Hide existing Minecraft JARs from getResources, and change exception …

…class

build.gradle

@@ -13,7 +13,7 @@ apply plugin: 'net.minecraftforge.gradle'
 apply plugin: 'eclipse'
 apply plugin: 'maven-publish'
 
-version = '1.0.7'
+version = '1.0.8'
 group = 'link.infra.jumploader' // http://maven.apache.org/guides/mini/guide-naming-conventions.html
 archivesBaseName = 'jumploader'
 

gradle.properties

@@ -1,3 +1,3 @@
 modGroup=link.infra.jumploader
-modVersion=1.0.7
+modVersion=1.0.8
 modBaseName=jumploader

src/main/java/link/infra/jumploader/Jumploader.java

@@ -35,7 +35,7 @@
 import java.util.Set;
 
 public class Jumploader implements ITransformationService {
-	public static final String VERSION = "1.0.7";
+	public static final String VERSION = "1.0.8";
 	public static final String USER_AGENT = "Jumploader/" + VERSION;
 
 	private final Logger LOGGER = LogManager.getLogger();
@@ -184,7 +184,7 @@ public void onLoad(@Nonnull IEnvironment env, @Nonnull Set<String> set) {
 			Thread.currentThread().setUncaughtExceptionHandler((t, e) -> {
 				// Do nothing!
 			});
-			throw new RuntimeException("Closing main thread, not an exception!"){
+			throw new ThreadCloseException("Jumploader is closing the main thread, not an error!"){
 				@Override
 				public void printStackTrace(PrintStream s) {
 					// Do nothing!
@@ -199,6 +199,12 @@ public void printStackTrace(PrintWriter s) {
 		System.exit(1);
 	}
 
+	private static class ThreadCloseException extends RuntimeException {
+		public ThreadCloseException(String reason) {
+			super(reason);
+		}
+	}
+
 	private List<URL> resolveJars(ConfigFile config, ParsedArguments argsParsed) {
 		List<ResolvableJar> configuredJars = config.getConfiguredJars();
 		List<ResolvableJar> downloadRequiredJars = new ArrayList<>();

src/main/java/link/infra/jumploader/JumploaderClassLoader.java

@@ -3,6 +3,7 @@
 import link.infra.jumploader.specialcases.ClassBlacklist;
 import link.infra.jumploader.specialcases.ClassRedefiner;
 import link.infra.jumploader.specialcases.SpecialCaseHandler;
+import link.infra.jumploader.specialcases.URLBlacklist;
 
 import java.io.IOException;
 import java.net.URL;
@@ -14,19 +15,23 @@
 class JumploaderClassLoader extends URLClassLoader {
 	private final List<ClassBlacklist> blacklists;
 	private final List<ClassRedefiner> classRedefiners;
+	private final List<URLBlacklist> urlBlacklists;
 	private final ClassLoader parent = JumploaderClassLoader.class.getClassLoader();
 
 	public JumploaderClassLoader(URL[] urls, SpecialCaseHandler specialCaseHandler) {
 		super(urls, JumploaderClassLoader.class.getClassLoader());
 		this.blacklists = specialCaseHandler.getImplementingCases(ClassBlacklist.class);
 		this.classRedefiners = specialCaseHandler.getImplementingCases(ClassRedefiner.class);
+		this.urlBlacklists = specialCaseHandler.getImplementingCases(URLBlacklist.class);
 	}
 
 	@Override
 	public Enumeration<URL> getResources(String name) throws IOException {
 		// Prioritise self over parent classloader
 		List<URL> urls = Collections.list(findResources(name));
 		urls.addAll(Collections.list(parent.getResources(name)));
+		// Hide blacklisted URLs, as fabric API looks at the back of the list anyway
+		urls.removeIf(u -> urlBlacklists.stream().filter(b -> b.shouldBlacklistUrl(u)).limit(1).count() > 0);
 		return Collections.enumeration(urls);
 	}
 
