/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

package opennlp.tools.util;

import java.util.Collection;
import java.util.Iterator;

/**
 * An {@link ObjectStream} implementation that works on a
 * {@link Collection} of {@link E} as source for elements.
 *
 * @param <E> The generic type of the elements.
 */
public class CollectionObjectStream<E> implements ObjectStream<E> {
  private final Collection<E> collection;

  private Iterator<E> iterator;

  public CollectionObjectStream(Collection<E> collection) {
    this.collection = collection;
    reset();
  }

  @Override
  public E read() {
    return iterator.hasNext() ? iterator.next() : null;
  }

  @Override
  public void reset() {
    this.iterator = collection.iterator();
  }

  @Override
  public void close() {
  }
}
