build.gradle

buildscript {
    repositories {
        mavenCentral()
        maven {
            url = 'http://files.minecraftforge.net/maven'
        }
        maven {
            url = 'http://repo.minecrell.net/releases'
        }
    }

    dependencies {
        classpath 'net.minecraftforge.gradle:ForgeGradle:2.1-SNAPSHOT'
        classpath 'net.minecrell:VanillaGradle:2.0.3_1'
    }
}

group pluginGroup
version pluginVersion

apply plugin: 'net.minecrell.vanilla.server.library'
apply plugin: 'java'

sourceCompatibility = 1.8
targetCompatibility = 1.8

minecraft {
    version = project.minecraftVersion
    mappings = project.mcpMappings
}

repositories {
    mavenCentral()
    maven {
        name = 'spongepowered-repo'
        url = 'http://repo.spongepowered.org/maven/'
    }
}

dependencies {
    testCompile group: 'junit', name: 'junit', version: '4.11'
    compile 'org.spongepowered:spongeapi:5.0.0-SNAPSHOT'
}

error

:deobfCompileDummyTask
:deobfProvidedDummyTask
:getVersionJson
:extractDependencyATs SKIPPED
:extractMcpData SKIPPED
:extractMcpMappings SKIPPED
:genSrgs SKIPPED
:downloadServer SKIPPED
:splitServerJar SKIPPED
:deobfMcSRG SKIPPED
:decompileMc FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':decompileMc'.
> java.lang.NullPointerException (no error message)

* Try:
Run with --info or --debug option to get more log output.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':decompileMc'.
	at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:69)
	at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:46)
	at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:35)
	at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:68)
	at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
	at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:52)
	at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
	at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:53)
	at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
	at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:203)
	at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:185)
	at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:66)
	at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50)
	at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
	at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
Caused by: java.lang.NullPointerException
	at org.jetbrains.java.decompiler.main.Fernflower.getClassEntryName(Fernflower.java:76)
	at org.jetbrains.java.decompiler.struct.ContextUnit.save(ContextUnit.java:150)
	at org.jetbrains.java.decompiler.struct.StructContext.saveContext(StructContext.java:72)
	at org.jetbrains.java.decompiler.main.Fernflower.decompileContext(Fernflower.java:62)
	at org.jetbrains.java.decompiler.main.decompiler.BaseDecompiler.decompileContext(BaseDecompiler.java:41)
	at net.minecraftforge.gradle.tasks.ApplyFernFlowerTask.applyFernFlower(ApplyFernFlowerTask.java:101)
	at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:75)
	at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.doExecute(AnnotationProcessingTaskFactory.java:228)
	at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:221)
	at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:210)
	at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:585)
	at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:568)
	at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:80)
	at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:61)
	... 14 more


BUILD FAILED

Total time: 20.427 secs

gradle.properties

pluginGroup=com.demonwav
pluginVersion=1.0-SNAPSHOT
minecraftVersion=1.10.2
mcpMappings=snapshot_20160920