I've just started using hibernate and I'm trying to map walking distance between two coordinates into a hashmap, There can be many connections from one "FromCoordinate" to another "ToCoordinate". I'm not sure if i've implemented this correctly, What annotations do i need to map this MashMap? Thanks
HashMap> coordWalkingConnections = new HashMap>();
@Entity
@Table(name = "COORDCONNECTIONS")
public class CoordinateConnection implements Serializable{
    private static final long serialVersionUID = -1624745319005591573L;
    /** auto increasing id number */
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID")
    @id
    private int id;
    @Embedded
    public FromCoordinate fromCoord;
    @Embedded
    public ToCoordinate toCoord;
HashMap<FromCoordinate, ArrayList<ToCoordinate >> coordWalkingConnections = new HashMap<FromCoordinate, ArrayList<ToCoordinate >>();
}
public class FromCoordinate implements ICoordinate
{
    @Column(name = "FROM_LAT")
    private double latitude;
    @Column(name = "FROM_LNG")
    private double longitude;
}
public class ToCoordinate implements ICoordinate
{
    @Column(name = "TO_LAT")
    private double latitude;
    @Column(name = "TO_LNG")
    private double longitude;
    @Column(name = "DISTANCE")
    private double distance;
}
DATABASE STRUCTURE
id  FROM_LAT    FROM_LNG    TO_LAT      TO_LNG      Dist
1   43.352669   -6.264341   43.350012   -6.260653   0.38
2   43.352669   -6.264341   43.352669   -6.264341   0.00
3   46.352669   -6.264341   43.353373   -6.262013   0.17
4   47.352465   -6.265865   43.351290   -6.261200   0.25
5   45.452578   -6.265768   43.352788   -6.264396   0.01
6   45.452578   -6.265768   45.782788   -6.234523   0.01
    .....
    ...
    .
Example HashMap for HashMap<Coordinate, ArrayList<Coordinate>>
<KEY{43.352669  -6.264341}, Arraylist VALUES{(43.350012,-6.260653,0.383657),  (43.352669, -6.264341, 0.000095), (43.353373, -6.262013,  0.173201)}>
<KEY{47.352465  -6.265865}, Arraylist VALUES{(43.351290,-6.261200,0.258781)}>
<KEY{45.452578  -6.265768}, Arraylist VALUES{(43.352788,-6.264396,0.013726),(45.782788,-6.234523,0.017726)}>