/*
    * #%L
    * VisitorAdapter.java - mongodb-async-driver - Allanbank Consulting, Inc.
    * %%
    * Copyright (C) 2011 - 2014 Allanbank Consulting, Inc.
    * %%
    * 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
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * 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.
   * #L%
   */
  
  package com.allanbank.mongodb.bson;
  
  import java.util.List;
  
  import com.allanbank.mongodb.bson.element.ObjectId;
  
  /**
   * VisitorAdapter provides a helper for {@link Visitor} implementations that are
   * only interested in a subset of the elements within a document.
   * <p>
   * This implementation will walk the entire tree of elements. Derived classes
   * need only override the methods of interest. Derived classes should be careful
   * to always call the {@code super} implementation of the following methods to
   * ensure they do not break the document walking. Calling {@code super} for all
   * methods is encouraged.
   * <ul>
   * <li> {@link #visit(List)}</li>
   * <li> {@link #visitArray(String, List)}</li>
   * <li> {@link #visitDocument(String, List)}</li>
   * <li> {@link #visitJavaScript(String, String, Document)}</li>
   * </ul>
   * </p>
   * <p>
   * As a further aid to {@link Visitor} implementations only interested in the
   * names of elements, this class will call the {@link #visitName(String)} method
   * for each element visited.
   * </p>
   * 
   * @api.yes This class is part of the driver's API. Public and protected members
   *          will be deprecated for at least 1 non-bugfix release (version
   *          numbers are &lt;major&gt;.&lt;minor&gt;.&lt;bugfix&gt;) before being
   *          removed or modified.
   * @copyright 2013, Allanbank Consulting, Inc., All Rights Reserved
   */
  public class VisitorAdapter implements Visitor {
  
      /**
       * Creates a new VisitorAdapter.
       */
      public VisitorAdapter() {
          super();
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to iterate over the elements of the document.
       * </p>
       */
      @Override
      public void visit(final List<Element> elements) {
          for (final Element element : elements) {
              element.accept(this);
          }
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to visit the name of the element and then iterate over the
       * elements of the array.
       * </p>
       */
      @Override
      public void visitArray(final String name, final List<Element> elements) {
          visitName(name);
          for (final Element element : elements) {
              element.accept(this);
          }
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to visit the name of the element.
       * </p>
       */
      @Override
      public void visitBinary(final String name, final byte subType,
             final byte[] data) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitBoolean(final String name, final boolean value) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitDBPointer(final String name, final String databaseName,
             final String collectionName, final ObjectId id) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element and then iterate over the
      * elements of the document element.
      * </p>
      */
     @Override
     public void visitDocument(final String name, final List<Element> elements) {
         visitName(name);
         for (final Element element : elements) {
             element.accept(this);
         }
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitDouble(final String name, final double value) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitInteger(final String name, final int value) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitJavaScript(final String name, final String code) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitJavaScript(final String name, final String code,
             final Document scope) {
         visitName(name);
         scope.accept(this);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitLong(final String name, final long value) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitMaxKey(final String name) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitMinKey(final String name) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitMongoTimestamp(final String name, final long value) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitNull(final String name) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitObjectId(final String name, final ObjectId id) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitRegularExpression(final String name, final String pattern,
             final String options) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitString(final String name, final String value) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitSymbol(final String name, final String symbol) {
         visitName(name);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to visit the name of the element.
      * </p>
      */
     @Override
     public void visitTimestamp(final String name, final long timestamp) {
         visitName(name);
     }
 
     /**
      * Extension point for {@link Visitor} implementation only interested in the
      * name of the elements.
      * 
      * @param name
      *            The name of the element.
      */
     protected void visitName(final String name) {
         // Nothing. Extension point.
     }
 }