Run Mercury in a separate process for memory issues

This allows paperweight to work without requiring the daemon to have
more memory.

src/main/kotlin/Paperweight.kt

@@ -74,6 +74,7 @@ import io.papermc.paperweight.util.ext
 import io.papermc.paperweight.util.fromJson
 import io.papermc.paperweight.util.gson
 import io.papermc.paperweight.util.registering
+import java.io.File
 import org.gradle.api.Plugin
 import org.gradle.api.Project
 import org.gradle.api.Task
@@ -82,7 +83,6 @@ import org.gradle.api.tasks.Delete
 import org.gradle.api.tasks.TaskProvider
 import org.gradle.kotlin.dsl.maven
 import org.gradle.kotlin.dsl.register
-import java.io.File
 
 class Paperweight : Plugin<Project> {
     override fun apply(target: Project) {
@@ -454,8 +454,7 @@ class Paperweight : Plugin<Project> {
             dependsOn(patchSpigot)
             apiPom.set(patchSpigotApi.flatMap { it.outputDir.file("pom.xml") })
             serverPom.set(patchSpigotServer.flatMap { it.outputDir.file("pom.xml") })
-            apiOutputDir.set(cache.resolve(Constants.SPIGOT_API_JARS_PATH))
-            serverOutputDir.set(cache.resolve(Constants.SPIGOT_SERVER_JARS_PATH))
+            outputDir.set(cache.resolve(Constants.SPIGOT_JARS_PATH))
         }
 
         val remapSpigotAt by tasks.registering<RemapSpigotAt> {
@@ -470,8 +469,7 @@ class Paperweight : Plugin<Project> {
             mappings.set(generateSpigotSrgs.flatMap { it.spigotToSrg })
             vanillaJar.set(downloadServerJar.flatMap { it.outputJar })
             vanillaRemappedSpigotJar.set(removeSpigotExcludes.flatMap { it.outputZip })
-            spigotApiDeps.set(downloadSpigotDependencies.flatMap { it.apiOutputDir })
-            spigotServerDeps.set(downloadSpigotDependencies.flatMap { it.serverOutputDir })
+            spigotDeps.set(downloadSpigotDependencies.flatMap { it.outputDir })
             constructors.set(initialTasks.extractMcp.flatMap { it.constructors })
         }
 

src/main/kotlin/tasks/AddMissingSpigotClassMappings.kt

@@ -25,12 +25,12 @@ package io.papermc.paperweight.tasks
 import io.papermc.paperweight.util.defaultOutput
 import io.papermc.paperweight.util.file
 import io.papermc.paperweight.util.fileOrNull
+import java.io.File
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.Optional
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.io.File
 
 abstract class AddMissingSpigotClassMappings : BaseTask() {
 

src/main/kotlin/tasks/ApplyDiffPatches.kt

@@ -28,6 +28,10 @@ import io.papermc.paperweight.util.Git
 import io.papermc.paperweight.util.UselessOutputStream
 import io.papermc.paperweight.util.ensureParentExists
 import io.papermc.paperweight.util.file
+import java.net.URI
+import java.nio.file.FileSystems
+import java.nio.file.Files
+import java.util.Date
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.provider.Property
@@ -36,10 +40,6 @@ import org.gradle.api.tasks.InputDirectory
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputDirectory
 import org.gradle.api.tasks.TaskAction
-import java.net.URI
-import java.nio.file.FileSystems
-import java.nio.file.Files
-import java.util.Date
 
 abstract class ApplyDiffPatches : ControllableOutputTask() {
 

src/main/kotlin/tasks/ApplyGitPatches.kt

@@ -25,6 +25,7 @@ package io.papermc.paperweight.tasks
 import io.papermc.paperweight.PaperweightException
 import io.papermc.paperweight.util.Git
 import io.papermc.paperweight.util.file
+import java.io.File
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.provider.Property
 import org.gradle.api.tasks.Input
@@ -32,7 +33,6 @@ import org.gradle.api.tasks.InputDirectory
 import org.gradle.api.tasks.OutputDirectory
 import org.gradle.api.tasks.TaskAction
 import org.gradle.internal.os.OperatingSystem
-import java.io.File
 
