powernukkit / nbt-manipulator

A kotlin/java lib that allows you to read and write NBT data in a clean way

NBT Manipulator

This is a Kotlin/Java library that allows you to read and write NBT files and data in a clean and simple way.

Can be used both for Minecraft Java and Minecraft Bedrock Edition NBT structures.

Here you can find the library documentation:

• Java Documentation
• Kotlin Documentation

You may also want to see the changelog file to be aware of all changes in the tool that may impact you.

TIP: If you are using NbtList with Kotlin, add a import br.com.gamemods.nbtmanipulator.* for easy list management.

For example:

val list = listOf(2,3,4,5,6).toNbtList()
list += 7
check(7 in list)
list -= 7
check(7 !in list)

Adding to your project

The library is shared in the maven center, so you don't need to declare any custom repository.

Gradle

Kotlin DSL

repositories {
    mavenCentral()
}

dependencies {
    implementation("br.com.gamemods:nbt-manipulator:3.1.0")
}

Groovy DSL

repositories {
    mavenCentral()
}

dependencies {
    implementation 'br.com.gamemods:nbt-manipulator:3.1.0'
}

Maven

<dependencies>
    <dependency>
      <groupId>br.com.gamemods</groupId>
      <artifactId>nbt-manipulator</artifactId>
      <version>3.1.0</version>
    </dependency>
</dependencies>

Ivy

<dependency org="br.com.gamemods" name="nbt-manipulator" rev="3.1.0"/>

Direct JAR

Download it from maven central.

Examples

val compound = NbtCompound()
compound["A string tag"] = "The string tag value"
compound["An int tag"] = 2
val byteValue: Byte = 3
compound["An byte tag"] = byteValue

println(compound.getString("A string tag"))
println(compound.getInt("A string tag"))
println(compound.getInt("An int tag"))
println(compound.getNullableByte("An byte tag"))

println(compound.getNullableStringList("This is missing.."))

val otherConstructor = NbtCompound(
    "a" to NbtString("string"),
    "b" to NbtList(listOf(NbtDouble(0.0), NbtDouble(1.1)))
)
println(otherConstructor["a"])
println(otherConstructor.getDoubleList("b"))

internal fun convertLevelFile(from: File, to: File) {
    val input = NbtIO.readNbtFile(from)
    val inputData = input.compound.getCompound("Data")

    val outputData = NbtCompound()
    outputData.copyFrom(inputData, "GameRules")
    outputData.copyFrom(inputData, "DayTime")
    outputData.copyFrom(inputData, "GameType")
    outputData.copyFrom(inputData, "generatorName")
    outputData.copyFrom(inputData, "generatorVersion")
    outputData.copyFrom(inputData, "generatorVersion")
    outputData.copyFrom(inputData, "generatorOptions", NbtString(""))
    outputData["hardcore"] = false
    outputData["initialized"] = false
    outputData.copyFrom(inputData, "LastPlayed")
    outputData.copyFrom(inputData, "LevelName")
    outputData.copyFrom(inputData, "raining")
    outputData.copyFrom(inputData, "rainTime")
    outputData.copyFrom(inputData, "RandomSeed")
    outputData.copyFrom(inputData, "SizeOnDisk")
    outputData.copyFrom(inputData, "SpawnX")
    outputData.copyFrom(inputData, "SpawnY")
    outputData.copyFrom(inputData, "SpawnZ")
    outputData.copyFrom(inputData, "thundering")
    outputData.copyFrom(inputData, "thunderTime")
    outputData.copyFrom(inputData, "Time")
    outputData.copyFrom(inputData, "version")

    val output = NbtCompound("Data" to outputData)
    val file = NbtFile("", output)
    NbtIO.writeNbtFile(to, file)
}

nbt-manipulator's Issues

NbtIO.writeNbtFile produces ClassCastException

Version: 3.1.0

Thanks for the really useful library, just noticed an issue when using this method:

NbtIO.writeNbtFile(File("test.mcstructure"), NbtFile("", NbtCompound()), compressed=false, littleEndian=true)

which produces:

Exception in thread "main" java.lang.ClassCastException: class java.io.BufferedOutputStream cannot be cast to class java.io.DataOutputStream (java.io.BufferedOutputStream and java.io.DataOutputStream are in module java.base of loader 'bootstrap')
        at br.com.gamemods.nbtmanipulator.LittleEndianDataOutputStream.<init>(LittleEndianDataOutputStream.kt:15)
        at br.com.gamemods.nbtmanipulator.NbtIO.writeNbtFile(NbtIO.kt:42)
        at br.com.gamemods.nbtmanipulator.NbtIO.writeNbtFile(NbtIO.kt:87)
        at br.com.gamemods.nbtmanipulator.NbtIO.writeNbtFile$default(NbtIO.kt:81)

a similar thing also happens with compressed=true