fix json path node class cast exception

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/transform/TbJsonPathNode.java

@@ -70,7 +70,7 @@ public class TbJsonPathNode implements TbNode {
     public void onMsg(TbContext ctx, TbMsg msg) throws ExecutionException, InterruptedException, TbNodeException {
         if (!TbJsonPathNodeConfiguration.DEFAULT_JSON_PATH.equals(this.jsonPathValue)) {
             try {
-                JsonNode jsonPathData = jsonPath.read(msg.getData(), this.configurationJsonPath);
+                Object jsonPathData = jsonPath.read(msg.getData(), this.configurationJsonPath);
                 ctx.tellSuccess(TbMsg.transformMsg(msg, msg.getType(), msg.getOriginator(), msg.getMetaData(), JacksonUtil.toString(jsonPathData)));
             } catch (PathNotFoundException e) {
                 ctx.tellFailure(msg, e);

rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/transform/TbJsonPathNodeTest.java

@@ -85,7 +85,7 @@ public class TbJsonPathNodeTest {
     }
 
     @Test
-    void givenPrimitiveMsg_whenOnMsg_thenVerifyOutput() throws Exception {
+    void givenJsonMsg_whenOnMsg_thenVerifyOutputJsonPrimitiveNode() throws Exception {
         String data = "{\"Attribute_1\":22.5,\"Attribute_2\":100}";
         VerifyOutputMsg(data, 1, 100);
 
@@ -93,6 +93,17 @@ public class TbJsonPathNodeTest {
         VerifyOutputMsg(data, 2, "StringValue");
     }
 
+    @Test
+    void givenJsonMsg_whenOnMsg_thenVerifyJavaPrimitiveOutput() throws Exception {
+        config.setJsonPath("$.attributes.length()");
+        nodeConfiguration = new TbNodeConfiguration(mapper.valueToTree(config));
+        node.init(ctx, nodeConfiguration);
+
+        String data = "{\"attributes\":[{\"attribute_1\":10},{\"attribute_2\":20},{\"attribute_3\":30},{\"attribute_4\":40}]}";
+        VerifyOutputMsg(data, 1, 4);
+
+    }
+
     @Test
     void givenJsonArray_whenOnMsg_thenVerifyOutput() throws Exception {
         String data = "{\"Attribute_1\":22.5,\"Attribute_2\":[{\"Attribute_3\":22.5,\"Attribute_4\":10.3}, {\"Attribute_5\":22.5,\"Attribute_6\":10.3}]}";