retrieval.java

这是一个用于测试用的搜索引擎的案例

package ir.vsr;

/** A lightweight object for storing information about a retrieved Document.
 *
 * @author Ray Mooney
 */

public class Retrieval implements java.lang.Comparable {

    /** A reference to the Document being retrieved */
    public DocumentReference docRef;
    /** The score given to this document by a retrieval engine. Higher scores
     * mean it is more relevant to the query */
    public double score;

    /** Create a retrieval with these values */
    public Retrieval (DocumentReference docRef, double score) {
	this.docRef = docRef;
	this.score = score;
    }

    /** Compares this Retrieval to another for sorting from best to worst.
     *	@param obj The Retrieval to compare with.
     *  @return -1 if better than obj, 0 if same, 1 if worse than obj
     * since this will produce a descending sort from best to worst.
     * @see java.util.Arrays.sort
     */
    public int compareTo(Object obj) {
	Retrieval retrieval = (Retrieval)obj;
	if (score == retrieval.score) 
	    return 0;
	else if (score > retrieval.score) 
	    return -1;
	else return 1;
    }
		
}