com.techempower.js.legacy.Visitor Maven / Gradle / Ivy

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package com.techempower.js.legacy;

/**
 * An iterator-like object that traverses objects encountered by 
 * JavaScriptWriter.  The flow of calls to a visitor is:
 *
 * 
 * {@code isArray()} - if this returns {@code true}, then always skip step 4
 * {@code hasNext()} - if this returns {@code false}, then stop
 * {@code next()}
 * {@code name()}
 * {@code value()}
 * go to step 2
 * 
 *
 * @see LegacyJavaScriptWriter
 * @see VisitorFactory
 */
public interface Visitor
{
  /**
   * Returns {@code true} if there are more nodes to visit in the object.
   */
  boolean hasNext();

  /**
   * Returns {@code true} if the object should be treated as an array.
   */
  boolean isArray();

  /**
   * Returns the name of the current node.  Only applies to non-array visitors.
   */
  String name();

  /**
   * Advances to the next node.
   */
  void next();

  /**
   * Returns the value of the current node.
   */
  Object value();
}