Backpacker for Kotlin

Pack your data into a tiny backpack

Backpacker is a convenient way to serialize data using Protobuffers. Read the main page of the project to get fully introduced to Backpack. This readme is intended to explain how to use Backpack in Kotlin.

Give me an example

If you want to serialize a Person like this:

data class Person(
        val name: String,
        val birthday: Date,
        val fingers: Int,
        val hands: Int)

You'll need to write a PersonBackpacker class that extends CustomBackpacker like this:

class PersonBackpacker : CustomBackpacker<Person>() {

    override fun toBytes(person: Person): ByteArray {
        val backpack = Backpack(
                string1 = person.name,
                long1 = person.birthday.time,
                integer1 = person.fingers,
                integer2 = person.hands
        )
        return Backpacker().toBytes(backpack)
    }

    override fun fromBytes(bytes: ByteArray): Person {
        val backpack = Backpacker().fromBytes(bytes)
        return Person(
                name = backpack.string1!!,
                birthday = Date(backpack.long1!!),
                fingers = backpack.integer1!!
                hands = backpack.integer2!!
        )
    }
}

And that's all. The PersonBackpacker will give you four methods:

• toBytes(person) that receives a person and returns a byte array
• toBytesList(persons) that receives a list of persons and returns a byte array
• fromBytes(bytes) that receives a byte array and returns a person
• fromBytesList(bytes). that receives a byte array and returns a list of persons

Download

• Grab via Gradle:

repositories { jcenter() }
    
compile 'com.github.backpacker:backpacker:1.0.0'

• Grab via Maven:

<repository>
  <id>jcenter</id>
  <url>http://jcenter.bintray.com</url>
</repository>

<dependency>
    <groupId>com.github.backpacker</groupId>
    <artifactId>backpacker</artifactId>
    <version>1.0.0</version>
</dependency>