change: Simplify class define tool to call java 16's api explicitly (#42

) Co-authored-by: liach <[email protected]>
CaffeineMC · Jul 15, 2021 · e64d970 · e64d970
1 parent db37ae1
commit e64d970
Showing 1 changed file with 5 additions and 26 deletions.
diff --git a/src/main/java/me/jellysquid/mods/hydrogen/common/jvm/ClassDefineTool.java b/src/main/java/me/jellysquid/mods/hydrogen/common/jvm/ClassDefineTool.java
@@ -1,40 +1,18 @@
 package me.jellysquid.mods.hydrogen.common.jvm;
 
-import jdk.dynalink.linker.support.Lookup;
 import org.apache.commons.io.IOUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
 import java.io.IOException;
-import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
-import java.lang.invoke.MethodType;
 import java.net.URL;
 
 public class ClassDefineTool {
-    private static final MethodHandles.Lookup LOOKUP;
-
-    private static final MethodHandle DEFINE_CLASS_METHOD;
-    private static final MethodHandle PRIVATE_LOOKUP_IN_METHOD;
+    private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup();
 
     private static final Logger LOGGER = LogManager.getLogger("Hydrogen");
 
-    static {
-        LOOKUP = MethodHandles.lookup();
-
-        try {
-            PRIVATE_LOOKUP_IN_METHOD = LOOKUP.findStatic(MethodHandles.class, "privateLookupIn",
-                    MethodType.methodType(MethodHandles.Lookup.class, Class.class, MethodHandles.Lookup.class));
-
-            DEFINE_CLASS_METHOD = LOOKUP.findVirtual(MethodHandles.Lookup.class, "defineClass",
-                    MethodType.methodType(Class.class, byte[].class));
-        } catch (IllegalAccessException e) {
-            throw new RuntimeException("Couldn't access method", e);
-        } catch (NoSuchMethodException e) {
-            throw new RuntimeException("Couldn't locate method", e);
-        }
-    }
-
     public static Class<?> defineClass(Class<?> context, String name) {
         String path = "/" + name.replace('.', '/') + ".class";
         URL url = ClassDefineTool.class.getResource(path);
@@ -54,9 +32,10 @@ public static Class<?> defineClass(Class<?> context, String name) {
         }
 
         try {
-            MethodHandles.Lookup privateLookup = (MethodHandles.Lookup) PRIVATE_LOOKUP_IN_METHOD.invokeExact((Class<?>) context, (MethodHandles.Lookup) LOOKUP);
-
-            return (Class<?>) DEFINE_CLASS_METHOD.invokeExact(privateLookup, (byte[]) code);
+            // The context class need to be in a module that exports and opens to ClassDefineTool
+            // Example: guava's automatic module exports and opens to everything
+            MethodHandles.Lookup privateLookup = MethodHandles.privateLookupIn(context, LOOKUP);
+            return privateLookup.defineClass(code);
         } catch (Throwable throwable) {
             throw new RuntimeException("Failed to define class", throwable);
         }