operator.java

java实现的全文搜索引擎

/**
 * Decorator Pattern
 */
package cn.edu.nju.software.ruse;

import java.io.File;
import java.util.HashSet;
import java.util.Map;

/**
 * @author spring
 *
 */
public abstract class Operator {

	String desription = "Unknown Operand";

	int PRI;
	
	public final static int PRI_LEFTPARENTHESES = 40;
	
	public final static int PRI_NOT = 30;
	
	public final static int PRI_AND = 20;
	
	public final static int PRI_OR = 10;
	
	public final static int PRI_RIGHTPARENTHESES = 0;
	
	public final static int PRI_END = -1;
	
	public final static int PRI_MODTIME = 50;
	
	public final static int PRI_FILESIZE = 50;
	
	public final static int PRI_FILENAME = 50;
	
	public final static int PRI_FILECONTENTS = 50;
	
	public final static int PRI_PROXIMITY = 50;
	
	public String getDesription() {
		return desription;
	}
	
	public abstract int getPRI();
	
//	public abstract Operator createOperator(String operator);
//	{
//		if(operator.equals("(")) {
//			return new Operator_LeftParentheses();
//		}else if(operator.equals("NOT")) {
//			return new Operator_NOT();
//		}else if(operator.equals("AND")) {
//			return new Operator_OR();
//		}else if(operator.equals(")")) {
//			return new Operator_RightParentheses();
//		}else {
//			//System.err.println("@Operator The operator is not difined!");
//			return null;
//		}
//	}
}