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SnappyData store based off Pivotal GemFireXD

There is a newer version: 2.0-BETA

/*
 * Copyright (c) 2010-2015 Pivotal Software, Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License. You
 * may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License. See accompanying
 * LICENSE file.
 */
package com.gemstone.gemfire.distributed;

/**
 * Members of the distributed system can fill one or more user defined roles.
 * A role is metadata that describes how the member relates to other members
 * or what purpose it fills. 
 *
 * Roles are specified when 
 * connecting to the {@link DistributedSystem}.
 *
 * @author Kirk Lund
 * @since 5.0
 */
public interface Role extends Comparable {
  
  /** 
   * Returns the name of this role. 
   *
   * @return user-defined string name of this role
   */
  public String getName();
  
  /** 
   * Returns true if this role is currently present in distributed system.
   * If true, then at least one member in the system is configured with this
   * role, regardless of whether or not that member has a cache.
   *
   * @return true if this role is currently present in distributed system
   */
  public boolean isPresent();
  
  /** 
   * Returns the count of members currently filling this role. These members
   * may or may not have a cache.
   *
   * @return number of members in system currently filling this role
   */
  public int getCount();
}