InMemoryPredicateManager.java

/*
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation; either version 2 of the License, or (at your option) any later
 * version. You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

package org.aitools.programd.predicates;

import java.util.HashMap;
import java.util.Map;

import org.aitools.programd.Core;

/**
 * This is a generic PredicateManager that doesn't store anything anywhere; mostly useful for testing, or for situations
 * where there's no need to remember user predicates, dialogue history, etc. across restarts of the server.
 * 
 * @author <a href="mailto:noel@aitools.org">Noel Bush</a>
 */
public class InMemoryPredicateManager extends PredicateManager {

  /** A map of userids to botid-keyed predicate maps. */
  private Map<String, Map<String, Map<String, String>>> _predicateMaps = new HashMap<String, Map<String, Map<String, String>>>();

  /**
   * Creates a new InPredicateManager with the given Core as owner.
   * 
   * @param core the Core that owns this
   */
  public InMemoryPredicateManager(Core core) {
    super(core);
  }

  /**
   * Does nothing.
   * 
   * @see org.aitools.programd.predicates.PredicateManager#dumpPredicates()
   */
  @Override
  protected void dumpPredicates() {
    // Do nothing.
  }

  /**
   * Does nothing.
   * 
   * @see org.aitools.programd.predicates.PredicateManager#initialize()
   */
  @Override
  public void initialize() {
    // No initialization necessary.
  }

  /**
   * @see org.aitools.programd.predicates.PredicateManager#loadPredicate(java.lang.String, java.lang.String,
   *      java.lang.String)
   */
  @Override
  public String loadPredicate(String name, String userid, String botid) throws NoSuchPredicateException {
    Map<String, Map<String, String>> userPredicates;
    if (this._predicateMaps.containsKey(userid)) {
      userPredicates = this._predicateMaps.get(userid);
    }
    else {
      userPredicates = new HashMap<String, Map<String, String>>();
      this._predicateMaps.put(userid, userPredicates);
    }

    Map<String, String> predicates;
    if (userPredicates.containsKey(botid)) {
      predicates = userPredicates.get(botid);
    }
    else {
      predicates = new HashMap<String, String>();
      userPredicates.put(botid, predicates);
    }

    if (!predicates.containsKey(name)) {
      throw new NoSuchPredicateException(name);
    }
    return predicates.get(name);
  }
}