@@ -37,6 +42,7 @@ public URL getResource(String name) {
 		if (url != null) {
 			return url;
 		}
+		// TODO: use the blacklist in getResource as well?
 		return parent.getResource(name);
 	}
 

src/main/java/link/infra/jumploader/specialcases/ForgeJarClasspathModifier.java

@@ -3,11 +3,20 @@
 import link.infra.jumploader.resources.ParsedArguments;
 import link.infra.jumploader.util.ClasspathUtil;
 
+import java.io.IOException;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.Arrays;
 import java.util.List;
+import java.util.Set;
+
+public class ForgeJarClasspathModifier implements ClasspathModifier, URLBlacklist {
+	private Set<Path> blacklistedPaths;
 
-public class ForgeJarClasspathModifier implements ClasspathModifier {
 	@Override
 	public boolean shouldApply(List<URL> loadedJars, String mainClass, ParsedArguments gameArguments) {
 		// Always applies - if you're having problems this you should probably load the
@@ -18,6 +27,28 @@ public boolean shouldApply(List<URL> loadedJars, String mainClass, ParsedArgumen
 	@Override
 	public void modifyClasspath() {
 		// If a JAR contains the Minecraft Main classes, remove it from the classpath - so Fabric doesn't see it and think the remapper needs to use it
-		ClasspathUtil.removeMatchingClasses(Arrays.asList("net.minecraft.client.main.Main", "net.minecraft.server.MinecraftServer"));
+		blacklistedPaths = ClasspathUtil.removeMatchingClasses(Arrays.asList("net.minecraft.client.main.Main", "net.minecraft.server.MinecraftServer"));
+	}
+
+	@Override
+	public boolean shouldBlacklistUrl(URL url) {
+		String[] splitUrl = url.getPath().split("!");
+		if (splitUrl.length != 2) {
+			return false;
+		}
+		Path resPath;
+		try {
+			resPath = Paths.get(new URI(splitUrl[0]));
+		} catch (URISyntaxException e) {
+			return false;
+		}
+		for (Path blacklistedPath : blacklistedPaths) {
+			try {
+				if (Files.isSameFile(resPath, blacklistedPath)) {
+					return true;
+				}
+			} catch (IOException ignored) {}
+		}
+		return false;
 	}
 }

src/main/java/link/infra/jumploader/specialcases/URLBlacklist.java

@@ -0,0 +1,7 @@
+package link.infra.jumploader.specialcases;
+
+import java.net.URL;
+
+public interface URLBlacklist extends SpecialCase {
+	boolean shouldBlacklistUrl(URL url);
+}

src/main/java/link/infra/jumploader/util/ClasspathUtil.java

@@ -11,8 +11,9 @@
 public class ClasspathUtil {
 	private ClasspathUtil() {}
 
-	public static void removeMatchingClasses(List<String> classesToTest) {
+	public static Set<Path> removeMatchingClasses(List<String> classesToTest) {
 		List<String> classPath = new ArrayList<>(Arrays.asList(System.getProperty("java.class.path").split(File.pathSeparator)));
+		Set<Path> blacklistedJars = new HashSet<>();
 
 		ClassLoader throwawayClassLoader = new ClassLoader() {};
 		Set<Path> sources = new HashSet<>();
@@ -28,6 +29,7 @@ public static void removeMatchingClasses(List<String> classesToTest) {
 		while (iter.hasNext()) {
 			String currentJar = iter.next();
 			for (Path matchingSourcePath : sources) {
+				blacklistedJars.add(matchingSourcePath);
 				try {
 					if (Files.isSameFile(Paths.get(currentJar), matchingSourcePath)) {
 						iter.remove();
@@ -37,5 +39,6 @@ public static void removeMatchingClasses(List<String> classesToTest) {
 			}
 		}
 		System.setProperty("java.class.path", String.join(File.pathSeparator, classPath));
+		return blacklistedJars;
 	}
 }

src/main/resources/fabric.mod.json

@@ -1,7 +1,7 @@
 {
   "schemaVersion": 1,
   "id": "jumploader",
-  "version": "1.0.7",
+  "version": "1.0.8",
 
   "name": "Jumploader",
   "description": "Allows the use of Fabric mods in Twitch modpacks, by loading Fabric as if it were a Forge mod.",