Don't use ThreadLocals for @JsonAdapter factories and getDelegateAdapter().

gson/src/main/java/com/google/gson/Gson.java

@@ -488,26 +488,28 @@ public final class Gson {
    * @since 2.2
    */
   public <T> TypeAdapter<T> getDelegateAdapter(TypeAdapterFactory skipPast, TypeToken<T> type) {
-    // If the specified skipPast factory is not registered, ignore it.
+    boolean skipPastFound = false;
-    boolean skipPastFound = skipPast == null
+
-        || (!factories.contains(skipPast) && jsonAdapterFactory.getDelegateAdapterFactory(type) == null);
+    // Hack. If the skipPast factory isn't registered, assume the factory is being requested via
+    // our @JsonAdapter annotation.
+    if (!factories.contains(skipPast)) {
+      skipPast = jsonAdapterFactory;
+    }
 
     for (TypeAdapterFactory factory : factories) {
       if (!skipPastFound) {
-        skipPastFound = factory == skipPast;
+        if (factory == skipPast) {
-        if (!skipPastFound && factory instanceof JsonAdapterAnnotationTypeAdapterFactory) {
+          skipPastFound = true;
-          // Also check if there is a registered JsonAdapter for it
-          factory = ((JsonAdapterAnnotationTypeAdapterFactory)factory).getDelegateAdapterFactory(type);
-          skipPastFound = factory == skipPast;
         }
         continue;
       }
+
       TypeAdapter<T> candidate = factory.create(this, type);
       if (candidate != null) {
         return candidate;
       }
     }
-    throw new IllegalArgumentException("GSON cannot serialize or deserialize " + type);
+    throw new IllegalArgumentException("GSON cannot serialize " + type);
   }
 
   /**

gson/src/main/java/com/google/gson/internal/bind/JsonAdapterAnnotationTypeAdapterFactory.java

@@ -16,9 +16,6 @@
 
 package com.google.gson.internal.bind;
 
-import java.util.HashMap;
-import java.util.Map;
-
 import com.google.gson.Gson;
 import com.google.gson.JsonDeserializer;
 import com.google.gson.JsonSerializer;
@@ -35,15 +32,6 @@ import com.google.gson.reflect.TypeToken;
  * @since 2.3
  */
 public final class JsonAdapterAnnotationTypeAdapterFactory implements TypeAdapterFactory {
-
-  @SuppressWarnings("rawtypes")
-  private final ThreadLocal<Map<Class, TypeAdapterFactory>> activeJsonAdapterFactories = new ThreadLocal<Map<Class, TypeAdapterFactory>>() {
-    @Override protected Map<Class, TypeAdapterFactory> initialValue() {
-      // No need for a thread-safe map since we are using it in a single thread
-      return new HashMap<Class, TypeAdapterFactory>();
-    }
-  };
-
   private final ConstructorConstructor constructorConstructor;
 
   public JsonAdapterAnnotationTypeAdapterFactory(ConstructorConstructor constructorConstructor) {
@@ -61,75 +49,34 @@ public final class JsonAdapterAnnotationTypeAdapterFactory implements TypeAdapte
     return (TypeAdapter<T>) getTypeAdapter(constructorConstructor, gson, targetType, annotation);
   }
 
-  public <T> TypeAdapter<T> getDelegateAdapter(Gson gson, TypeAdapterFactory skipPast, TypeToken<T> targetType) {
-    TypeAdapterFactory factory = getDelegateAdapterFactory(targetType);
-    if (factory == skipPast) factory = null;
-    return factory == null ? null: factory.create(gson, targetType);
-  }
-
-  public <T> TypeAdapterFactory getDelegateAdapterFactory(TypeToken<T> targetType) {
-    Class<?> annotatedClass = targetType.getRawType();
-    JsonAdapter annotation = annotatedClass.getAnnotation(JsonAdapter.class);
-    if (annotation == null) {
-      return null;
-    }
-    return getTypeAdapterFactory(annotation, constructorConstructor);
-  }
-
   @SuppressWarnings({ "unchecked", "rawtypes" }) // Casts guarded by conditionals.
   TypeAdapter<?> getTypeAdapter(ConstructorConstructor constructorConstructor, Gson gson,
       TypeToken<?> type, JsonAdapter annotation) {
-    Class<?> value = annotation.value();
+    Object instance = constructorConstructor.get(TypeToken.get(annotation.value())).construct();
-    boolean isTypeAdapter = TypeAdapter.class.isAssignableFrom(value);
-    boolean isJsonSerializer = JsonSerializer.class.isAssignableFrom(value);
-    boolean isJsonDeserializer = JsonDeserializer.class.isAssignableFrom(value);
 
