jNBT provides a complete solution for NBT file manipulation with both low-level control and high-level convenience:

• Complete NBT Support - All tags from the official specification
• Fluent Builder API - Modern builder pattern for easy structure creation
• Smart Compression - Automatic detection and support for GZIP, ZLIB, and uncompressed files
• SNBT Support - Parse and generate Stringified NBT for Minecraft commands

You can either import the latest relase .jar file directly as a dependency via your IDE.

Or use a build system of your choosing (e.g. Maven):

<dependencies>
    <dependency>
        <groupId>de.pauleff</groupId>
        <artifactId>jnbt</artifactId>
        <version>1.7.0</version>
    </dependency>
<dependencies>

Read NBT file:

ICompoundTag root = NBTFileFactory.readNBTFile(new File("level.dat"));
String worldName = root.getString("LevelName");

Create with Builder:

ICompoundTag player = NBTBuilder.compound("Player")
    .addString("name", "Steve")
    .addInt("level", 25)
    .addCompound("inventory")
        .addString("item", "diamond_sword")
    .endCompound()
    .build();

Parse SNBT:

ITag<?> tag = NBTFactory.parseFromSNBT("{display:{Name:\"Custom Item\"}}");

Generate SNBT:

SNBTSerializer serializer = new SNBTSerializer();
String snbt = serializer.serialize(tag);

• All NBT tag types (Byte, Short, Int, Long, Float, Double, String, List, Compound, Arrays)
• Complete CRUD operations (Create, Read, Update, Delete)
• Compression formats: GZIP, ZLIB, None
• SNBT (Stringified NBT) parsing and generation
• Many convenience methods

• Bedrock Edition NBT support
• Conversion to JSON
• Graphical NBT editor (maybe)

Explore the examples/ folder for comprehensive usage patterns.

mvn clean install

Always backup your files before modification. While thoroughly tested, data corruption is always possible with file manipulation tools.

This library powers:

• jMCX - Edit Minecraft world files
• MinecraftOfflineOnlineConverter - Player data migration

• Official NBT Format Specification

Minecraft is a registered trademark of Mojang AB.