From 0ab02d696593b1507e0fcfdbfd2af50e1ed5e74b Mon Sep 17 00:00:00 2001
From: Mark Struberg <struberg@apache.org>
Date: Fri, 14 Jul 2023 12:15:54 +0200
Subject: [PATCH] OPENJPA-2911 AuxilaryEnhancer in ASM

---
 .../apache/openjpa/enhance/PCEnhancer.java    | 10 ++---
 .../stats/FetchStatisticsAuxEnhancer.java     | 39 ++++++++++---------
 2 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/openjpa-kernel/src/main/java/org/apache/openjpa/enhance/PCEnhancer.java b/openjpa-kernel/src/main/java/org/apache/openjpa/enhance/PCEnhancer.java
index a3593904e..7ea61e1c0 100644
--- a/openjpa-kernel/src/main/java/org/apache/openjpa/enhance/PCEnhancer.java
+++ b/openjpa-kernel/src/main/java/org/apache/openjpa/enhance/PCEnhancer.java
@@ -605,10 +605,9 @@ public class PCEnhancer {
                 addAttachDetachCode();
                 addSerializationCode();
                 addCloningCode();
+                runAuxiliaryEnhancers();
 
                 AsmHelper.readIntoBCClass(pc, _pc);
-
-                runAuxiliaryEnhancers();
                 return ENHANCE_PC;
             }
             return ENHANCE_AWARE;
@@ -4209,7 +4208,7 @@ public class PCEnhancer {
      */
     private void runAuxiliaryEnhancers() {
         for (AuxiliaryEnhancer auxEnhancer : _auxEnhancers) {
-            auxEnhancer.run(_pc, _meta);
+            auxEnhancer.run(pc.getClassNode(), _meta);
         }
     }
 
@@ -5747,10 +5746,7 @@ public class PCEnhancer {
      */
     public interface AuxiliaryEnhancer
     {
-        void run (BCClass bc, ClassMetaData meta);
-
-        @Deprecated
-        boolean skipEnhance(BCMethod m);
+        void run (ClassNode classNode, ClassMetaData meta);
 
         boolean skipEnhance(MethodNode m);
     }
diff --git a/openjpa-tools/openjpa-fetch-statistics/src/main/java/org/apache/openjpa/enhance/stats/FetchStatisticsAuxEnhancer.java b/openjpa-tools/openjpa-fetch-statistics/src/main/java/org/apache/openjpa/enhance/stats/FetchStatisticsAuxEnhancer.java
index 07989ea61..3c4ad9a5b 100644
--- a/openjpa-tools/openjpa-fetch-statistics/src/main/java/org/apache/openjpa/enhance/stats/FetchStatisticsAuxEnhancer.java
+++ b/openjpa-tools/openjpa-fetch-statistics/src/main/java/org/apache/openjpa/enhance/stats/FetchStatisticsAuxEnhancer.java
@@ -28,10 +28,13 @@ import org.apache.openjpa.meta.AccessCode;
 import org.apache.openjpa.meta.ClassMetaData;
 import org.apache.openjpa.meta.FieldMetaData;
 
+import org.apache.openjpa.util.asm.AsmHelper;
+import org.apache.xbean.asm9.Opcodes;
+import org.apache.xbean.asm9.Type;
+import org.apache.xbean.asm9.tree.ClassNode;
+import org.apache.xbean.asm9.tree.InsnList;
+import org.apache.xbean.asm9.tree.MethodInsnNode;
 import org.apache.xbean.asm9.tree.MethodNode;
-import serp.bytecode.BCClass;
-import serp.bytecode.BCMethod;
-import serp.bytecode.Code;
 
 /**
  * FetchStatisticsAuxEnhancer adds the call back function to each persistent fields in the persistent entity which
@@ -43,13 +46,8 @@ public class FetchStatisticsAuxEnhancer implements AuxiliaryEnhancer {
         + "(pc(.)*DetachedState)?(pc(.)*EnhancementContractVersion)?(pc(.)*ManagedFieldCount)?(pc(.)*GetVersion)?";
 
     @Override
-    public void run(BCClass bcc, ClassMetaData cmd) {
-        addEnhancement(bcc, cmd);
-    }
-
-    @Override
-    public boolean skipEnhance(BCMethod arg0) {
-        return false;
+    public void run(ClassNode classNode, ClassMetaData cmd) {
+        addEnhancement(classNode, cmd);
     }
 
     @Override
@@ -57,21 +55,26 @@ public class FetchStatisticsAuxEnhancer implements AuxiliaryEnhancer {
         return false;
     }
 
-    private void addEnhancement(BCClass bcc, ClassMetaData cmd) {
+    private void addEnhancement(ClassNode classNode, ClassMetaData cmd) {
         Log log = cmd.getRepository().getConfiguration().getLog(OpenJPAConfiguration.LOG_RUNTIME);
         FetchStatsCollector.setlogger(log);
-        for (BCMethod meth : bcc.getMethods()) {
-            String methodName = meth.getName();
+        String className = classNode.name.replace("/", ".");
+        for (MethodNode meth : classNode.methods) {
+            String methodName = meth.name;
             FieldMetaData fmd = getFieldName(methodName, cmd);
             if (fmd != null && needsTracking(fmd, methodName, cmd)) {
-                String fqn = bcc.getName() + "." + fmd.getName();
+                String fqn = className + "." + fmd.getName();
                 FetchStatsCollector.registerField(fqn);
                 FetchStatsCollector.registerEntity(cmd);
 
-                Code code = meth.getCode(false);
-                code.constant().setValue(fqn);
-                code.invokestatic().setMethod(FetchStatsCollector.class, "hit", void.class,
-                    new Class[] { String.class });
+                InsnList instructions = new InsnList();
+
+                instructions.add(AsmHelper.getLoadConstantInsn(fqn));
+                instructions.add(new MethodInsnNode(Opcodes.INVOKESTATIC,
+                                                    Type.getInternalName(FetchStatsCollector.class),
+                                                    "hit",
+                                                    Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(String.class))));
+                meth.instructions.insert(instructions);
             }
         }
     }