bug fix toJavaObject, for issue #2516

src/main/java/com/alibaba/fastjson/JSON.java

@@ -1107,6 +1107,10 @@ public static <T> T toJavaObject(JSON json, Class<T> clazz) {
      * @since 1.2.9
      */
     public <T> T toJavaObject(Class<T> clazz) {
+        if (clazz == JSONArray.class || clazz == JSON.class || clazz == Collection.class || clazz == List.class) {
+            return (T) this;
+        }
+
         return TypeUtils.cast(this, clazz, ParserConfig.getGlobalInstance());
     }
 

src/main/java/com/alibaba/fastjson/JSONObject.java

@@ -588,7 +588,7 @@ protected void readStreamHeader() throws IOException, StreamCorruptedException {
     }
 
     public <T> T toJavaObject(Class<T> clazz) {
-        if (clazz == Map.class) {
+        if (clazz == Map.class || clazz == JSONObject.class || clazz == JSON.class) {
             return (T) this;
         }
 

src/test/java/com/alibaba/json/bvt/issue_2500/Issue2516.java

@@ -0,0 +1,23 @@
+package com.alibaba.json.bvt.issue_2500;
+
+import com.alibaba.fastjson.JSON;
+import com.alibaba.fastjson.JSONArray;
+import com.alibaba.fastjson.JSONObject;
+import junit.framework.TestCase;
+
+import java.util.Collection;
+import java.util.List;
+
+public class Issue2516 extends TestCase
+{
+    public void test_for_issue() throws Exception {
+        JSONObject jsonObject = new JSONObject();
+        jsonObject.toJavaObject(JSONObject.class);
+        jsonObject.toJavaObject(JSON.class);
+
+        new JSONArray().toJavaObject(JSON.class);
+        new JSONArray().toJavaObject(JSONArray.class);
+        new JSONArray().toJavaObject(Collection.class);
+        new JSONArray().toJavaObject(List.class);
+    }
+}