 abstract class ApplyGitPatches : ControllableOutputTask() {
 

src/main/kotlin/tasks/ApplyMcpPatches.kt

@@ -23,11 +23,11 @@
 package io.papermc.paperweight.tasks
 
 import io.papermc.paperweight.util.Git
+import java.io.File
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputDirectory
 import org.gradle.api.tasks.InputFile
-import java.io.File
 
 abstract class ApplyMcpPatches : ZippedTask() {
 

src/main/kotlin/tasks/ApplySourceAt.kt

@@ -22,13 +22,19 @@
 
 package io.papermc.paperweight.tasks
 
+import io.papermc.paperweight.util.file
 import io.papermc.paperweight.util.path
+import java.io.File
+import javax.inject.Inject
 import org.cadixdev.at.io.AccessTransformFormats
 import org.cadixdev.mercury.Mercury
 import org.cadixdev.mercury.at.AccessTransformerRewriter
 import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.provider.ListProperty
 import org.gradle.api.tasks.InputFile
-import java.io.File
+import org.gradle.workers.WorkAction
+import org.gradle.workers.WorkParameters
+import org.gradle.workers.WorkerExecutor
 
 abstract class ApplySourceAt : ZippedTask() {
 
@@ -39,43 +45,70 @@ abstract class ApplySourceAt : ZippedTask() {
     @get:InputFile
     abstract val atFile: RegularFileProperty
 
+    @get:Inject
+    abstract val workerExecutor: WorkerExecutor
+
     override fun run(rootDir: File) {
-        val inputDir = rootDir.resolve("input")
-        val outputDir = rootDir.resolve("output")
+        val input = rootDir.resolve("input")
+        val output = rootDir.resolve("output")
 
         // Move everything into `input/` so we can put output into `output/`
-        inputDir.mkdirs()
+        input.mkdirs()
         rootDir.listFiles()?.forEach { file ->
-            if (file != inputDir) {
-                file.renameTo(inputDir.resolve(file.name))
+            if (file != input) {
+                file.renameTo(input.resolve(file.name))
             }
         }
-        outputDir.mkdirs()
+        output.mkdirs()
 
-        val at = AccessTransformFormats.FML.read(atFile.path)
-
-        Mercury().let { merc ->
-            merc.classPath.addAll(listOf(
-                vanillaJar.path,
-                vanillaRemappedSrgJar.path
-            ))
-
-            merc.processors.add(AccessTransformerRewriter.create(at))
-
-            merc.rewrite(inputDir.toPath(), outputDir.toPath())
+        val queue = workerExecutor.processIsolation {
+            forkOptions.jvmArgs("-Xmx2G")
         }
 
+        queue.submit(AtAction::class.java) {
+            classpath.add(vanillaJar.file)
+            classpath.add(vanillaRemappedSrgJar.file)
+
+            at.set(atFile.file)
+
+            inputDir.set(input)
+            outputDir.set(output)
+        }
+
+        queue.await()
+
         // Remove input files
         rootDir.listFiles()?.forEach { file ->
-            if (file != outputDir) {
+            if (file != output) {
                 file.deleteRecursively()
             }
         }
 
