text: 
  #ifndef AMANZI_OPERATOR_PDE_TESTMHD_HH_
  #define AMANZI_OPERATOR_PDE_TESTMHD_HH_
  
  // TPLs
  #include "Teuchos_RCP.hpp"
  #include "Teuchos_ParameterList.hpp"
  
  // Amanzi
  #include "exceptions.hh"
  #include "Tensor.hh"
  #include "CompositeVector.hh"
  
  // Amanzi::Operators
  #include "BilinearForm.hh"
  #include "Operator.hh"
  #include "OperatorDefs.hh"
  #include "PDE_HelperDiscretization.hh"
  #include "Schema.hh"
  
  namespace Amanzi {
  namespace Operators {
  
  class PDE_FirstOrderPoisson: public PDE_HelperDiscretization {
   public:
  //Constructor
    PDE_FirstOrderPoisson(const Teuchos::RCP<const AmanziMesh::Mesh>& mesh);//,Teuchos::ParameterList& plist);
  //Destructor
  ~PDE_FirstOrderPoisson(){};
  //   // -- creation of an operator
     using PDE_HelperDiscretization::UpdateMatrices;
     virtual void UpdateMatrices(const Teuchos::Ptr<const CompositeVector>& u,
                                 const Teuchos::Ptr<const CompositeVector>& p) override;
  
  //   // -- postprocessing: calculated stress u from displacement p
    virtual void UpdateFlux(const Teuchos::Ptr<const CompositeVector>& p,
                            const Teuchos::Ptr<CompositeVector>& u) override {};
  
  //These are accessors
  Teuchos::RCP<CompositeVectorSpace> GetuCVS(){return u_cvs_;};
  Teuchos::RCP<CompositeVectorSpace> GetpCVS(){return p_cvs_;};
  //
  Teuchos::RCP<Operator> GetMassGlobalOp(){return mass_global_op_;};
  Teuchos::RCP<Operator> GetDivGlobalOp(){return div_global_op_;};
  //
  Teuchos::RCP<Op> GetMassLocalOp(){return mass_local_op_;};
  Teuchos::RCP<Op> GetDivLocalOp(){return div_local_op_;};
  //The Space of Velocities 
  Teuchos::RCP<CompositeVectorSpace> u_cvs_;
  //The Space of Pressures
  Teuchos::RCP<CompositeVectorSpace> p_cvs_;
  //Containers of the local matrices
  Teuchos::RCP<Op> mass_local_op_;
  Teuchos::RCP<Op> div_local_op_;
  //Global Operators
  Teuchos::RCP<Operator> mass_global_op_;
  Teuchos::RCP<Operator> div_global_op_;
  };
  
  }  // namespace Operators
  }  // namespace Amanzi
  
  #endif