/*

  * #%L

  * SimpleMongoIteratorImpl.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.client;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.Iterator;

 import java.util.List;

 import com.allanbank.mongodb.MongoIterator;

 import com.allanbank.mongodb.bson.Document;

 /**

  * Iterator over the results of fixed collection.

  * 

  * @param <T>

  *            The type being iterated.

  * 

  * @api.no This class is <b>NOT</b> part of the drivers API. This class may be

  *         mutated in incompatible ways between any two releases of the driver.

  * @copyright 2011-2013, Allanbank Consulting, Inc., All Rights Reserved

  */

 public class SimpleMongoIteratorImpl<T> implements MongoIterator<T> {

     /** The wrapped iterator. */

     private final Iterator<T> myIterator;

     /**

      * Create a new SimpleMongoIteratorImpl.

      * 

      * @param wrapped

      *            The collection to turn into a {@link MongoIterator}.

      */

     public SimpleMongoIteratorImpl(final Collection<T> wrapped) {

         myIterator = wrapped.iterator();

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return the null as this cursor cannot be restarted.

      * </p>

      */

     @Override

     public Document asDocument() {

         return null;

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to do nothing.

      * </p>

      */

     @Override

     public void close() {

         // Nothing.

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return -1.

      * </p>

      */

     @Override

     public int getBatchSize() {

         return -1;

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return true if there are more documents.

      * </p>

      */

     @Override

     public boolean hasNext() {

         return myIterator.hasNext();

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return this iterator.

      * </p>

      */

     @Override

     public Iterator<T> iterator() {

         return this;

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return the next document from the query.

      * </p>

      * 

      * @see java.util.Iterator#next()

      */

     @Override

     public T next() {

         return myIterator.next();

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to throw an {@link UnsupportedOperationException}.

      * </p>

      * 

      * @see java.util.Iterator#remove()

      */

     @Override

     public void remove() {

         throw new UnsupportedOperationException(

                 "Cannot remove a document via a MongoDB iterator.");

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to do nothing as this iterator only supports single batch

      * results.

      * </p>

      */

     @Override

     public void setBatchSize(final int batchSize) {

         // Nothing.

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to do nothing as this iterator only supports single batch

      * results.

      * </p>

      */

     @Override

     public void stop() {

         // Nothing.

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return the remaining elements as a array.

      * </p>

      */

     @Override

     public Object[] toArray() {

         final List<T> remaining = toList();

         return remaining.toArray();

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return the remaining elements as a array.

      * </p>

      */

     @Override

     public <S> S[] toArray(final S[] to) {

         final List<T> remaining = toList();

         return remaining.toArray(to);

     }

     /**

      * {@inheritDoc}

      * <p>

      * Overridden to return the remaining elements as a list.

      * </p>

      */

     @Override

     public List<T> toList() {

         final List<T> remaining = new ArrayList<T>();

         while (hasNext()) {

             remaining.add(next());

         }

         return remaining;

     }

 }