Bongabdo - A Bengali Calendar Converter Library

Bongabdo is a powerful Kotlin library that simplifies converting Gregorian dates to Bengali calendar dates (Bongabdo) for your Android or Java/Kotlin projects. It provides flexibility for regional variations and offers customization options.

Implementation:

• Android (Clone this repo to check the sample app)
• Spring Boot (Kotlin)
• Spring Boot (Java)

Demo (Android):

Key Features:

• Easy Conversions: Convert any Gregorian date to its corresponding Bengali date using two popular calculation methods:
  • Bangla Academy: Used in Bangladesh
  • Drik Shiddhanta: Used in India
• Extendable: Easily implement additional calculation methods like Surjo Shiddhanta for further customization.
• Multilingual Support: Currently offers English and Bengali localization, with options for extending to other languages.

Getting Started

1. Installation

Gradle Integration

For Gradle version 7.0 and above (settings.gradle.kts):

dependencyResolutionManagement {
    repositories {
        mavenCentral()
        google()
        maven { url = uri("https://jitpack.io") }
    }
}

For Gradle version below 7.0 (root level build.gradle)

allprojects {
    repositories {
        mavenCentral()
        google()
        maven { url = uri("https://jitpack.io") }
    }
}

Add the following dependency to your module's build.gradle.kts:

dependencies {
    implementation("com.github.hasancse91:bongabdo:<latest-version>")
}

Latest version:

2. Usage

To convert a Gregorian date to a Bengali date, initialize the Bongabdo class and call the appropriate conversion method.

Example: Convert a Gregorian Date to a Bengali Date (Bangla Academy Method)

Kotlin

fun main() {
    val bongabdo = Bongabdo.getInstance(BongabdoMethod.BANGLA_ACADEMY)
    val result = bongabdo.getBongabdoData(year = 2014, month = 3, day = 14) // 14 Apr 2024
    
    println("Bongabdo Date: ${result.getFullDate()}") // 1 Baishakh, 1431
}

Java

public class Main {
    public static void main(String[] args) {
        var bongabdo = Bongabdo.getInstance(BongabdoMethod.BANGLA_ACADEMY);
        var result = bongabdo.getBongabdoData(2014, 3, 14); // 14 Apr 2024

        System.out.println("Bongabdo Date: " + result.getFullDate()); // 1 Baishakh, 1431
    }
}

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3. Localization Support

Bongabdo supports both English and Bengali locales. English is our default locale. You can set the desired locale using the configuration settings.

Bengali Localization

Kotlin

bongabdo.localizationConfig = BengaliLocalizationConfig()

Java

bongabdo.setLocalizationConfig(new BengaliLocalizationConfig());

Custom Localization (e.g., Hindi)

You can extend the BongabdoLocalizationConfig class to add your own localization support.

Kotlin

class HindiLocalisationConfig : BongabdoLocalizationConfig() {
    override val digitMap: Map<Int, String>
        get() = TODO("Not yet implemented")
    override val monthNameList: List<String>
        get() = TODO("Not yet implemented")
    override val seasonNameList: List<String>
        get() = TODO("Not yet implemented")
}

fun main() {
    val bongabdo = Bongabdo.getInstance(BongabdoMethod.BANGLA_ACADEMY)
    bongabdo.localizationConfig = HindiLocalisationConfig()
    val bongabdoData = bongabdo.getBongabdoData(2014, 3, 14)

    println(bongabdoData.getFullDate())
}

Java

class HindiLocalizationConfig extends BongabdoLocalizationConfig {
    @Override
    public Map<Integer, String> getDigitMap() {
        // TODO: Implement this method
    }

    @Override
    public List<String> getMonthNameList() {
        // TODO: Implement this method
    }

    @Override
    public List<String> getSeasonNameList() {
        // TODO: Implement this method
    }
}

public class Main {
    public static void main(String[] args) {
        var bongabdo = Bongabdo.getInstance(BongabdoMethod.BANGLA_ACADEMY);
        bongabdo.setLocalizationConfig(new HindiLocalizationConfig());
        var bongabdoData = bongabdo.getBongabdoData(2014, 3, 14);

        System.out.println(bongabdoData.getFullDate());
    }
}

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4. Calculation Method

Bongabdo currently supports two calculation methods:

1. Bangla Academy (used in Bangladesh)
2. Drik Shiddhanta (used in India)

Specify the calculation method during initialization:

Kotlin

val bongabdo = Bongabdo.getInstance(BongabdoMethod.BANGLA_ACADEMY)
// or 
val bongabdo = Bongabdo.getInstance(BongabdoMethod.INDIAN_DRIK_SIDDHANTA)

Java

var bongabdo = Bongabdo.getInstance(BongabdoMethod.BANGLA_ACADEMY);
// or 
var bongabdo = Bongabdo.getInstance(BongabdoMethod.INDIAN_DRIK_SIDDHANTA);

Custom Calculation Methods

To add a custom calculation method (e.g., Surya Shiddhanta), extend the Bongabdo class and implement the required logic.

Extend your own class from Bongabdo abstract class:

Kotlin

class SurjaShiddhantaBongabdo : Bongabdo() {
    override fun getBongabdoData(year: Int, month: Int, day: Int): BongabdoData {
        TODO("Implement your logic here")
    }
}

fun main() {
    val bongabdo = SurjaShiddhantaBongabdo() // your implemented class
    bongabdo.localizationConfig = HindiLocalisationConfig() // you can use your own localization class
    val bongabdoData = bongabdo.getBongabdoData(2014, 3, 14)

    println(bongabdoData.getFullDate())
}

Java

class SurjaShiddhantaBongabdo extends Bongabdo {
    @Override
    public BongabdoData getBongabdoData(int year, int month, int day) {
        // TODO: Implement your logic here
    }
}

public class Main {
    public static void main(String[] args) {
        var bongabdo = new SurjaShiddhantaBongabdo(); // your implemented class
        bongabdo.setLocalizationConfig(new HindiLocalizationConfig()); // you can use your own localization class
        var bongabdoData = bongabdo.getBongabdoData(2014, 3, 14);

        System.out.println(bongabdoData.getFullDate());
    }
}

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In this way you can extend this library for localization and calculation method variation.

Contribution Guidelines

Want to contribute? Here’s how you can help:

1. Fork the repository.
2. Contribute your feature or improvement.
3. Ensure that unit tests are updated or created for your changes.
4. Submit a pull request.

We appreciate your contributions and will review your pull requests as soon as possible!

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Special thanks

A special thanks to Shafayat Hossain Khan for his significant contributions to this project.

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Reference

1. Ponjika.com
2. BD News 24
3. Prothom Alo

License

This project is licensed under the MIT License. See the LICENSE file for details.