fix: prevent StackOverflowError in ObjectView JSON mode for circular references

core/src/main/java/com/taobao/arthas/core/view/ObjectView.java

@@ -38,13 +38,20 @@ protected void setDefaultValue(List<FieldWriter> fieldWriters, Class objectClass
             });
 
     public static String toJsonString(Object object) {
-        JSONWriter.Context context = new JSONWriter.Context(JSON_OBJECT_WRITER_PROVIDER);
-        context.setMaxLevel(4097);
-        context.config(JSONWriter.Feature.IgnoreErrorGetter,
-                JSONWriter.Feature.ReferenceDetection,
-                JSONWriter.Feature.IgnoreNonFieldGetter,
-                JSONWriter.Feature.WriteNonStringKeyAsString);
-        return JSON.toJSONString(object, context);
+        try {
+            JSONWriter.Context context = new JSONWriter.Context(JSON_OBJECT_WRITER_PROVIDER);
+            context.setMaxLevel(4097);
+            context.config(JSONWriter.Feature.IgnoreErrorGetter,
+                    JSONWriter.Feature.ReferenceDetection,
+                    JSONWriter.Feature.IgnoreNonFieldGetter,
+                    JSONWriter.Feature.WriteNonStringKeyAsString);
+            return JSON.toJSONString(object, context);
+        } catch (StackOverflowError e) {
+            logger.error("ObjectView JSON serialization stackoverflow, object class: {}", object == null ? "null" : object.getClass(), e);
+            return "ERROR DATA!!! object class: " + (object == null ? "null" : object.getClass())
+                    + ", StackOverflowError: circular reference or object graph too deep. "
+                    + "Try disabling json mode: options json false";
+        }
     }
 
     private final Object object;

core/src/test/java/com/taobao/arthas/core/view/ObjectViewTest.java

@@ -393,4 +393,27 @@ public static JsonFormatSingleton getInstance() {
             return INSTANCE;
         }
     }
+
+    @Test
+    public void testJsonModeCircularReference() {
+        GlobalOptions.isUsingJson = true;
+        try {
+            CircularRef a = new CircularRef("a");
+            CircularRef b = new CircularRef("b");
+            a.ref = b;
+            b.ref = a;
+            ObjectView objectView = new ObjectView(a, 3);
+            String result = objectView.draw();
+            // Should not throw StackOverflowError
+            Assert.assertNotNull(result);
+        } finally {
+            GlobalOptions.isUsingJson = false;
+        }
+    }
+
+    private static class CircularRef {
+        String name;
+        CircularRef ref;
+        CircularRef(String name) { this.name = name; }
+    }
 }