diff --git a/src/main/java/com/alibaba/fastjson/JSONArray.java b/src/main/java/com/alibaba/fastjson/JSONArray.java
index f7485453f8..cdb1440597 100644
--- a/src/main/java/com/alibaba/fastjson/JSONArray.java
+++ b/src/main/java/com/alibaba/fastjson/JSONArray.java
@@ -131,20 +131,20 @@ public boolean containsAll(Collection<?> c) {
         return list.containsAll(c);
     }
 
-    public boolean addAll(Collection<? extends Object> c) {
+    public boolean addAll(Collection<?> c) {
         return list.addAll(c);
     }
 
-    public JSONArray fluentAddAll(Collection<? extends Object> c) {
+    public JSONArray fluentAddAll(Collection<?> c) {
         list.addAll(c);
         return this;
     }
 
-    public boolean addAll(int index, Collection<? extends Object> c) {
+    public boolean addAll(int index, Collection<?> c) {
         return list.addAll(index, c);
     }
 
-    public JSONArray fluentAddAll(int index, Collection<? extends Object> c) {
+    public JSONArray fluentAddAll(int index, Collection<?> c) {
         list.addAll(index, c);
         return this;
     }
diff --git a/src/main/java/com/alibaba/fastjson/JSONObject.java b/src/main/java/com/alibaba/fastjson/JSONObject.java
index 6b1031fc7a..9c2a9ac56c 100644
--- a/src/main/java/com/alibaba/fastjson/JSONObject.java
+++ b/src/main/java/com/alibaba/fastjson/JSONObject.java
@@ -352,11 +352,11 @@ public JSONObject fluentPut(String key, Object value) {
         return this;
     }
 
-    public void putAll(Map<? extends String, ? extends Object> m) {
+    public void putAll(Map<? extends String, ?> m) {
         map.putAll(m);
     }
 
-    public JSONObject fluentPutAll(Map<? extends String, ? extends Object> m) {
+    public JSONObject fluentPutAll(Map<? extends String, ?> m) {
         map.putAll(m);
         return this;
     }
diff --git a/src/main/java/com/alibaba/fastjson/support/spring/FastJsonHttpMessageConverter.java b/src/main/java/com/alibaba/fastjson/support/spring/FastJsonHttpMessageConverter.java
index a3fbd43443..0f8a16240f 100644
--- a/src/main/java/com/alibaba/fastjson/support/spring/FastJsonHttpMessageConverter.java
+++ b/src/main/java/com/alibaba/fastjson/support/spring/FastJsonHttpMessageConverter.java
@@ -250,7 +250,7 @@ public void write(Object o, Type type, MediaType contentType, HttpOutputMessage
      * @see org.springframework.http.converter.AbstractHttpMessageConverter#readInternal(java.lang.Class, org.springframework.http.HttpInputMessage)
      */
     @Override
-    protected Object readInternal(Class<? extends Object> clazz, //
+    protected Object readInternal(Class<?> clazz, //
                                   HttpInputMessage inputMessage //
     ) throws IOException, HttpMessageNotReadableException {
         return readType(getType(clazz, null), inputMessage);