dbsearchmanager.java

一个用jsp技术实现的新闻发布系统

package net.ijsp.news.search.database;

import org.apache.lucene.document.*;
import org.apache.lucene.analysis.cn.*;
import org.apache.lucene.analysis.*;
import org.apache.lucene.analysis.standard.*;
import org.apache.lucene.index.*;
import org.apache.lucene.store.*;

import java.io.*;
import net.ijsp.news.search.SearchManager;
import net.ijsp.news.news.News;
import net.ijsp.news.database.LoadProp;

public class DbSearchManager implements SearchManager {

	private boolean searchEnabled = true;
	private boolean busy = false;
	private boolean autoIndexEnabled = true;
	private static String indexPath = null;					// 索引路径
	protected static Analyzer analyzer = new ChineseAnalyzer();			// 中文检索
	
    public boolean isSearchEnabled() {
        return searchEnabled;
    }

	public void setSearchEnabled(boolean searchEnabled) {
        this.searchEnabled = searchEnabled;
    }

	public boolean isBusy() {
        return busy;
    }

	public boolean isAutoIndexEnabled() {
        return autoIndexEnabled;
    }

    public synchronized void addToIndex(News news) {
        if (!searchEnabled) {
            return;
        }
        IndexWriter writer = null;
        try {
            writer = getWriter(false);
			
			addMessageToIndex(news.getNewsFile(),news.getTitle(),news.getContent(),
	            Long.toString(news.getDate()),writer,news.getBoardID());

        }catch (IOException ioe) {
            ioe.printStackTrace();
        }finally{
            try {
				writer.close(); 
			}catch (Exception e) {
			}
        }
    }

	private static IndexWriter getWriter(boolean create) throws IOException {
        if (indexPath == null) {
			// 获取全文检索数据路径
           LoadProp loadProp = new LoadProp();
		   loadProp = loadProp.prop();
		   indexPath = loadProp.getIndexPath();
         }

        IndexWriter writer = null;

        if (create) {
            try {
                writer = new IndexWriter(indexPath, analyzer, true);
            }catch (Exception e) {
                System.err.println("ERROR: Failed to create a new index writer.");
                e.printStackTrace();
            }
        } else {
            if (indexExists(indexPath)) {
                try {
                    writer = new IndexWriter(indexPath, analyzer, false);
                }catch (Exception e) {
                    System.err.println("ERROR: Failed to open an index writer.");
                    e.printStackTrace();
                }
            }else {
				try {
                    writer = new IndexWriter(indexPath, analyzer, true);
                }catch (Exception e) {
                    System.err.println("ERROR: Failed to create a new inex writer.");
					
                    e.printStackTrace();
                }
            }
        }
        return writer;
    }

	/**
	* 分析检索数据路径是否正确
	*/ 
	private static boolean indexExists(String indexPath) {
        File segments = new File(indexPath + File.separator + "segments");
        return segments.exists();
    }

	/**
	* 将数据存入全文索引文件中
	*/
	protected final void addMessageToIndex(String newsPath, String subject, String body,
            String creationDate, IndexWriter writer,int newsClass) throws IOException {
        if (writer == null) {
            return;
        }

        Document doc = new Document();
        doc.add(Field.UnIndexed("newsPath",newsPath));
        doc.add(Field.Text("subject", subject));
        doc.add(Field.UnStored("body", body));
        doc.add(new Field("creationDate",creationDate,false, true, false));
		doc.add(new Field("newsClass", Integer.toString(newsClass), false, true, false));
        writer.addDocument(doc);
    }

}