content: package edu.berkeley.nlp.lm.map;
  
  import java.util.Arrays;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.Map.Entry;
  
  import edu.berkeley.nlp.lm.WordIndexer;
  import edu.berkeley.nlp.lm.collections.Iterators;
  import edu.berkeley.nlp.lm.util.Logger;
  
  /**
   * Wraps an NgramMap as an Iterable, so it is easy to iterate over the n-grams
   * and associated values. Using this interface is a little inefficient due to
   * the boxing and temporary object allocation necessary to conform to Java's
   * interfaces.
   * 
   * @author adampauls
   * 
   * @param <V>
   * @param <W>
   */
  public class NgramIterableWrapper<W, V> implements Iterable<java.util.Map.Entry<List<W>, V>>
  {
  
  	private final NgramsForOrderIterableWrapper<W, V>[] ngramsForOrder;
  
  	public NgramIterableWrapper(final NgramMap<V> map, final WordIndexer<W> wordIndexer) {
  		this(map, wordIndexer, map.getMaxNgramOrder());
  	}
  
  	/**
  	 * 
  	 * @param map
  	 * @param wordIndexer
  	 * @param maxOrder
  	 *            this is 1-based (i.e. 1 means keep unigrams but not bigrams)
  	 */
  	public NgramIterableWrapper(final NgramMap<V> map, final WordIndexer<W> wordIndexer, final int maxOrder) {
  		@SuppressWarnings("unchecked")
  		final NgramsForOrderIterableWrapper<W, V>[] maps = new NgramsForOrderIterableWrapper[maxOrder];
  		ngramsForOrder = maps;
  		for (int ngramOrder = 0; ngramOrder < maxOrder; ++ngramOrder) {
  			ngramsForOrder[ngramOrder] = new NgramsForOrderIterableWrapper<W, V>(map, wordIndexer, ngramOrder);
  		}
  	}
  
  	@Override
  	public Iterator<Entry<List<W>, V>> iterator() {
  		final Iterators.Transform<NgramsForOrderIterableWrapper<W, V>, Iterator<java.util.Map.Entry<List<W>, V>>> transform = new Iterators.Transform<NgramsForOrderIterableWrapper<W, V>, Iterator<java.util.Map.Entry<List<W>, V>>>(
  			Arrays.asList(ngramsForOrder).iterator())
  		{
  
  			@Override
  			protected Iterator<java.util.Map.Entry<List<W>, V>> transform(final NgramsForOrderIterableWrapper<W, V> next) {
  				return next.iterator();
  			}
  		};
  		return new Iterators.IteratorIterator<Map.Entry<List<W>, V>>(transform);
  
  	}
  
  	public long size() {
  		long size = 0;
  		for (final NgramsForOrderIterableWrapper<W, V> map : ngramsForOrder) {
  			size += map.size();
  		}
  		if (size > Integer.MAX_VALUE) Logger.warn(NgramMapWrapper.class.getSimpleName() + " doesn't like maps with size greater than Integer.MAX_VALUE");
  		return (int) size;
  	}
  }
  