Bigram.java

/**
 * Copyright 2014, Emory University
 * 
 * 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.
 */
package edu.emory.clir.clearnlp.collection.ngram;

import java.io.Serializable;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import edu.emory.clir.clearnlp.collection.pair.ObjectDoublePair;
import edu.emory.clir.clearnlp.collection.pair.ObjectIntPair;

public class Bigram<T1,T2> implements Serializable
{
	private static final long serialVersionUID = 4856975632981517711L;
	private Map<T1,Unigram<T2>> g_map;
	
	public Bigram()
	{
		g_map = new HashMap<>();
	}
	
	public void add(T1 key1, T2 key2)
	{
		add(key1, key2, 1);
	}
	
	public void add(T1 key1, T2 key2, int inc)
	{
		g_map.computeIfAbsent(key1, k -> new Unigram<>()).add(key2, inc);
	}
	
	public ObjectDoublePair<T2> getBest(T1 key1)
	{
		Unigram<T2> map = g_map.get(key1);
		return (map != null) ? map.getBest() : null;
	}
	
	public Set<T1> getBigramSet()
	{
		return g_map.keySet();
	}
	
	public Set<T2> getUnigramSet(T1 key1)
	{
		Unigram<T2> map = g_map.get(key1);
		return (map != null) ? map.keySet() : null;
	}
	
	public List<ObjectIntPair<T2>> toList(T1 key1, int cutoff)
	{
		Unigram<T2> map = g_map.get(key1);
		return (map != null) ? map.toList(cutoff) : null;
	}
	
	public List<ObjectDoublePair<T2>> toList(T1 key1, double threshold)
	{
		Unigram<T2> map = g_map.get(key1);
		return (map != null) ? map.toList(threshold) : null;
	}
}