lsdmfocwrule.java

基于词典和最大匹配算法的的中文分词组件

/**
 * 
 */
package org.solol.mmseg.internal;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.solol.mmseg.core.IChunk;
import org.solol.mmseg.core.IRule;

/**
 * @author solo L
 *
 */
public class LSDMFOCWRule implements IRule {
	
	/* (non-Javadoc)
	 * @see org.solol.mmseg.core.IRule#invoke()
	 */
	public final IChunk[] invoke(final IChunk[] chunks) {
		LSDMFOCWRuleComparator[] orderedChunks = new LSDMFOCWRuleComparator[chunks.length];

		for (int i = 0; i < chunks.length; i++) {
			orderedChunks[i] = new LSDMFOCWRuleComparator(chunks[i]);
		}

		Arrays.sort(orderedChunks);

		int index = 0;
		double degreeOfMorphemicFreedom = orderedChunks[index].getChunk().getDegreeOfMorphemicFreedom();

		List list = new ArrayList(1);
		list.add(orderedChunks[index].getChunk());

		index++;

		while (index < orderedChunks.length) {

			if (orderedChunks[index].getChunk().getDegreeOfMorphemicFreedom() == degreeOfMorphemicFreedom) {
				list.add(orderedChunks[index].getChunk());
			} else {
				break;
			}
			index++;
		}

		IChunk[] degreeOfMorphemicFreedomChunks = new IChunk[list.size()];
		list.toArray(degreeOfMorphemicFreedomChunks);

		return degreeOfMorphemicFreedomChunks;
	}
	
	static class LSDMFOCWRuleComparator implements Comparable {

		private IChunk chunk;

		public LSDMFOCWRuleComparator(IChunk chunk) {
			this.chunk = chunk;
		}

		public IChunk getChunk() {
			return chunk;
		}

		public int compareTo(Object obj) {
			IChunk another = ((LSDMFOCWRuleComparator) obj).getChunk();

			double temp = another.getDegreeOfMorphemicFreedom()
					- chunk.getDegreeOfMorphemicFreedom();

			if (temp > 0D) {
				return 1;
			} else if (temp < 0D) {
				return -1;
			} else {
				return 0;
			}
		}
	}

}