content: /*
   * Copyright 2022 Alibaba Group Holding Limited.
   *
   * 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.
   */
  
  package com.alibaba.graphscope.ds.adaptor;
  
  import com.alibaba.graphscope.ds.Vertex;
  
  public interface Nbr<VID_T, EDATA_T> {
      String type();
  
      /**
       * Get the neighboring vertex.
       *
       * @return vertex.
       */
      Vertex<VID_T> neighbor();
  
      /**
       * Get the edge data.
       *
       * @return edge data.
       */
      EDATA_T data();
  
      Nbr<VID_T, EDATA_T> inc();
  
      boolean eq(Nbr<VID_T, EDATA_T> rhs);
  
      Nbr<VID_T, EDATA_T> dec();
  }
  