diff --git a/Launcher/Launcher.iml b/Launcher/Launcher.iml
index 1c93b9c..1d2bccf 100644
--- a/Launcher/Launcher.iml
+++ b/Launcher/Launcher.iml
@@ -8,7 +8,7 @@
       <sourceFolder url="file://$MODULE_DIR$/source-authlib" isTestSource="false" packagePrefix="com.mojang.authlib" />
       <excludeFolder url="file://$MODULE_DIR$/runtime" />
     </content>
-    <orderEntry type="jdk" jdkName="1.8" jdkType="JavaSDK" />
+    <orderEntry type="inheritedJdk" />
     <orderEntry type="module-library" scope="PROVIDED">
       <library>
         <CLASSES>
diff --git a/Launcher/source/client/ClientLauncher.java b/Launcher/source/client/ClientLauncher.java
index 3a28232..a1cd310 100644
--- a/Launcher/source/client/ClientLauncher.java
+++ b/Launcher/source/client/ClientLauncher.java
@@ -175,7 +175,7 @@
         // Verify ClientLauncher sign and classpath
         LogHelper.debug("Verifying ClientLauncher sign and classpath");
         SecurityHelper.verifySign(LauncherRequest.BINARY_PATH, params.launcherSign, publicKey);
-        URL[] classpath = JVMHelper.LOADER.getURLs();
+        URL[] classpath = JVMHelper.getClassPath();
         for (URL classpathURL : classpath) {
             Path file = Paths.get(classpathURL.toURI());
             if (!file.startsWith(IOHelper.JVM_DIR) && !file.equals(LauncherRequest.BINARY_PATH)) {
@@ -306,7 +306,7 @@
         // Add client classpath
         URL[] classPath = resolveClassPath(params.clientDir, profile.getClassPath());
         for (URL url : classPath) {
-            JVMHelper.UCP.addURL(url);
+            JVMHelper.addClassPath(url);
         }
 
         // Resolve main class and method
diff --git a/Launcher/source/helper/JVMHelper.java b/Launcher/source/helper/JVMHelper.java
index 1d15ae7..8996b5b 100644
--- a/Launcher/source/helper/JVMHelper.java
+++ b/Launcher/source/helper/JVMHelper.java
@@ -6,13 +6,13 @@
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
-import java.net.URLClassLoader;
+import java.net.URL;
 import java.nio.file.Path;
+import java.security.cert.Certificate;
 import java.util.Locale;
 
 import com.sun.management.OperatingSystemMXBean;
 import launcher.LauncherAPI;
-import sun.misc.URLClassPath;
 
 public final class JVMHelper {
     // MXBeans exports
@@ -29,18 +29,31 @@
 
     // Public static fields
     @LauncherAPI public static final Runtime RUNTIME = Runtime.getRuntime();
-    @LauncherAPI public static final URLClassLoader LOADER = (URLClassLoader) ClassLoader.getSystemClassLoader();
-    @LauncherAPI public static final URLClassPath UCP = getURLClassPath();
+    @LauncherAPI public static final ClassLoader LOADER = ClassLoader.getSystemClassLoader();
 
     // Useful internal fields and constants
     private static final String JAVA_LIBRARY_PATH = "java.library.path";
-    private static final Field USR_PATHS_FIELD = getUsrPathsField();
-    private static final Field SYS_PATHS_FIELD = getSysPathsField();
+    private static final Field USR_PATHS_FIELD;
+    private static final Field SYS_PATHS_FIELD;
+    private static final Object UCP;
+    private static final Method UCP_ADDURL_METHOD;
+    private static final Method UCP_GETURLS_METHOD;
+    private static final Method UCP_GETRESOURCE_METHOD;
+    private static final Method RESOURCE_GETCERTS_METHOD;
 
     private JVMHelper() {
     }
 
     @LauncherAPI
+    public static void addClassPath(URL url) {
+        try {
+            UCP_ADDURL_METHOD.invoke(UCP, url);
+        } catch (IllegalAccessException | InvocationTargetException e) {
+            throw new InternalError(e);
+        }
+    }
+
+    @LauncherAPI
     public static void addNativePath(Path path) {
         String stringPath = path.toString();
 
