securefiltersearchable.java

关于Ultraseek的一些用法,刚初学,所以都是比较简单

/* -*- mode:java; indent-tabs-mode:nil; c-basic-offset:2 -*-
 *
 *  $RCSFile$ $Revision: 1.5 $ $Date: 2006/01/25 16:56:21 $
 *
 *  Copyright (c) 2004 Autonomy Corp.  All Rights Reserved.
 *  Permission to use, copy, modify, and distribute this file is hereby
 *  granted without fee, provided that the above copyright notice appear
 *  in all copies.
 */

import java.io.IOException;
import java.util.ArrayList;
import java.lang.Math;

import com.ultraseek.xpa.search.*;

/**
 * Silently removes disallowed <code>SearchResult</code>s from a
 * <code>SearchResultList</code>.
 * <p>
 * <code>GuardingSearchable</code> throws a <code>SecurityException</code>
 * for each disallowed <code>SearchResult</code>.  
 * This enables your application to take appropriate action for 
 * disallowed results.
 * <p>
 * Possible actions your application can take are:
 * <ul>
 * <li>Totally ignore the disallowed <code>SearchResult</code>.
 * <li>Display a message ("You must login to view all results").
 * <li>Display a filtered version of the result (title only, no URL, etc.)
 * <li>Display the result with a "lock" icon.
 * </ul>
 * <p>
 * This <code>Searchable</code> ignores disallowed results from
 * <code>GuardingSearchable</code> by silently removing them
 * from the <code>SearchResultList</code>.
 * <p>
 * Note that result counts are dynamic and will change until the entire
 * search result list is processed.
 * <p>
 * This sample also demonstrates how to implement a <code>Searchable</code> that
 * performs filtering on a <code>SeachResultList</code>.
 *
 * @since XPA2.2
 */
public class SecureFilterSearchable
  extends SearchableWrapper
{
  public SecureFilterSearchable(Searchable base) {
    super(base);
  }

  public SearchResultList search(Query q) 
    throws QueryNotSupportedException, IOException {
    return new ResultList(getSearchable().search(q));
  }

  public class ResultList
    extends SearchResultListWrapper
  {
    private ArrayList allowedResults = new ArrayList();   // Results that are allowed
    private int baseResultsRead = 0;                      // How far we've read
    private int disallowedCount = 0;                      // how many were disallowed

    // NOTE: baseResultsRead == allowedResults.size() + disallowedResults

    public ResultList(SearchResultList base) {
      super(base);
    }

    public synchronized Object get(int n) {

      // Fetch results until we find the n'th allowed result.
      while ((n + 1) > allowedResults.size()) {
        int cursor = baseResultsRead++;
        try {
          Object res = baseResultList.get(cursor);
          allowedResults.add(res);
        } catch (SecurityException se) {
          disallowedCount++;
        }
      }
      return allowedResults.get(n);
    }

    public int size() {
      return (Math.max(baseResultList.size() - baseResultsRead,0) 
              + allowedResults.size());
    }

    public int getResultCount()
      throws IOException {
      return (Math.max(baseResultList.getResultCount() - baseResultsRead,0)
              + allowedResults.size());
    }

    public int getDisallowedSize() {
      return disallowedCount;
    }

    public int getAllowedSize() {
      return allowedResults.size();
    }

  }

}