Node Visitor Interface

The Node Visitor Interface is a software component that defines a standardized protocol for implementing the visitor design pattern within industrial tree traversal engines. It enables external algorithms to traverse hierarchical data structures (such as production workflows, equipment hierarchies, or quality control trees) without modifying the underlying node classes. This interface provides methods for visiting different node types, processing node data, and accumulating results during traversal operations in industrial automation environments.

The interface operates on the visitor design pattern principle, where a visitor object implements specific visit methods for different node types. When a tree traversal engine processes hierarchical data, it calls the appropriate visit method on the visitor interface for each node encountered. This separation allows traversal algorithms to be decoupled from node processing logic, enabling flexible extension of functionality without modifying existing node structures. The interface typically includes methods like visitRootNode(), visitBranchNode(), visitLeafNode(), and postVisit() for result aggregation.