@Date Kotlin Multi Modules Project

This project is a multi modules for @Date. The project is a proof of concept for the design part of thesis project "Date-Time Data Type Problem and Vision" published at Kristianstad University.

The project includes the following modules:

• @Date root module (at-date)
• @Date Library (at-date-lib)
• @Date Console Application (at-date-console)
• @Date Web Api (at-date-api)

@Date Kotlin Library (at-date-lib)

Overview

This library does encode and decode Moment and Period notations using the @Date format.

It provides Models for AtDate, Moment and Period. It also provides a set of functions to encode and decode Moment and Period notations.

Usage

It's used by @Date Kotlin Console Application (at-date-console) and @Date Kotlin Web Api (at-date-api).

Examples

// Encode AtDate notation into Moment class
val atDate: AtDate = encode("@2019-05-05 { d:1 }@")
println(atDate) // Moment(rangeLevel=Level1, resolutionLevel=Level0, zoneLevel=Level0, accuracy=Start, leapSecondsFlag=0, date=1009, time=null, zone=null, plusLeapSeconds=null, minusLeapSeconds=null)

Future Work

• Publish it to Maven Central.
• Cover Arithmetic and Logical operations.
• Encode/decode date-time with level or resolution above 15: The code in Kotlin uses a variable of kind ULong which is only 8 bytes long. A different kind of coding should be used, maybe Array of UByte.
• Enhance Unit test in implementation.

@Date Kotlin Console Application (at-date-console)

Overview

This application does encode and decode Moment and Period notations to/from bits representation using c/java/kotlin hexadecimal format.

Usage

To use the application, follow these steps:

1. Clone the repository or download the source code.

2. Open the project in your preferred Kotlin IDE as Gradle project.

3. Locate the Main.kt file in the com.amerharb.atdate package.

4. Run the Main class.

5. Enter the Moment or Period notation or payload (bits representation) to encode or decode.

   • if you start with @ then the application will encode the notation into payload (bits representation).

   > @2019-05-05@
   Hex: 0xc007e2
   Bin: 0b110000000000011111100010
   >

   • if you start with 0x then the application will decode payload into @Date notation.

   > 0xc007e2
   Notation: @2019-05-05 { d:1 t:0 z:0 a:s l:0-0 }@
   >

Examples

@Date
input:
enter @...@ to encode, 0x... to decode or Q to Quit
>@2019-05-05@
Hex: 0xc007e2
Bin: 0b110000000000011111100010
>0xc007e2
Notation: @2019-05-05 { d:1 t:0 z:0 a:s l:0-0 }@
>@2019-05-05T19:53:00+02:00 {d:1 t:5 a:s l:0-0 z:1}@
Hex: 0xd607e3179c10
Bin: 0b110101100000011111100011000101111001110000010000
>@P-tp@
Hex: 0xa0
Bin: 0b10100000
>@P+1D { d:1 t:0 l:0-0 }@
Hex: 0x880002
Bin: 0b100010000000000000000010
>0x880002
Notation: @P+1D { d:1 t:0 l:0-0 }@
>0xa0
Notation: @P-tp@
>Q
Exiting with status 0

Process finished with exit code 0

Future Work

• Cover Arithmetic and Logical operations when Lib support it.

@Date Kotlin Web Api (at-date-api)

Overview

Provide endpoints that encode and decode Moment and Period notations to/from hexadecimal or base64.

endpoints

• GET /encode/{notation} to encode Moment or Period notation to hexadecimal. it returns:

hex: 0x......
base64: ......

example:

GET /encode/@2019-05-05@

hex: 0xc007e2
base64: wAfi

• GET /encode/{notation}/hex to encode Moment or Period notation to hex.

example:

GET /encode/@2019-05-05@/hex

0xc007e2

• GET /encode/{notation}/base64 to encode Moment or Period notation to base64.

example:

GET /encode/@2019-05-05@/base64

wAfi

• GET /decode/hex/{hex} to decode hexadecimal to Moment or Period notation.

example:

GET /decode/hex/0xc007e2

@2019-05-05 { d:1 t:0 z:0 a:s l:0-0 }@

• GET /decode/base64/{base64} to decode base64 to Moment or Period notation.

example:

GET /decode/base64/wAfi

@2019-05-05 { d:1 t:0 z:0 a:s l:0-0 }@

Future Work

• Support binary.

Future Work

• Add at-date-web module for a web page that demonstrate the design.

License

This project is licensed under the ISC License.