BlueNBT

BlueNBT is an NBT (De)Serializer with an API inspired by the GSON library. It's basically GSON for NBT instead of JSON data. If you used GSON before you will feel right at home!

Requirements

BlueNBT requires Java 21

Adding BlueNBT to your Project

Gradle

repositories {
    maven ( "https://repo.bluecolored.de/releases" )
}

dependencies {
    implementation ( "de.bluecolored.bluenbt:BlueNBT:3.0.1" )
}

Maven

<repositories>
    <repository>
        <id>bluecolored</id>
        <url>https://repo.bluecolored.de/releases</url>
    </repository>
</repositories>

<dependency>
    <groupId>de.bluecolored.bluenbt</groupId>
    <artifactId>BlueNBT</artifactId>
    <version>3.0.1</version>
</dependency>

Usage

API Javadoc

The primary class to use is BlueNBT. You can easily create yourself an instance using new BlueNBT(). You can configure each BlueNBT instance separately with different settings and Type(De)Serializers. You can reuse the same BlueNBT instance for as many (de)serialization operations as you like.

First Example

First you want to declare the data-structure that you want to write/read to/from an NBT-Data stream.
For Example:

class MyData {
    int someNumber;
    String someString;
    long[] anArrayOfLongs;
    List<MoreData> aLotMoreData;
}

class MoreData {
    boolean isData;
    Map<String, List<String>> muchData; 
}

Now all you need to do to write all this data to an NBT-file is:

BlueNBT blueNBT = new BlueNBT();
try (
        OutputStream out = Files.newOutputStream(Path.of("myFile.nbt"));
        OutputStream compressedOut = new BufferedOutputStream(new GzipOutputStream(out))
){
    blueNBT.write(myData, compressedOut);
}

And reading it again is equally easy:

BlueNBT blueNBT = new BlueNBT();
try ( 
        InputStream in = Files.newInputStream(Path.of("myFile.nbt"));
        InputStream compressedIn = new BufferedInputStream(new GZIPInputStream(in))
){
    MyData myData = blueNBT.read(compressedIn, MyData.class);
}

Note

Both times we GZIP(De)Compressed our streams before writing/reading. This is because usually all nbt-files are GZIP-Compressed, BlueNBT does not do this for us to allow more flexibility.
Also, make sure to use buffered streams before (de)compression to greatly improve compression-performance.

Using TypeTokens

Sometimes you have a type with generic type-variables that you want to deserialize, for example HashMap<String, Integer>. However, you can't easily create a Class<?> or Type for such a type that you can use to call BlueNBT#read(InputStream in, Class<T> type). This is where TypeTokens come in.
You can create a TypeToken in multiple ways:

// simply from a Class<?> or Type
TypeToken.of(String.class) // String

// for an array of a certain type
TypeToken.array(String.class) // String[]

// for a raw Class<?> with additional type-parameters
TypeToken.of(Map.class, String.class, Integer.class) // Map<String, Integer>

// or by creating a generic anonymous subclass of TypeToken
new TypeToken< Map<String, Collection<Integer>> >() {} // Map<String, Collection<Integer>>

You can then pass this TypeToken to e.g. BlueNBT#read(InputStream in, TypeToken<T> type).

BlueMap-Minecraft/BlueNBT