         // Move output into root
-        outputDir.listFiles()?.forEach { file ->
+        output.listFiles()?.forEach { file ->
             file.renameTo(rootDir.resolve(file.name))
         }
-        outputDir.delete()
+        output.delete()
+    }
+
+    abstract class AtAction : WorkAction<AtParams> {
+        override fun execute() {
+            val at = AccessTransformFormats.FML.read(parameters.at.path)
+
+            Mercury().let { merc ->
+                merc.classPath.addAll(parameters.classpath.get().map { it.toPath() })
+
+                merc.processors.add(AccessTransformerRewriter.create(at))
+
+                merc.rewrite(parameters.inputDir.path, parameters.outputDir.path)
+            }
+        }
+    }
+
+    interface AtParams : WorkParameters {
+        val classpath: ListProperty<File>
+        val at: RegularFileProperty
+        val inputDir: RegularFileProperty
+        val outputDir: RegularFileProperty
     }
 }

src/main/kotlin/tasks/BaseTask.kt

@@ -22,12 +22,12 @@
 
 package io.papermc.paperweight.tasks
 
+import javax.inject.Inject
 import org.gradle.api.DefaultTask
 import org.gradle.api.file.ArchiveOperations
 import org.gradle.api.file.FileSystemOperations
 import org.gradle.api.file.ProjectLayout
 import org.gradle.api.model.ObjectFactory
-import javax.inject.Inject
 
 abstract class BaseTask : DefaultTask() {
 

src/main/kotlin/tasks/DecompileVanillaJar.kt

@@ -28,13 +28,13 @@ import io.papermc.paperweight.util.cache
 import io.papermc.paperweight.util.defaultOutput
 import io.papermc.paperweight.util.ensureDeleted
 import io.papermc.paperweight.util.runJar
+import java.util.concurrent.ThreadLocalRandom
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.provider.Property
 import org.gradle.api.tasks.Input
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.util.concurrent.ThreadLocalRandom
 
 abstract class DecompileVanillaJar : BaseTask() {
 

src/main/kotlin/tasks/DownloadServerJar.kt

@@ -25,13 +25,13 @@ package io.papermc.paperweight.tasks
 import io.papermc.paperweight.PaperweightException
 import io.papermc.paperweight.util.defaultOutput
 import io.papermc.paperweight.util.download
+import java.math.BigInteger
+import java.security.MessageDigest
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.provider.Property
 import org.gradle.api.tasks.Input
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.math.BigInteger
-import java.security.MessageDigest
 
 abstract class DownloadServerJar : BaseTask() {
 

src/main/kotlin/tasks/FilterExcludes.kt

@@ -23,9 +23,9 @@
 package io.papermc.paperweight.tasks
 
 import io.papermc.paperweight.util.file
+import java.io.File
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
-import java.io.File
 
 /**
  * Because Spigot doesn't remap all classes, there are class and package name clashes if we don't do this in the source

src/main/kotlin/tasks/PatchMcpCsv.kt

@@ -22,13 +22,13 @@
 
 package io.papermc.paperweight.tasks
 
+import java.io.PrintWriter
+import java.util.regex.Pattern
 import org.gradle.api.DefaultTask
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.io.PrintWriter
-import java.util.regex.Pattern
 
 abstract class PatchMcpCsv : DefaultTask() {
 

src/main/kotlin/tasks/RemapSpigotAt.kt

@@ -24,6 +24,7 @@ package io.papermc.paperweight.tasks
 
 import io.papermc.paperweight.util.defaultOutput
 import io.papermc.paperweight.util.file
+import java.util.jar.JarFile
 import org.cadixdev.at.AccessChange
 import org.cadixdev.at.AccessTransform
 import org.cadixdev.at.AccessTransformSet
@@ -36,7 +37,6 @@ import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.util.jar.JarFile
 
 abstract class RemapSpigotAt : BaseTask() {
 

src/main/kotlin/tasks/RemapSrgSources.kt

@@ -24,12 +24,12 @@ package io.papermc.paperweight.tasks
 
 import io.papermc.paperweight.PaperweightException
 import io.papermc.paperweight.util.getCsvReader
-import org.gradle.api.file.RegularFileProperty
-import org.gradle.api.tasks.InputFile
 import java.io.BufferedReader
 import java.io.BufferedWriter
 import java.io.File
 import java.util.regex.Pattern
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputFile
 
