documentreference.java

来自「一个使用的搜索引擎」· Java 代码 · 共 51 行

package ir.vsr;

import java.io.*;

/** A simple data structure for storing a reference to a document file
 *  that includes information on the length of its document vector.
 *  The goal is to have a lightweight object to store in an inverted index
 *  without having to store an entire Document object.
 *
 * @author Ray Mooney
 */

public class DocumentReference {
    /** The file where the referenced document is stored. */
    public File file = null;
    /** The length of the corresponding Document vector. */
    public double length = 0.0;

    public DocumentReference(File file, double length) {
	this.file = file;
	this.length = length;
    }

    /** Create a reference to this document, initializing its length to 0 */
    public DocumentReference(FileDocument doc) {
	this(doc.file, 0.0);
    }

    public String toString() {
	return file.getName();
    }

    /** Get the full Document for this Document reference by recreating it
	with the given docType and stemming 
    */
    public Document getDocument(short docType, boolean stem) {
	Document doc = null;
	switch(docType) {
	case DocumentIterator.TYPE_TEXT:
	    doc = new TextFileDocument(file, stem);
	    break;
	case DocumentIterator.TYPE_HTML:
	    doc = new HTMLFileDocument(file, stem);
	    break;
	}
	return doc;
    }
	

}