Circle Model

Circle.java

package demo;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * 圈子成员接口.
 * 
 */
interface CircleMember {
  Long getId();

  String getName();

  // 获取成员对应的用户
  List<User> getCircleUsers(Long circleId);
}

/**
 * 圈子.
 * 
 */
public class Circle {
  // @ManyToMany
  private List<User> users = new ArrayList<User>();

  // @ManyToMany
  private List<Group> groups = new ArrayList<Group>();

  // 获取圈子成员列表.
  public List<CircleMember> getMembers() {
    List<CircleMember> members = new ArrayList<CircleMember>();
    members.addAll(users);
    members.addAll(groups);
    return members;
  }
}

interface CircleService {
  public Circle getCircleById(Long id);

  // 发送圈子消息
  public void sendMessage(Long circleId, Message message);
}

class CircleServiceImpl implements CircleService {

  public Circle getCircleById(Long id) {
    return null;
  }

  public void sendMessage(Long circleId, Message message) {
    Circle circle = getCircleById(circleId);
    // 检测circle != null
    for (CircleMember member : circle.getMembers()) {
      if (member instanceof User) {
        // 如果成员是用户
      } else if (member instanceof Group) {
        // 如果成员是组织机构
      }
      List<User> users = member.getCircleUsers(circleId);
      for (User user : users) {
        doSendMessage(user, message);
      }
    }
  }

  private void doSendMessage(User user, Message message) {
    // TODO
  }
}

/**
 * 用户.
 * 
 */
// @Entity
class User implements CircleMember {
  // 用户加入的圈子
  // @ManyToMany
  private List<Circle> circles = new ArrayList<Circle>();

  public Long getId() {
    return null;
  }

  public String getName() {
    return null;
  }

  public List<User> getCircleUsers(Long circleId) {
    return Arrays.asList(this);
  }

  public List<Circle> getCircles() {
    return circles;
  }
}

/**
 * 分组.
 * 
 * (包括机构、企业)
 * 
 */
// @Entity
class Group implements CircleMember {

  public Long getId() {
    return null;
  }

  public String getName() {
    return null;
  }

  public List<User> getCircleUsers(Long circleId) {
    // TODO 通过角色匹配等方式获取此"分组" 对应的用户
    return null;
  }
}

/**
 * 消息.
 * 
 */
// @Entity
class Message {
}