Package com.cedarsoftware.util

Class Traverser

java.lang.Object
com.cedarsoftware.util.Traverser
public class Traverser extends Object
A Java Object Graph traverser that visits all object reference fields and invokes a provided callback for each encountered object, including the root. It properly detects cycles within the graph to prevent infinite loops. For each visited node, complete field information including metadata is provided.

Usage Examples:

Using the Modern API (Recommended):


 // Define classes to skip (optional)
 Set<Class<?>> classesToSkip = new HashSet<>();
 classesToSkip.add(String.class);

 // Traverse with full node information
 Traverser.traverse(root, classesToSkip, visit -> {
     System.out.println("Node: " + visit.getNode());
     visit.getFields().forEach((field, value) -> {
         System.out.println("  Field: " + field.getName() +
             " (type: " + field.getType().getSimpleName() + ") = " + value);

         // Access field metadata if needed
         if (field.isAnnotationPresent(JsonProperty.class)) {
             JsonProperty ann = field.getAnnotation(JsonProperty.class);
             System.out.println("    JSON property: " + ann.value());
         }
     });
 });

Using the Legacy API (Deprecated):


 // Define a visitor that processes each object
 Traverser.Visitor visitor = new Traverser.Visitor() {
     @Override
     public void process(Object o) {
         System.out.println("Visited: " + o);
     }
 };

 // Create an object graph and traverse it
 SomeClass root = new SomeClass();
 Traverser.traverse(root, visitor);

Thread Safety: This class is not thread-safe. If multiple threads access a Traverser instance concurrently, external synchronization is required.

Author:
John DeRegnaucourt ([email protected])
Copyright (c) Cedar Software LLC

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

License

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

  • Method Details

    • traverse

      public static void traverse(Object root, Consumer<Traverser.NodeVisit> visitor, Set<Class<?>> classesToSkip)
      Traverses the object graph with complete node visiting capabilities.
      Parameters:
      root - the root object to start traversal
      classesToSkip - classes to skip during traversal (can be null)
      visitor - visitor that receives detailed node information

    • traverse

      @Deprecated public static void traverse(Object root, Traverser.Visitor visitor)
      Deprecated.
      Use traverse(Object, Set, Consumer) instead.

    • traverse

      @Deprecated public static void traverse(Object root, Class<?>[] skip, Traverser.Visitor visitor)
      Deprecated.
      Use traverse(Object, Set, Consumer) instead.