)

println("Current time in custom format: $formattedTime")

Here, we're using ThreeTenABP to fetch the current time and format it. The API feels familiar to those who have used Java 8's java.time package.

Comparison

ThreeTenABP is the go-to for developers who want the Java 8 java.time experience on Android. It's a thin layer over the standard library, offering the same API with the added benefit of working on older Android versions.

Reference

3. kotlinx-datetime

Introduction

kotlinx-datetime is the Kotlin standard library's answer to date and time manipulation. It's designed with Kotlin's idiomatic style in mind, providing a concise and intuitive API for developers.

Features

  • Kotlin-friendly API
  • Immutable date and time objects
  • Time zone support
  • Interoperation with Java's java.time API
  • Formatting and parsing with kotlinx-datetime-formatter module

Installation

Add the dependency to your build.gradle file:

dependencies {
    implementation "org.jetbrains.kotlinx:kotlinx-datetime:0.3.0"
}

For formatting, you'll also need:

dependencies {
    implementation "org.jetbrains.kotlinx:kotlinx-datetime-formatter:0.3.0"
}

Code Example

import kotlinx.datetime.LocalDateTime
import kotlinx.datetime.TimeZone
import kotlinx.datetime.toLocalDateTime

val currentTime = Clock.System.now().toLocalDateTime(TimeZone.currentSystemDefault())

println("Current date and time: $currentTime")

In this example, we're using kotlinx-datetime to get the current date and time, taking into account the system's default time zone.

Comparison

kotlinx-datetime is the new kid on the block, offering a Kotlin-first approach to date and time manipulation. It's less mature than Joda-Time or ThreeTenABP but is rapidly gaining features and community support.

Reference