 abstract class RemapSrgSources : ZippedTask() {
 

src/main/kotlin/tasks/WriteLibrariesFile.kt

@@ -51,7 +51,9 @@ abstract class WriteLibrariesFile : BaseTask() {
         outputFile.file.delete()
         outputFile.file.bufferedWriter().use { writer ->
             for (file in files) {
-                writer.appendln("-e=${file.absolutePath}")
+                if (file.name.endsWith(".jar")) {
+                    writer.appendln("-e=${file.absolutePath}")
+                }
             }
         }
     }

src/main/kotlin/tasks/ZippedTask.kt

@@ -28,13 +28,13 @@ import io.papermc.paperweight.util.file
 import io.papermc.paperweight.util.fileOrNull
 import io.papermc.paperweight.util.unzip
 import io.papermc.paperweight.util.zip
+import java.io.File
+import java.util.concurrent.ThreadLocalRandom
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.Optional
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.io.File
-import java.util.concurrent.ThreadLocalRandom
 
 abstract class ZippedTask : BaseTask() {
 

src/main/kotlin/tasks/download-task.kt

@@ -32,6 +32,9 @@ import io.papermc.paperweight.util.fromJson
 import io.papermc.paperweight.util.gson
 import io.papermc.paperweight.util.mcinject
 import io.papermc.paperweight.util.rename
+import java.io.File
+import javax.inject.Inject
+import javax.xml.parsers.DocumentBuilderFactory
 import org.gradle.api.DefaultTask
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.ProjectLayout
@@ -47,9 +50,6 @@ import org.gradle.workers.WorkAction
 import org.gradle.workers.WorkParameters
 import org.gradle.workers.WorkerExecutor
 import org.w3c.dom.Element
-import java.io.File
-import javax.inject.Inject
-import javax.xml.parsers.DocumentBuilderFactory
 
 abstract class DownloadTask : DefaultTask() {
 
@@ -182,9 +182,7 @@ abstract class DownloadSpigotDependencies : BaseTask() {
     abstract val serverPom: RegularFileProperty
 
     @get:OutputDirectory
-    abstract val apiOutputDir: DirectoryProperty
-    @get:OutputDirectory
-    abstract val serverOutputDir: DirectoryProperty
+    abstract val outputDir: DirectoryProperty
 
     @get:Inject
     abstract val workerExecutor: WorkerExecutor
@@ -194,26 +192,23 @@ abstract class DownloadSpigotDependencies : BaseTask() {
         val apiSetup = parsePom(apiPom.file)
         val serverSetup = parsePom(serverPom.file)
 
-        val apiOut = apiOutputDir.file
-        apiOut.deleteRecursively()
+        val out = outputDir.file
+        out.deleteRecursively()
 
-        val serverOut = serverOutputDir.file
-        serverOut.deleteRecursively()
+        val spigotRepos = mutableSetOf<String>()
+        spigotRepos += apiSetup.repos
+        spigotRepos += serverSetup.repos
+
+        val artifacts = mutableSetOf<MavenArtifact>()
+        artifacts += apiSetup.artifacts
+        artifacts += serverSetup.artifacts
 
         val queue = workerExecutor.noIsolation()
-        for (art in apiSetup.artifacts) {
+        for (art in artifacts) {
             queue.submit(DownloadWorker::class.java) {
-                repos.set(apiSetup.repos)
+                repos.set(spigotRepos)
                 artifact.set(art.toString())
-                target.set(apiOut)
-                downloadToDir.set(true)
-            }
-        }
-        for (art in serverSetup.artifacts) {
-            queue.submit(DownloadWorker::class.java) {
-                repos.set(serverSetup.repos)
-                artifact.set(art.toString())
-                target.set(serverOut)
+                target.set(out)
                 downloadToDir.set(true)
             }
         }

src/main/kotlin/tasks/extract-tasks.kt

@@ -26,13 +26,13 @@ import io.papermc.paperweight.util.McpConfig
 import io.papermc.paperweight.util.file
 import io.papermc.paperweight.util.fromJson
 import io.papermc.paperweight.util.gson
+import java.io.File
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputDirectory
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
-import java.io.File
 
