xref: /aosp_15_r20/external/kotlinx.serialization/guide/example/example-formats-13.kt (revision 57b5a4a64c534cf7f27ac9427ceab07f3d8ed3d8)
1 // This file was automatically generated from formats.md by Knit tool. Do not edit.
2 package example.exampleFormats13
3 
4 import kotlinx.serialization.*
5 import kotlinx.serialization.descriptors.*
6 import kotlinx.serialization.encoding.*
7 import kotlinx.serialization.modules.*
8 
9 class ListEncoder : AbstractEncoder() {
10     val list = mutableListOf<Any>()
11 
12     override val serializersModule: SerializersModule = EmptySerializersModule()
13 
encodeValuenull14     override fun encodeValue(value: Any) {
15         list.add(value)
16     }
17 
beginCollectionnull18     override fun beginCollection(descriptor: SerialDescriptor, collectionSize: Int): CompositeEncoder {
19         encodeInt(collectionSize)
20         return this
21     }
22 }
23 
encodeToListnull24 fun <T> encodeToList(serializer: SerializationStrategy<T>, value: T): List<Any> {
25     val encoder = ListEncoder()
26     encoder.encodeSerializableValue(serializer, value)
27     return encoder.list
28 }
29 
encodeToListnull30 inline fun <reified T> encodeToList(value: T) = encodeToList(serializer(), value)
31 
32 class ListDecoder(val list: ArrayDeque<Any>, var elementsCount: Int = 0) : AbstractDecoder() {
33     private var elementIndex = 0
34 
35     override val serializersModule: SerializersModule = EmptySerializersModule()
36 
37     override fun decodeValue(): Any = list.removeFirst()
38 
39     override fun decodeElementIndex(descriptor: SerialDescriptor): Int {
40         if (elementIndex == elementsCount) return CompositeDecoder.DECODE_DONE
41         return elementIndex++
42     }
43 
44     override fun beginStructure(descriptor: SerialDescriptor): CompositeDecoder =
45         ListDecoder(list, descriptor.elementsCount)
46 
47     override fun decodeSequentially(): Boolean = true
48 
49     override fun decodeCollectionSize(descriptor: SerialDescriptor): Int =
50         decodeInt().also { elementsCount = it }
51 }
52 
decodeFromListnull53 fun <T> decodeFromList(list: List<Any>, deserializer: DeserializationStrategy<T>): T {
54     val decoder = ListDecoder(ArrayDeque(list))
55     return decoder.decodeSerializableValue(deserializer)
56 }
57 
decodeFromListnull58 inline fun <reified T> decodeFromList(list: List<Any>): T = decodeFromList(list, serializer())
59 
60 @Serializable
61 data class Project(val name: String, val owners: List<User>, val votes: Int)
62 
63 @Serializable
64 data class User(val name: String)
65 
66 fun main() {
67     val data = Project("kotlinx.serialization",  listOf(User("kotlin"), User("jetbrains")), 9000)
68     val list = encodeToList(data)
69     println(list)
70     val obj = decodeFromList<Project>(list)
71     println(obj)
72 }
73