     TypeAdapter<?> typeAdapter;
-    if (isTypeAdapter || isJsonSerializer || isJsonDeserializer) {
+    if (instance instanceof TypeAdapter) {
-      if (isTypeAdapter) {
+      typeAdapter = (TypeAdapter<?>) instance;
-        Class<TypeAdapter<?>> typeAdapterClass = (Class<TypeAdapter<?>>) value;
+    } else if (instance instanceof TypeAdapterFactory) {
-        typeAdapter = constructorConstructor.get(TypeToken.get(typeAdapterClass)).construct();
+      typeAdapter = ((TypeAdapterFactory) instance).create(gson, type);
-      } else if (isJsonSerializer || isJsonDeserializer) {
+    } else if (instance instanceof JsonSerializer || instance instanceof JsonDeserializer) {
-        JsonSerializer serializer = null;
+      JsonSerializer<?> serializer = instance instanceof JsonSerializer
-        if (isJsonSerializer) {
+          ? (JsonSerializer) instance
-          Class<JsonSerializer<?>> serializerClass = (Class<JsonSerializer<?>>) value;
+          : null;
-          serializer = constructorConstructor.get(TypeToken.get(serializerClass)).construct();
+      JsonDeserializer<?> deserializer = instance instanceof JsonDeserializer
-        }
+          ? (JsonDeserializer) instance
-        JsonDeserializer deserializer = null;
+          : null;
-        if (isJsonDeserializer) {
+      typeAdapter = new TreeTypeAdapter(serializer, deserializer, gson, type, null);
-          Class<JsonDeserializer<?>> deserializerClass = (Class<JsonDeserializer<?>>) value;
-          deserializer = constructorConstructor.get(TypeToken.get(deserializerClass)).construct();
-        }
-        typeAdapter = new TreeTypeAdapter(serializer, deserializer, gson, type, null);
-      } else {
-        typeAdapter = null;
-      }
-    } else if (TypeAdapterFactory.class.isAssignableFrom(value)) {
-      TypeAdapterFactory factory = getTypeAdapterFactory(annotation, constructorConstructor);
-      typeAdapter = factory == null ? null : factory.create(gson, type);
     } else {
       throw new IllegalArgumentException(
-          "@JsonAdapter value must be TypeAdapter, TypeAdapterFactory, JsonSerializer or JsonDeserializer reference.");
+          "@JsonAdapter value must be TypeAdapter, TypeAdapterFactory, "
+              + "JsonSerializer or JsonDeserializer reference.");
     }
+
     if (typeAdapter != null) {
       typeAdapter = typeAdapter.nullSafe();
     }
+
     return typeAdapter;
   }
-
-
-  @SuppressWarnings({ "unchecked", "rawtypes" }) // Casts guarded by conditionals.
-  TypeAdapterFactory getTypeAdapterFactory(JsonAdapter annotation, ConstructorConstructor constructorConstructor) {
-    Class<?> value = annotation.value();
-    if (!TypeAdapterFactory.class.isAssignableFrom(value)) return null;
-    Map<Class, TypeAdapterFactory> adapterFactories = activeJsonAdapterFactories.get();
-    TypeAdapterFactory factory = adapterFactories.get(value);
-    if (factory == null) {
-      Class<TypeAdapterFactory> typeAdapterFactoryClass = (Class<TypeAdapterFactory>) value;
-      factory = constructorConstructor.get(TypeToken.get(typeAdapterFactoryClass))
-          .construct();
-      adapterFactories.put(value, factory);
-    }
-    return factory;
-  }
 }

gson/src/main/java/com/google/gson/internal/bind/ReflectiveTypeAdapterFactory.java

@@ -32,7 +32,6 @@ import com.google.gson.reflect.TypeToken;
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonToken;
 import com.google.gson.stream.JsonWriter;
-
 import java.io.IOException;
 import java.lang.reflect.Field;
 import java.lang.reflect.Type;
@@ -110,7 +109,7 @@ public final class ReflectiveTypeAdapterFactory implements TypeAdapterFactory {
     TypeAdapter<?> mapped = null;
     if (annotation != null) {
       mapped = jsonAdapterFactory.getTypeAdapter(
-                constructorConstructor, context, fieldType, annotation);
+          constructorConstructor, context, fieldType, annotation);
     }
     final boolean jsonAdapterPresent = mapped != null;
     if (mapped == null) mapped = context.getAdapter(fieldType);

gson/src/test/java/com/google/gson/functional/JsonAdapterSerializerDeserializerTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 Google Inc.
+ * Copyright (C) 2016 Google Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.