[incubator-kie-issues#1497] Defining NodeInstanceContainer.getSeriali…

…zableNodeInstances to be used during serialization (apache#6116)

Co-authored-by: Gabriele-Cardosi <[email protected]>

kie-api/src/main/java/org/kie/api/runtime/process/NodeInstanceContainer.java

@@ -34,6 +34,16 @@ public interface NodeInstanceContainer {
      */
     Collection<NodeInstance> getNodeInstances();
 
+    /**
+     * Returns all node instances that are currently active
+     * within this container and are serializable
+     *
+     * @return the list of serializable node instances currently active
+     */
+    default Collection<NodeInstance> getSerializableNodeInstances() {
+        return getNodeInstances(); // defaulting to getNodeInstances to avoid breaking
+    }
+
     /**
      * Returns the node instance with the given id, or <code>null</code>
      * if the node instance cannot be found.