 abstract class Extract : BaseTask() {
 

src/main/kotlin/tasks/patchremap/PatchSourceRemapWorker.kt

@@ -26,11 +26,11 @@ import io.papermc.paperweight.tasks.sourceremap.ConstructorsData
 import io.papermc.paperweight.tasks.sourceremap.ParamNames
 import io.papermc.paperweight.tasks.sourceremap.PatchParameterRemapper
 import io.papermc.paperweight.tasks.sourceremap.SrgParameterRemapper
+import java.nio.file.Files
+import java.nio.file.Path
 import org.cadixdev.lorenz.MappingSet
 import org.cadixdev.mercury.Mercury
 import org.cadixdev.mercury.remapper.MercuryRemapper
-import java.nio.file.Files
-import java.nio.file.Path
 
 class PatchSourceRemapWorker(
     private val mappings: MappingSet,

src/main/kotlin/tasks/patchremap/RemapPatches.kt

@@ -28,6 +28,8 @@ import io.papermc.paperweight.tasks.sourceremap.parseParamNames
 import io.papermc.paperweight.util.Git
 import io.papermc.paperweight.util.cache
 import io.papermc.paperweight.util.file
+import java.io.File
+import java.util.zip.ZipFile
 import org.cadixdev.lorenz.io.MappingFormats
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.RegularFile
@@ -39,8 +41,6 @@ import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputDirectory
 import org.gradle.api.tasks.TaskAction
 import org.gradle.kotlin.dsl.get
-import java.io.File
-import java.util.zip.ZipFile
 
 abstract class RemapPatches : BaseTask() {
 

src/main/kotlin/tasks/sourceremap/RemapSources.kt

@@ -26,6 +26,8 @@ import io.papermc.paperweight.tasks.ZippedTask
 import io.papermc.paperweight.util.defaultOutput
 import io.papermc.paperweight.util.file
 import io.papermc.paperweight.util.path
+import java.io.File
+import javax.inject.Inject
 import org.cadixdev.at.AccessTransformSet
 import org.cadixdev.at.io.AccessTransformFormats
 import org.cadixdev.lorenz.io.MappingFormats
@@ -36,10 +38,13 @@ import org.cadixdev.mercury.extra.BridgeMethodRewriter
 import org.cadixdev.mercury.remapper.MercuryRemapper
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.provider.ListProperty
 import org.gradle.api.tasks.InputDirectory
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.OutputFile
-import java.io.File
+import org.gradle.workers.WorkAction
+import org.gradle.workers.WorkParameters
+import org.gradle.workers.WorkerExecutor
 
 abstract class RemapSources : ZippedTask() {
 
@@ -51,9 +56,7 @@ abstract class RemapSources : ZippedTask() {
     abstract val mappings: RegularFileProperty
 
     @get:InputDirectory
-    abstract val spigotApiDeps: DirectoryProperty
-    @get:InputDirectory
-    abstract val spigotServerDeps: DirectoryProperty
+    abstract val spigotDeps: DirectoryProperty
 
     @get:InputFile
     abstract val constructors: RegularFileProperty
@@ -67,6 +70,9 @@ abstract class RemapSources : ZippedTask() {
     @get:OutputFile
     abstract val parameterNames: RegularFileProperty
 
+    @get:Inject
+    abstract val workerExecutor: WorkerExecutor
+
     override fun init() {
         super.init()
         generatedAt.convention(defaultOutput("at"))
@@ -74,41 +80,71 @@ abstract class RemapSources : ZippedTask() {
     }
 
     override fun run(rootDir: File) {
-        val constructorsData = parseConstructors(constructors.file)
-
-        val paramNames: ParamNames = newParamNames()
-
         val srcDir = spigotServerDir.file.resolve("src/main/java")
 
