ViaLoadingBase

Universal ViaVersion, ViaBackwards and ViaRewind standalone implementation

This library is outdated and only maintained to be used in ViaMCP, please use ViaLoader

Contact

If you encounter any issues, please report them on the issue tracker.
If you just want to talk or need help with ViaLoadingBase feel free to join my Discord.

Add this to your own project

build.gradle

repositories {
maven {
url ="https://repo.viaversion.com/"
}
maven {
url ="https://jitpack.io/"
}
}
dependencies {
// https://ci.viaversion.com/
implementation "com.viaversion:viaversion-common:5.0.2-SNAPSHOT"
implementation "com.viaversion:viabackwards-common:5.0.2-SNAPSHOT"
implementation "com.viaversion:viarewind-common:4.0.1-SNAPSHOT"
implementation "org.yaml:snakeyaml:2.2"
implementation "com.github.FlorianMichael:ViaLoadingBase:4.7.0"// https://jitpack.io/#FlorianMichael/ViaLoadingBase// You also need Netty, Guava and Log4j in your class path, but they should be there if your project is based on Minecraft.
implementation "com.google.guava:guava:31.1-jre"
implementation "io.netty:netty-all:5.0.0.Alpha2"
implementation "org.apache.logging.log4j:log4j-core:2.19.0"
}

Which library do I need?

If your platform is older than the latest Minecraft version, you need ViaVersion + ViaBackwards, if your platform is 1.8.x, you need ViaVersion + ViaBackwards + ViaRewind, otherwise you only need ViaVersion:

A 1.8.x Minecraft client for example would need ViaVersion + ViaBackwards + ViaRewind.
A 1.12.x Minecraft client for example would need ViaVersion + ViaBackwards.
A 1.19.x Minecraft client, for example, would need ViaVersion.

Example implementation

publicvoidinit() { // Basic code to load all platforms which are in the class pathViaLoadingBase.ViaLoadingBaseBuilder.
create().
runDirectory(newFile("ViaVersion")).
nativeVersion(47).
build();
}

The most important part is the modification of your netty pipeline. This is needed for ViaVersion to translate the packets in both ways.

finalUserConnectionuser = newUserConnectionImpl(channel, true);
newProtocolPipelineImpl(user);
channel.pipeline().addLast(newVLBPipeline(user) {
@OverridepublicStringgetDecoderHandlerName() {
return"decoder";
}
@OverridepublicStringgetEncoderHandlerName() {
return"encoder";
}
@OverridepublicStringgetDecompressionHandlerName() {
return"decompress";
}
@OverridepublicStringgetCompressionHandlerName() {
return"compress";
}
});

In case your platform has compression, you can call the CompressionReorderEvent at the end of the compression code to correct the compression.

channel.pipeline().fireUserEventTriggered(newCompressionReorderEvent());

ViaLoadingBase will use the provided handler names in the VLB Pipeline in order to do that.

For a mcp based implementation you can have a look at the code in ViaForge

API examples

ViaLoadingBase also offers a system to compare the target version with other versions:

if (ViaLoadingBase.getInstance().getTargetVersion().olderThan(ProtocolVersion.v1_8)) {
// Code is executed when the target version is < than 1.8
}
if (ViaLoadingBase.getInstance().getTargetVersion().olderThanOrEqualTo(ProtocolVersion.v1_16_4)) {
// Code is executed when the target version is < = than 1.16.4
}
if (ViaLoadingBase.getInstance().getTargetVersion().newerThan(ProtocolVersion.v1_12_2)) {
// Code is executed when the target version is > than 1.12.2
}
if (ViaLoadingBase.getInstance().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_14_4)) {
// Code is executed when the target version is > = than 1.14.4
}
if (ViaLoadingBase.getInstance().getTargetVersion().equalTo(ProtocolVersion.v1_10)) {
// Code is executed when the target version is equal to 1.10
}

The versions are compared according to the order in which they are loaded, each protocol version that is loaded gets an
index that is then used for comparison, so if a platform is loaded last, its protocols are treated as oldest.
Below is explained how to determine the pure sequence

To define a range of versions you can use the ProtocolRange class:

finalProtocolRangeallVersionsAbove1_8 = ProtocolRange.andNewer(ProtocolVersion.v1_8);
finalProtocolRangeallVersionsUnder1_12_2 = ProtocolRange.andOlder(ProtocolVersion.v1_12_2);
finalProtocolRangeonly1_18_2 = ProtocolRange.singleton(ProtocolRange.v1_18_2);
if (allVersionsAbove1_8.contains(ProtocolVersion.v1_10)) {
// Check if a version is in the range
}

The class also has a toString() method that automatically formats the range

How to load platforms

publicclassExampleImplementation {
privatefinalPlatformexamplePlatform = newPlatform(
"Example",
() -> ViaLoadingBase.inClassPath("net.exampledev.exampleplatform.ExamplePlatform"), // Checks if the platform class is in the class pathExamplePlatformImpl::new,
protocolVersions -> protocolVersions.addAll(ExamplePlatformVersions.PROTOCOLS));
publicvoidmain() {
ViaLoadingBase.ViaLoadingBaseBuilder.
create().
platform(examplePlatform). // will set the platform as last platform(examplePlatform, 0). // will set the platform as first runDirectory(newFile("ViaVersion")).
nativeVersion(47).
build();
}
}