fieldfilter.java

一个用jsp技术实现的新闻发布系统

package net.ijsp.news.search;

/**
*  搜索
*  @author: ccjsmile
*  Company: http://www.ijsp.net
*  Copyright: Copyright (c) 2003
*  @version 1.0 beta
*/

import java.util.BitSet;
import java.io.IOException;

import org.apache.lucene.index.Term;
import org.apache.lucene.index.TermDocs;
import org.apache.lucene.index.IndexReader;

public class FieldFilter extends org.apache.lucene.search.Filter {

    private Term [] searchTerms;

    public FieldFilter(String field, String [] values) {
        searchTerms = new Term[values.length];
        for (int i=0; i<values.length; i++) {
            searchTerms[i] = new Term(field, values[i]);
        }
    }

    public FieldFilter(String field, String value) {
        this(field, new String[] { value });
    }

    public BitSet bits(IndexReader reader) throws IOException {
        //Create a new BitSet with a capacity equal to the size of the index.
        BitSet bits = new BitSet(reader.maxDoc());
        //Match all search terms.
        for (int i=0; i < searchTerms.length; i++) {
            //Get an enumeration of all the documents that match the specified
            //field value.
            TermDocs matchingDocs = reader.termDocs(searchTerms[i]);
            try {
                if (matchingDocs != null) {
                    while(matchingDocs.next()) {
                        bits.set(matchingDocs.doc());
                    }
                }
            }
            finally {
                if (matchingDocs != null) {
                    matchingDocs.close();
                }
            }
        }
        return bits;
    }
}