-        val mappingSet = MappingFormats.TSRG.read(mappings.path)
-        val processAt = AccessTransformSet.create()
-
-        // Remap any references Spigot maps to SRG
-        Mercury().let { merc ->
-            merc.classPath.addAll(listOf(
-                vanillaJar.path,
-                vanillaRemappedSpigotJar.path,
-                spigotApiDir.path.resolve("src/main/java"),
-                *spigotApiDeps.get().asFileTree.files.map { it.toPath() }.toTypedArray(),
-                *spigotServerDeps.get().asFileTree.files.map { it.toPath() }.toTypedArray()
-            ))
-
-            merc.processors += AccessAnalyzerProcessor.create(processAt, mappingSet)
-
-            merc.process(srcDir.toPath())
-
-            merc.processors.clear()
-            merc.processors.addAll(listOf(
-                MercuryRemapper.create(mappingSet),
-                BridgeMethodRewriter.create(),
-                AccessTransformerRewriter.create(processAt),
-                SrgParameterRemapper(mappingSet, constructorsData, paramNames)
-            ))
-
-            merc.rewrite(srcDir.toPath(), rootDir.toPath())
+        val queue = workerExecutor.processIsolation {
+            forkOptions.jvmArgs("-Xmx2G")
         }
 
-        AccessTransformFormats.FML.write(generatedAt.path, processAt)
-        writeParamNames(paramNames, parameterNames.file)
+        queue.submit(RemapAction::class.java) {
+            classpath.add(vanillaJar.file)
+            classpath.add(vanillaRemappedSpigotJar.file)
+            classpath.add(spigotApiDir.dir("src/main/java").get().asFile)
+            classpath.addAll(spigotDeps.get().asFileTree.filter { it.name.endsWith(".jar") }.files)
+
+            mappings.set(this@RemapSources.mappings.file)
+            constructors.set(this@RemapSources.constructors.file)
+            inputDir.set(srcDir)
+
+            outputDir.set(rootDir)
+            generatedAtOutput.set(generatedAt.file)
+            paramNamesOutput.set(parameterNames.file)
+        }
+
+        queue.await()
+    }
+
+    abstract class RemapAction : WorkAction<RemapParams> {
+        override fun execute() {
+            val mappingSet = MappingFormats.TSRG.read(parameters.mappings.path)
+            val processAt = AccessTransformSet.create()
+
+            val constructorsData = parseConstructors(parameters.constructors.file)
+
+            val paramNames: ParamNames = newParamNames()
+
+            // Remap any references Spigot maps to SRG
+            Mercury().let { merc ->
+                merc.classPath.addAll(parameters.classpath.get().map { it.toPath() })
+
+                merc.processors += AccessAnalyzerProcessor.create(processAt, mappingSet)
+
+                merc.process(parameters.inputDir.path)
+
+                merc.processors.clear()
+                merc.processors.addAll(listOf(
+                    MercuryRemapper.create(mappingSet),
+                    BridgeMethodRewriter.create(),
+                    AccessTransformerRewriter.create(processAt),
+                    SrgParameterRemapper(mappingSet, constructorsData, paramNames)
+                ))
+
+                merc.rewrite(parameters.inputDir.path, parameters.outputDir.path)
+            }
+
+            AccessTransformFormats.FML.write(parameters.generatedAtOutput.path, processAt)
+            writeParamNames(paramNames, parameters.paramNamesOutput.file)
+        }
+    }
+
+    interface RemapParams : WorkParameters {
+        val classpath: ListProperty<File>
+        val mappings: RegularFileProperty
+        val constructors: RegularFileProperty
+        val inputDir: RegularFileProperty
+
+        val generatedAtOutput: RegularFileProperty
+        val outputDir: RegularFileProperty
+        val paramNamesOutput: RegularFileProperty
     }
 }

