graph.h

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#ifndef SINGA_UTILS_GRAPH_H_
#define SINGA_UTILS_GRAPH_H_

#include <stack>
#include <string>
#include <map>
#include <vector>

namespace singa {

class Node {
 public:
  explicit Node(std::string name);
  Node(const std::string& name, const std::string& origin, int id, void* proto);
  ~Node() {}  // the proto field is deleted outside by other functions
  void AddDstNode(Node* dstnode);
  void AddSrcNode(Node* srcnode);
  void RemoveDstNode(Node* dst);
  void RemoveSrcNode(Node* src);

  std::string name = "";
  std::string origin = "";
  int partition_id = 0;
  void* proto = nullptr;
  std::vector<Node*> srcnodes;
  std::vector<Node*> dstnodes;
};

class Graph {
 public:
  Graph() {}
  ~Graph();
  inline const std::vector<Node*>& nodes() const {
    return nodes_;
  }
  inline Node* node(const std::string& name) const {
    return name2node_.at(name);
  }
  void AddNode(Node* node);
  Node* AddNode(const std::string& name);
  void AddEdge(Node* srcnode, Node* dstnode);
  void AddEdge(const std::string& src, const std::string& dst);
  void RemoveEdge(Node* src, Node* dst);
  void RemoveEdge(const std::string &src, const std::string& dst);
  std::string ToJson() const;
  std::string ToJson(const std::map<std::string, std::string>& info) const;
  void Sort();

 private:
  std::vector<Node*> nodes_;
  std::map<std::string, Node*> name2node_;
};

}  // namespace singa

#endif  // SINGA_UTILS_GRAPH_H_