parallel compilation wip - use lock

Author: fglock

src/main/java/org/perlonjava/codegen/EmitterMethodCreator.java

@@ -10,6 +10,7 @@
 import java.io.StringWriter;
 import java.lang.annotation.Annotation;
 import java.lang.reflect.*;
+import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * EmitterMethodCreator is a utility class that uses the ASM library to dynamically generate Java
@@ -77,6 +78,8 @@ public static String getVariableClassName(String varName) {
         };
     }
 
+    private static final ReentrantLock lock = new ReentrantLock();
+
     /**
      * Creates a new class with a method based on the provided context, environment, and abstract
      * syntax tree (AST).
@@ -87,10 +90,15 @@ public static String getVariableClassName(String varName) {
      * @return The generated class.
      */
     public static Class<?> createClassWithMethod(EmitterContext ctx, Node ast, boolean useTryCatch) {
-
-        byte[] classData = getBytecode(ctx, ast, useTryCatch);
-
-        return loadBytecode(ctx, classData);
+        lock.lock();
+        Class<?> aClass;
+        try {
+            byte[] classData = getBytecode(ctx, ast, useTryCatch);
+            aClass = loadBytecode(ctx, classData);
+        } finally {
+            lock.unlock();
+        }
+        return aClass;
     }
 
     public static byte[] getBytecode(EmitterContext ctx, Node ast, boolean useTryCatch) {

src/main/java/org/perlonjava/parser/SubroutineParser.java

@@ -259,32 +259,13 @@ private static ListNode handleNamedSub(Parser parser, String subName, String pro
                 new RuntimeArray()
         );
 
-        // Generate bytecode for the subroutine block
-        byte[] classData = EmitterMethodCreator.getBytecode(newCtx, block, false);
-        // System.out.println("Creating subroutine " + fullName);
-        // Load the generated bytecode into a Class object
-        Class<?> generatedClass = EmitterMethodCreator.loadBytecode(newCtx, classData);
-
         // Create a Runnable to execute the subroutine creation
         Runnable subroutineCreationTask = () -> {
-
-            // The following commented-out code is a work in progress for handling concurrency
-//                Class<?> generatedClass = null;
-//                try {
-//                    semaphore.acquire();
-//                    byte[] classData = EmitterMethodCreator.getBytecode(newCtx, block, false);
-//                    // System.out.println("Creating subroutine " + fullName);
-//                    generatedClass = EmitterMethodCreator.loadBytecode(newCtx, classData);
-//
-//                } catch (InterruptedException e) {
-//                    throw new RuntimeException(e);
-//                } finally {
-//                    // Release the semaphore
-//                    semaphore.release();
-//                }
-
+            // Generate bytecode and load into a Class object
+            Class<?> generatedClass = EmitterMethodCreator.createClassWithMethod(newCtx, block, false);
             // System.out.println("Class " + generatedClass);
             // EmitterMethodCreator.debugInspectClass(generatedClass);
+
             try {
                 // Prepare constructor with the captured variable types
                 Class<?>[] parameterTypes = classList.toArray(new Class<?>[0]);