src/main/kotlin/util/Constants.kt

@@ -38,9 +38,7 @@ object Constants {
     const val MINECRAFT_JARS_PATH = "$JARS_PATH/minecraft"
     const val MCP_TOOLS_PATH = "$JARS_PATH/tools"
     const val MCP_ZIPS_PATH = "$JARS_PATH/mcp"
-    private const val SPIGOT_JARS_PATH = "$JARS_PATH/spigot"
-    const val SPIGOT_API_JARS_PATH = "$SPIGOT_JARS_PATH/api"
-    const val SPIGOT_SERVER_JARS_PATH = "$SPIGOT_JARS_PATH/server"
+    const val SPIGOT_JARS_PATH = "$JARS_PATH/spigot"
 
     const val MCP_DATA_DIR = "mcp/data"
     const val MCP_MAPPINGS_DIR = "mcp/mappings"

src/main/kotlin/util/MavenArtifact.kt

@@ -25,7 +25,7 @@ package io.papermc.paperweight.util
 import io.papermc.paperweight.PaperweightException
 import java.io.File
 
-class MavenArtifact(
+data class MavenArtifact(
     private val group: String,
     private val artifact: String,
     private val version: String,

src/main/kotlin/util/download.kt

@@ -23,6 +23,12 @@
 package io.papermc.paperweight.util
 
 import io.papermc.paperweight.PaperweightException
+import java.io.File
+import java.net.URI
+import java.net.URL
+import java.time.Instant
+import java.time.format.DateTimeFormatter
+import java.util.concurrent.TimeUnit
 import org.apache.http.HttpHost
 import org.apache.http.HttpStatus
 import org.apache.http.client.config.CookieSpecs
@@ -32,11 +38,6 @@ import org.apache.http.client.methods.HttpGet
 import org.apache.http.client.utils.DateUtils
 import org.apache.http.impl.client.HttpClientBuilder
 import org.gradle.api.provider.Provider
-import java.io.File
-import java.net.URI
-import java.net.URL
-import java.util.Date
-import java.util.concurrent.TimeUnit
 
 fun download(source: Any, target: Any) {
     val url = source.convertToUrl()
@@ -72,7 +73,8 @@ private fun download(source: URL, target: File) {
             .build()
 
         if (time > 0) {
-            httpGet.setHeader("If-Modified-Since", DateUtils.formatDate(Date(time)))
+            val value = DateTimeFormatter.RFC_1123_DATE_TIME.format(Instant.ofEpochMilli(time))
+            httpGet.setHeader("If-Modified-Since", value)
         }
         if (etag != null) {
             httpGet.setHeader("If-None-Match", etag)

src/main/kotlin/util/jvm.kt

@@ -23,8 +23,8 @@
 package io.papermc.paperweight.util
 
 import io.papermc.paperweight.PaperweightException
-import org.gradle.internal.jvm.Jvm
 import java.io.OutputStream
+import org.gradle.internal.jvm.Jvm
 
 fun runJar(jar: Any, workingDir: Any, logFile: Any?, jvmArgs: List<String> = listOf(), vararg args: String) {
     val jarFile = jar.convertToFile()

src/main/kotlin/util/utils.kt

@@ -30,6 +30,13 @@ import io.papermc.paperweight.PaperweightException
 import io.papermc.paperweight.ext.PaperweightExtension
 import io.papermc.paperweight.tasks.BaseTask
 import io.papermc.paperweight.util.Constants.paperTaskOutput
+import java.io.File
+import java.io.InputStream
+import java.io.OutputStream
+import java.nio.file.Path
+import java.util.Optional
+import kotlin.reflect.KClass
+import kotlin.reflect.KProperty
 import org.cadixdev.lorenz.MappingSet
 import org.cadixdev.lorenz.io.TextMappingFormat
 import org.gradle.api.Project
@@ -41,13 +48,6 @@ import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.TaskContainer
 import org.gradle.api.tasks.TaskProvider
-import java.io.File
-import java.io.InputStream
-import java.io.OutputStream
-import java.nio.file.Path
-import java.util.Optional
-import kotlin.reflect.KClass
-import kotlin.reflect.KProperty
 
 val gson: Gson = Gson()