Hello, I am working on a mod and I am using a custom dependency. I added the jar files according to the docs and used a build.gradle based on PaleoCrafter.

If I open the jar file I can see all of the .meta and .jar files and I can also see forge extracting them into the mods/1.12.2 folder. But when the game is launched the mod crashes during initialization due to 

java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/ObjectMapper
  Caused by: java.lang.ClassNotFoundException: com.fasterxml.jackson.databind.ObjectMapper

It runs fine in intellij

This is my build.gradle:

buildscript {
    repositories {
        jcenter()
        maven { url = "https://files.minecraftforge.net/maven" }
    }
    dependencies {
        classpath 'net.minecraftforge.gradle:ForgeGradle:2.3-SNAPSHOT'
    }
}

apply plugin: 'net.minecraftforge.gradle.forge'
//Only edit below this line, the above code adds and enables the necessary things for Forge to be setup.

version = "1.0"
group = "com.suppergerrie2.dependencytest"
archivesBaseName = "sdependencytest"

repositories {
    mavenLocal()
}

sourceCompatibility = targetCompatibility = '1.8'
compileJava {
    sourceCompatibility = targetCompatibility = '1.8'
}

minecraft {
    version = "1.12.2-14.23.5.2814"
    runDir = "run"
    
    mappings = "stable_39"
}

processResources {
    inputs.property "version", project.version
    inputs.property "mcversion", project.minecraft.version

    from(sourceSets.main.resources.srcDirs) {
        include 'mcmod.info'

        expand 'version':project.version, 'mcversion':project.minecraft.version
    }

    from(sourceSets.main.resources.srcDirs) {
        exclude 'mcmod.info'
    }
}

//From https://github.com/PaleoCrafter/Dependency-Extraction-Example/blob/library-embedding/build.gradle
configurations {
    // Configuration that holds JARs to embed inside the mod JAR
    embed
    // Make embedded dependencies actually available during compilation/to IDEs
    compile.extendsFrom embed
}

dependencies {
    embed group: 'com.schematical.chaosnet', name: 'ChaosNet', version: '1.0-SNAPSHOT'
}

// Custom task to generate the metadata files required for our dependencies
task generateMetaFiles {
    // Code for execution after the whole buildscript was parsed and loaded
    doLast {
        // Clear the dependencyMeta directory since we don't want old dependencies to still be listed in there
        file("${buildDir}/dependencyMeta/").deleteDir()
        configurations.embed.resolvedConfiguration.resolvedArtifacts.each {
            // Create a meta file for each dependency in a specified directory
            def metaFile = file("${buildDir}/dependencyMeta/${it.file.name}.meta")
            metaFile.parentFile.mkdirs()
            // Use the Gradle notation provided by the API ('group:artifact:version') for the meta file...
            def artifactRef = it.moduleVersion.toString()
            // ...and append the classifier if present
            if (it.classifier != null) {
                artifactRef += ":${it.classifier}"
            }
            // Write the artifact information to the meta file, to be used by the
            metaFile.text = "Maven-Artifact: $artifactRef"
        }
    }
}

// Use the standard JAR task as container for the main jar and the contained dependencies (from the embed configuration)
jar {
    into('/META-INF/libraries/') {
        // Add all of the dependency JARs to the main JAR for later extraction
        from configurations.embed
        // Also include all dependency meta files
        from "${buildDir}/dependencyMeta/"
    }
    manifest {
        // The crucial manifest attribute: Make Forge extract the contained JARs
        attributes 'ContainedDeps': configurations.embed.collect { it.name }.join(' ')
    }
    // Only run the main jar task after the meta files were built
    dependsOn generateMetaFiles
}

And this is the only class in the mod:

package com.suppergerrie2.dependencytest;

import com.schematical.chaosnet.ChaosNet;
import net.minecraftforge.fml.common.Mod;
import net.minecraftforge.fml.common.Mod.EventHandler;
import net.minecraftforge.fml.common.event.FMLInitializationEvent;
import net.minecraftforge.fml.common.event.FMLPreInitializationEvent;
import org.apache.logging.log4j.Logger;

@Mod(modid = TestMod.MODID, name = TestMod.NAME, version = TestMod.VERSION)
public class TestMod {
    public static final String MODID = "sdependencytest";
    public static final String NAME = "Test Mod";
    public static final String VERSION = "1.0";

    private static Logger logger;

    @EventHandler
    public void preInit(FMLPreInitializationEvent event) {
        logger = event.getModLog();

        ChaosNet sdk =  ChaosNet.builder()
                .build();

        logger.info(sdk);
    }

    @EventHandler
    public void init(FMLInitializationEvent event) {
    }
}

 

Edited May 4, 20196 yr by suppergerrie2

Anyone have an idea for a solution? I know some dependencies are loaded because it can find some of the classes from the dependencies.

Does that specific class get put inside your jar and then extracted properly?

The jar gets put into META-INF/libraries and extracted to mods/1.12.2 on game launch. I know at least some of the jar files are loaded because it can find classes from ChaosNet-1.0-SNAPSHOT.jar.

debug.log

Edited May 16, 20196 yr by suppergerrie2
Added debug.log

What about that specific class?

Well the class is in extracted the jar file:

Edited May 16, 20196 yr by suppergerrie2

Any more info you need?

So, any more info needed? Logs or something?

I have no idea what could cause this, my best idea is to attach a debugger to the running minecraft instance and try and debug what’s causing it to fail