Kotlin Util Library

This repository contains set of Kotlin-only (no Android dependency) libraries for various purposes.

Data

Kotlin library for data manipulation.

It contains extension methods for ByteArray allowing to read numbers in big-endian and little-endian order in various formats, bit operators for Byte and Short and methods for converting UUIDs to and from ByteArray.

Setting up

Add the following to your build.gradle file:

implementation "no.nordicsemi.kotlin:data:<version>"

Artifacts can be found on Maven Central repository.

Documentation

Dokka documentation can be found here.

Reading Integers

val array = byteArrayOf(0x87.toByte(), 0x65, 0x43, 0x21, 0x21, 0x43, 0x65, 0x87.toByte())
val int1 = array.getInt(offset = 0, format = IntFormat.INT32, order = ByteOrder.BIG_ENDIAN)
val int2 = array.getInt(offset = 4, format = IntFormat.INT32, order = ByteOrder.LITTLE_ENDIAN)
assertEquals(-2023406815, int1)
assertEquals(-2023406815, int2)

Reading Floats

Supported types include:

• IEEE 754 single and double precision
• IEEE 11073 32-bit and 16-bit

val array = byteArrayOf(0xFF.toByte(), 0x00, 0x01, 0x6C, 0x97.toByte(), 0x0D, 0x00, 0xFE.toByte())
val float1 = array.getFloat(0, FloatFormat.IEEE_11073_32_BIT, ByteOrder.BIG_ENDIAN)
val float2 = array.getFloat(4, FloatFormat.IEEE_11073_32_BIT, ByteOrder.LITTLE_ENDIAN)
assertEquals(36.4f, float1)
assertEquals(34.79f, float2)

Bit operators

The library also contains extension methods for Byte allowing to perform bitwise operations.

val value = 0b1010_1001.toByte()
assertTrue(value hasAllBitsSet 0b1000_0001)

val value = 0b1010_1001.toByte()
assertTrue(value hasBitSet 0)
assertFalse(value hasBitCleared 0)

 val value = 0b1010_1001_1010_1001.toShort()
assertEquals(0b1101_0100_1101_0100.toShort(), value shr 1)
assertEquals(0b1111_1010_1001_1010.toShort(), value shr 4)

UUID

The library also contains extension methods for ByteArray allowing to convert UUIDs to and from ByteArray.

val uuid1 = UUID.randomUUID()
val array = uuid1.toByteArray(order = ByteOrder.BIG_ENDIAN)
val uuid2 = array.toUuid(order = ByteOrder.BIG_ENDIAN)
assertEquals(uuid, uuid2)