Hi Everyone, I'm quite new with Kotlin and KMP. I'...

# multiplatform

[Dejan Lozanovic]

Hi Everyone, I'm quite new with Kotlin and KMP. I'm curious is there any equivalent for java.nio.ByteBuffer in KMP or other libraries that are compatible with KMP(serialization or ktor or something else). I need to wrap it around ByteArray and I do need to read/write Ints, Shorts, Longs, Floats etc..
Thanks in advance.

[ephemient]

ktor has https://api.ktor.io/ktor-io/io.ktor.utils.io/-byte-read-channel/index.html

[ephemient]

it used to have its own Buffer type, it's moving to kotlinx-io. Buffer is a bit more than you need (despite the similar name, it's a different set of functionality than nio buffers) but if you just need to put a ByteArray in and get Int etc. out, it'll do

[Michael Paus]

You can use Kotlinx-IO, Ktor or Okio for this. The following examples take a ByteArray bytes and create a ShortArray shorts by reading short values from the buffer.

With Kotlinx-IO it looks like this:

Buffer().apply {
    write(bytes)
    shorts = ShortArray(NUM_VALUES) { readShort() }
}

With Ktor it looks like this:

ByteReadChannel(bytes).apply {
    runBlocking {
        shorts = ShortArray(NUM_VALUES) { readShort() }
    }
}

With Ktor you have to deal with the fact that the read methods are suspending functions whereas in Kotlinx-IO they are not.