@@ -71,6 +84,25 @@
     }
 
     @LauncherAPI
+    public static Certificate[] getCertificates(String resource) {
+        try {
+            Object resource0 = UCP_GETRESOURCE_METHOD.invoke(UCP, resource);
+            return resource0 == null ? null : (Certificate[]) RESOURCE_GETCERTS_METHOD.invoke(resource0);
+        } catch (IllegalAccessException | InvocationTargetException e) {
+            throw new InternalError(e);
+        }
+    }
+
+    @LauncherAPI
+    public static URL[] getClassPath() {
+        try {
+            return (URL[]) UCP_GETURLS_METHOD.invoke(UCP);
+        } catch (IllegalAccessException | InvocationTargetException e) {
+            throw new InternalError(e);
+        }
+    }
+
+    @LauncherAPI
     public static void halt0(int status) {
         LogHelper.debug("Trying to halt JVM");
         try {
@@ -131,26 +163,16 @@
         return Math.min(physicalRam, OS_BITS == 32 ? 1536 : 4096); // Limit 32-bit OS to 1536 MiB, and 64-bit OS to 4096 MiB (because it's enough)
     }
 
-    private static Field getSysPathsField() {
+    static {
         try {
-            return getField(ClassLoader.class, "sys_paths");
-        } catch (NoSuchFieldException e) {
-            throw new InternalError(e);
-        }
-    }
-
-    private static URLClassPath getURLClassPath() {
-        try {
-            return (URLClassPath) getField(URLClassLoader.class, "ucp").get(LOADER);
-        } catch (NoSuchFieldException | IllegalAccessException e) {
-            throw new InternalError(e);
-        }
-    }
-
-    private static Field getUsrPathsField() {
-        try {
-            return getField(ClassLoader.class, "usr_paths");
-        } catch (NoSuchFieldException e) {
+            USR_PATHS_FIELD = getField(ClassLoader.class, "usr_paths");
+            SYS_PATHS_FIELD = getField(ClassLoader.class, "sys_paths");
+            UCP = getField(LOADER.getClass(), "ucp").get(LOADER);
+            UCP_ADDURL_METHOD = getMethod(UCP.getClass(), "addURL", URL.class);
+            UCP_GETURLS_METHOD = getMethod(UCP.getClass(), "getURLs");
+            UCP_GETRESOURCE_METHOD = getMethod(UCP.getClass(), "getResource", String.class);
+            RESOURCE_GETCERTS_METHOD = getMethod(UCP_GETRESOURCE_METHOD.getReturnType(), "getCertificates");
+        } catch (NoSuchFieldException | NoSuchMethodException | IllegalAccessException e) {
             throw new InternalError(e);
         }
     }
diff --git a/Launcher/source/helper/SecurityHelper.java b/Launcher/source/helper/SecurityHelper.java
index ca66736..c5f5bd8 100644
--- a/Launcher/source/helper/SecurityHelper.java
+++ b/Launcher/source/helper/SecurityHelper.java
@@ -31,7 +31,6 @@
 import javax.crypto.NoSuchPaddingException;
 
 import launcher.LauncherAPI;
-import sun.misc.Resource;
 
 public final class SecurityHelper {
     // Algorithm constants
@@ -124,8 +123,8 @@
     @LauncherAPI
     public static boolean isValidCertificates(Class<?> clazz) {
         // Verify META-INF/MANIFEST.MF certificate
-        Resource metaInf = JVMHelper.UCP.getResource(JarFile.MANIFEST_NAME);
-        if (metaInf == null || !isValidCertificates(metaInf.getCertificates())) {
+        Certificate[] certificates = JVMHelper.getCertificates(JarFile.MANIFEST_NAME);
+        if (certificates == null || !isValidCertificates(certificates)) {
             return false;
         }