meetingvaluefactory.java

来自「100多M的J2EE培训内容」· Java 代码 · 共 104 行

package com.borland.training.meetings.sessions;

import java.util.*;
import javax.ejb.*;
import javax.naming.*;
import com.borland.training.meetings.entities.*;

class MeetingValueFactory {

  private static MeetingValueFactory instance = null;
  private EJBHomeFactory homeFactory;

  private MeetingValueFactory() throws NamingException {
    homeFactory = EJBHomeFactory.getInstance();
  }

  public static MeetingValueFactory getInstance() throws NamingException {
    if(instance == null) {
      instance = new MeetingValueFactory();
    }
    return instance;
  }

  public MeetingValue getMeeting(Long id)
    throws FinderException, NamingException {

    Meeting meeting = findMeeting(id);
    return createValue(meeting);
  }

  public Collection getMeetingsOfAttendee(Long id)
    throws FinderException, NamingException {

    Collection meetings = findMeetingsOfAttendee(id);
    return createValues(meetings);
  }

  public Collection getAllMeetings()
    throws FinderException, NamingException {

    Collection meetings = findAllMeetings();
    return createValues(meetings);
  }

  // Helper method used by the factory or a manager
  public Meeting findMeeting(Long id)
    throws FinderException, NamingException {

    MeetingHome home = (MeetingHome) homeFactory.lookupByLocalEJBReference("Meeting");
    return home.findByPrimaryKey(id);
  }

  // Helper method used by the factory or a manager
  public Collection findMeetingsOfAttendee(Long id)
    throws FinderException, NamingException {

    AttendeeHome home = (AttendeeHome) homeFactory.lookupByLocalEJBReference("Attendee");
    Attendee attendee = home.findByPrimaryKey(id);
    return attendee.getMeetings();
  }

  // Helper method used by the factory or a manager
  public Collection findAllMeetings()
    throws FinderException, NamingException {

    MeetingHome home = (MeetingHome) homeFactory.lookupByLocalEJBReference("Meeting");
    return home.findAll();
  }

  // Helper method used by the factory
  private MeetingValue createValue(Meeting meeting) {
    return new MeetingValue(meeting.getId(),
      meeting.getTopic(),
      meeting.getStartTime(),
      meeting.getFinishTime(),
      meeting.getRoom().getName(),
      getAttendeeIds(meeting));
  }

  // Helper method used by the factory
  private Collection createValues(Collection meetings) {
    Collection meetingValues = new Vector(meetings.size());
    Iterator iterator = meetings.iterator();
    Meeting meeting = null;
    while(iterator.hasNext()) {
      meeting = (Meeting) iterator.next();
      meetingValues.add(createValue(meeting));
    }
    return meetingValues;
  }

  // Helper method used by the factory
  private Collection getAttendeeIds(Meeting meeting) {
    Collection attendees = meeting.getAttendees();
    Collection attendeeIds = new Vector(attendees.size());
    Iterator iterator = attendees.iterator();
    Attendee attendee = null;
    while(iterator.hasNext()) {
      attendee = (Attendee) iterator.next();
      attendeeIds.add(attendee.getId());
    }
    return attendeeIds;
  }
}