Starting to put the launch itself together

src/main/java/net/minecraftforge/fml/loading/FMLCommonLaunchHandler.java

@@ -0,0 +1,30 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2018.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.fml.loading;
+
+import cpw.mods.modlauncher.api.IEnvironment;
+
+public abstract class FMLCommonLaunchHandler
+{
+    public void setup(final IEnvironment environment)
+    {
+        // We need to check for deobf and patched jar here and if not, build one.
+    }
+}

src/main/java/net/minecraftforge/fml/loading/FMLDevLaunchProvider.java

@@ -19,6 +19,7 @@
 
 package net.minecraftforge.fml.loading;
 
+import cpw.mods.modlauncher.api.IEnvironment;
 import cpw.mods.modlauncher.api.ILaunchHandlerService;
 import net.minecraft.client.main.Main;
 
@@ -27,7 +28,10 @@ import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.concurrent.Callable;
 
-public class FMLDevLaunchProvider implements ILaunchHandlerService
+import static net.minecraftforge.fml.Logging.CORE;
+import static net.minecraftforge.fml.Logging.fmlLog;
+
+public class FMLDevLaunchProvider extends FMLCommonLaunchHandler implements ILaunchHandlerService
 {
     @Override
     public String name()
@@ -58,4 +62,10 @@ public class FMLDevLaunchProvider implements ILaunchHandlerService
             return null;
         };
     }
+
+    @Override
+    public void setup(IEnvironment environment)
+    {
+        fmlLog.debug(CORE, "No jar creation necessary. Launch is dev environment");
+    }
 }

src/main/java/net/minecraftforge/fml/loading/FMLLaunchProvider.java

@@ -25,7 +25,7 @@ import net.minecraft.client.main.Main;
 import java.nio.file.Path;
 import java.util.concurrent.Callable;
 
-public class FMLLaunchProvider implements ILaunchHandlerService
+public class FMLLaunchProvider extends FMLCommonLaunchHandler implements ILaunchHandlerService
 {
     @Override
     public String name()

src/main/java/net/minecraftforge/fml/loading/FMLLoader.java

@@ -20,6 +20,7 @@
 package net.minecraftforge.fml.loading;
 
 import cpw.mods.modlauncher.api.IEnvironment;
+import cpw.mods.modlauncher.api.ILaunchHandlerService;
 import cpw.mods.modlauncher.api.ITransformationService;
 import cpw.mods.modlauncher.api.IncompatibleEnvironmentException;
 import cpw.mods.modlauncher.serviceapi.ILaunchPluginService;
@@ -89,6 +90,24 @@ public class FMLLoader
         languageLoadingProvider = new LanguageLoadingProvider();
     }
 
+    static void setupLaunchHandler(final IEnvironment environment) throws IncompatibleEnvironmentException
+    {
+        final String launchTarget = environment.getProperty(IEnvironment.Keys.LAUNCHTARGET.get()).orElse("MISSING");
+        final Optional<ILaunchHandlerService> launchHandler = environment.findLaunchHandler(launchTarget);
+        fmlLog.debug(CORE, "Using {} as launch service", launchTarget);
+        if (!launchHandler.isPresent()) {
+            fmlLog.error(CORE,"Missing LaunchHandler {}, cannot continue", launchTarget);
+            throw new IncompatibleEnvironmentException("Missing launch handler");
+        }
+
+        if (!(launchHandler.get() instanceof FMLCommonLaunchHandler)) {
+            fmlLog.error(CORE, "Incompatible Launch handler found - type {}, cannot continue", launchHandler.get().getClass().getName());
+            throw new IncompatibleEnvironmentException("Incompatible launch handler found");
+        }
+
+        FMLCommonLaunchHandler commonLaunchHandler = (FMLCommonLaunchHandler)launchHandler.get();
+        commonLaunchHandler.setup(environment);
+    }
     public static void beginModScan()
     {
         fmlLog.debug(SCAN,"Scanning for Mod Locators");

src/main/java/net/minecraftforge/fml/loading/FMLServiceProvider.java

@@ -20,6 +20,7 @@
 package net.minecraftforge.fml.loading;
 
 import cpw.mods.modlauncher.api.IEnvironment;
+import cpw.mods.modlauncher.api.ILaunchHandlerService;
 import cpw.mods.modlauncher.api.ITransformationService;
 import cpw.mods.modlauncher.api.ITransformer;
 import cpw.mods.modlauncher.api.IncompatibleEnvironmentException;
@@ -31,6 +32,7 @@ import net.minecraftforge.fml.common.FMLPaths;
 import javax.annotation.Nonnull;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.BiFunction;