AbstractState.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.component.state;

import edu.emory.clir.clearnlp.component.utils.CFlag;
import edu.emory.clir.clearnlp.dependency.DEPNode;
import edu.emory.clir.clearnlp.dependency.DEPTree;
import edu.emory.clir.clearnlp.feature.AbstractFeatureToken;

/**
 * @since 3.0.0
 * @author Jinho D. Choi ({@code jinho.choi@emory.edu})
 */
abstract public class AbstractState<OracleType,LabelType>
{
	protected OracleType[] g_oracle;
	protected DEPTree d_tree;
	protected int     t_size;
	protected CFlag   c_flag;

//	====================================== INITIALIZATION ======================================
	
	public AbstractState() {}
	
	public AbstractState(DEPTree tree, CFlag flag)
	{
		d_tree = tree;
		t_size = tree.size();
		c_flag = flag;
		if (flag != CFlag.COLLECT && flag != CFlag.DECODE) initOracle();
	}
	
//	====================================== ORACLE/LABEL ======================================
	
	protected abstract void initOracle();
	public    abstract void resetOracle();
	
	public OracleType[] getOracle()
	{
		return g_oracle;
	}
	
	protected OracleType getOracle(int id)
	{
		return g_oracle[id];
	}

	/** @return the gold-standard label for the current state. */
	public abstract LabelType getGoldLabel();
	
//	====================================== TREE/NODE ======================================
	
	public DEPTree getTree()
	{
		return d_tree;
	}
	
	public int getTreeSize()
	{
		return t_size;
	}

	/** @return the dependency node specified by the feature token. */
	abstract public DEPNode getNode(AbstractFeatureToken token);
	
	public DEPNode getNode(int id)
	{
		return d_tree.get(id);
	}
	
	/** Called by {@link #getNode(AbstractFeatureToken, DEPTree, int, int, int)}. */
	protected DEPNode getNodeRelation(AbstractFeatureToken token, DEPNode node)
	{
		if (node == null) return null;
		
		if (token.hasRelation())
		{
			switch (token.getRelation())
			{
			case h   : return node.getHead();
			case lmd : return node.getLeftMostDependent();
			case rmd : return node.getRightMostDependent();
			case lnd : return node.getLeftNearestDependent();
			case rnd : return node.getRightNearestDependent();
			case lns : return node.getLeftNearestSibling();
			case rns : return node.getRightNearestSibling();
			
			case h2  : return node.getGrandHead();
			case lmd2: return node.getLeftMostDependent(1);
			case rmd2: return node.getRightMostDependent(1);
			case lnd2: return node.getLeftNearestDependent(1);
			case rnd2: return node.getRightNearestDependent(1);
			case lns2: return node.getLeftNearestSibling(1);
			case rns2: return node.getRightNearestSibling(1);
			}
		}
		
		return node;
	}
	
//	====================================== TRANSITION ======================================
	
	/** Sets the label of the current state, and move to the next state. */
	public abstract void next(LabelType label);
	/** {@code true} if the process should terminate. */
	public abstract boolean isTerminate();
	
//	====================================== HELPER ======================================
	
	public boolean isFirstNode(DEPNode node)
	{
		return node.getID() == 1;
	}
	
	public boolean isLastNode(DEPNode node)
	{
		return node.getID() + 1 == t_size;
	}
}