Use one lock per serialization / deserialization beans to prevent deadlock

serde-support/src/main/java/io/micronaut/serde/support/deserializers/DeserBean.java

@@ -61,6 +61,7 @@
 import java.util.OptionalInt;
 import java.util.OptionalLong;
 import java.util.Set;
+import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.BiConsumer;
 import java.util.function.Predicate;
 
@@ -426,16 +427,19 @@ public AnnotationMetadata getAnnotationMetadata() {
         recordLikeBean = isRecordLikeBean();
     }
 
-    void initialize(Deserializer.DecoderContext decoderContext) throws SerdeException {
+    void initialize(ReentrantLock lock, Deserializer.DecoderContext decoderContext) throws SerdeException {
         // Double check locking
         if (!initialized) {
-            synchronized (this) {
+            lock.lock();
+            try {
                 if (!initialized && !initializing) {
                     initializing = true;
                     initializeInternal(decoderContext);
                     initialized = true;
                     initializing = false;
                 }
+            } finally {
+                lock.unlock();
             }
         }
     }

serde-support/src/main/java/io/micronaut/serde/support/deserializers/ObjectDeserializer.java

@@ -34,6 +34,7 @@
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Supplier;
 
 /**
@@ -51,6 +52,8 @@ public class ObjectDeserializer implements CustomizableDeserializer<Object>, Des
     @Nullable
     private final SerdeDeserializationPreInstantiateCallback preInstantiateCallback;
 
+    private final ReentrantLock lock = new ReentrantLock();
+
     public ObjectDeserializer(SerdeIntrospections introspections,
                               DeserializationConfiguration deserializationConfiguration,
                               SerdeConfiguration serdeConfiguration,
@@ -155,7 +158,7 @@ public <T> DeserBean<T> getDeserializableBean(Argument<T> type, DecoderContext d
         // Use suppliers to prevent recursive update because the lambda can call the same method again
         Supplier<DeserBean<?>> deserBeanSupplier = deserBeanMap.computeIfAbsent(key, ignore -> SupplierUtil.memoizedNonEmpty(() -> createDeserBean(type, serdeArgumentConf, decoderContext)));
         DeserBean<?> deserBean = deserBeanSupplier.get();
-        deserBean.initialize(decoderContext);
+        deserBean.initialize(lock, decoderContext);
         return (DeserBean<T>) deserBean;
     }
 

serde-support/src/main/java/io/micronaut/serde/support/serializers/ObjectSerializer.java

@@ -36,6 +36,7 @@
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Supplier;
 
 /**
@@ -59,6 +60,8 @@ public final class ObjectSerializer implements CustomizableSerializer<Object> {
     @Nullable
     private final BeanContext beanContext;
 
+    private final ReentrantLock lock = new ReentrantLock();
+
     public ObjectSerializer(SerdeIntrospections introspections,
                             SerdeConfiguration serdeConfiguration,
                             SerializationConfiguration serializationConfiguration) {
@@ -162,7 +165,7 @@ private <T> SerBean<T> getSerializableBean(Argument<T> type,
             }
         }));
         SerBean<?> serBean = serBeanSupplier.get();
-        serBean.initialize(context);
+        serBean.initialize(lock, context);
         return (SerBean<T>) serBean;
     }
 }

serde-support/src/main/java/io/micronaut/serde/support/serializers/SerBean.java

@@ -58,6 +58,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Function;
 import java.util.function.Predicate;
 
@@ -377,9 +378,11 @@ private static PropertySubtypeDescriptor findDescriptor(@Nullable SubtypeInfo su
         }
     }
 
-    public void initialize(Serializer.EncoderContext encoderContext) throws SerdeException {
+    public void initialize(ReentrantLock lock, Serializer.EncoderContext encoderContext) throws SerdeException {
+        // Double check locking
         if (!initialized) {
-            synchronized (this) {
+            lock.lock();
+            try {
                 if (!initialized && !initializing) {
                     initializing = true;
                     for (Initializer initializer : initializers) {
@@ -389,6 +392,8 @@ public void initialize(Serializer.EncoderContext encoderContext) throws SerdeExc
                     initialized = true;
                     initializing = false;
                 }
+            } finally {
+                lock.unlock();
             }
         }
     }