Fix ClassCircularityError in the ASURLClassLoader

Signed-off-by: Alexander Pinčuk <alexander.v.pinchuk@gmail.com>
eclipse-ee4j · Jun 4, 2023 · 1127fe0 · 1127fe0
1 parent e6610fe
commit 1127fe0
Showing 1 changed file with 24 additions and 10 deletions.
diff --git a/nucleus/common/common-util/src/main/java/com/sun/enterprise/loader/ASURLClassLoader.java b/nucleus/common/common-util/src/main/java/com/sun/enterprise/loader/ASURLClassLoader.java
@@ -72,6 +72,7 @@
 import org.glassfish.common.util.GlassfishUrlClassLoader;
 import org.glassfish.hk2.api.PreDestroy;
 
+import static java.lang.ThreadLocal.withInitial;
 import static java.util.logging.Level.INFO;
 
 /**
@@ -118,6 +119,9 @@ public class ASURLClassLoader extends GlassfishUrlClassLoader
 
     private final ArrayList<ClassFileTransformer> transformers = new ArrayList<>(1);
 
+    /** Bytecode transformation flag */
+    private static final ThreadLocal<Boolean> BYTECODE_TRANSFORMATION = withInitial(() -> false);
+
     private final static StringManager sm = StringManager.getManager(ASURLClassLoader.class);
 
     //holder for declared and ee permissions
@@ -710,16 +714,26 @@ protected Class<?> findClass(String name) throws ClassNotFoundException {
         try {
             @SuppressWarnings("unchecked")
             final List<ClassFileTransformer> xformers = (ArrayList<ClassFileTransformer>) transformers.clone();
-            for (final ClassFileTransformer transformer : xformers) {
-                // see javadocs of transform().
-                // It expects class name as java/lang/Object
-                // as opposed to java.lang.Object
-                final String internalClassName = name.replace('.','/');
-                final byte[] transformedBytes = transformer.transform(this, internalClassName, null,
-                    classData.pd, classData.getClassBytes());
-                if (transformedBytes != null) { // null indicates no transformation
-                    _logger.log(INFO, CULoggerInfo.actuallyTransformed, name);
-                    classData.setClassBytes(transformedBytes);
+            if (!xformers.isEmpty()) {
+                // Do not transform classes loaded by a transformers itself
+                if (!BYTECODE_TRANSFORMATION.get()) {
+                    BYTECODE_TRANSFORMATION.set(true);
+                    try {
+                        for (final ClassFileTransformer transformer : xformers) {
+                            // see javadocs of transform().
+                            // It expects class name as java/lang/Object
+                            // as opposed to java.lang.Object
+                            final String internalClassName = name.replace('.', '/');
+                            final byte[] transformedBytes = transformer.transform(this, internalClassName, null,
+                                    classData.pd, classData.getClassBytes());
+                            if (transformedBytes != null) { // null indicates no transformation
+                                _logger.log(INFO, CULoggerInfo.actuallyTransformed, name);
+                                classData.setClassBytes(transformedBytes);
+                            }
+                        }
+                    } finally {
+                        BYTECODE_TRANSFORMATION.set(false);
+                    }
                 }
             }
         } catch (IllegalClassFormatException icfEx) {