//  PlanetsMap.java (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2015-01-02  File created.
//  2015-01-02  Last modification.

//  This program works in the same way as Planets.java. 
//  In this version there is no conventional array for storing
//  Planet objects. Instead, the Planet objects are stored into
//  a data structure called HashMap.

//  You will see that it is very easy to search for an object in
//  a HashMap.

import java.util.* ;

class Planet
{
   String  planet_name ;
   double  mean_distance_from_sun ;
   double  circulation_time_around_sun ;
   double  rotation_time_around_own_axis ;
   long    equatorial_radius_in_kilometers ;
   double  mass_compared_to_earth ;
   int     number_of_moons ;

   public Planet( String  given_planet_name,
                  double  given_mean_distance_from_sun,
                  double  given_circulation_time_around_sun,
                  double  given_rotation_time_around_own_axis,
                  long    given_equatorial_radius_in_kilometers,
                  double  given_mass_compared_to_earth,
                  int     given_number_of_moons )
   {
      planet_name  =  given_planet_name ;
      mean_distance_from_sun  =  given_mean_distance_from_sun ;
      circulation_time_around_sun  =  given_circulation_time_around_sun ;
      rotation_time_around_own_axis  =  given_rotation_time_around_own_axis ;
      equatorial_radius_in_kilometers = given_equatorial_radius_in_kilometers ;
      mass_compared_to_earth  =  given_mass_compared_to_earth ;
      number_of_moons  =  given_number_of_moons ;
   }

   public String get_planet_name()
   {
      return  planet_name ;
   }

   public void print_planet_data()
   {
      System.out.print( "\n " + planet_name
                  +  " orbits the sun in average distance of "
                  +  ( mean_distance_from_sun * 149500000 ) + " kilometers."
                  +  "\n It takes "  +  circulation_time_around_sun
                  +  " years for " +  planet_name
                  +  " to go around the sun once. \n The radius of "
                  +  planet_name + " is "
                  +  equatorial_radius_in_kilometers  + " kilometers.\n" ) ;
   }
}

public class  PlanetsMap
{
   public static void main( String[] not_in_use )
   {
      Scanner  keyboard  =  new Scanner( System.in ) ;

      //  First we create a HashMap.

      HashMap<String, Planet>  planet_table  =  new HashMap<String, Planet>() ;

      //  Then we put Key-Object pairs to the table. Each key is a String, and
      //  the objects associated with the keys are Planet objects.

      planet_table.put( "mercury", new Planet(
          "Mercury",  0.387,   0.241,  58.815,  2433,   0.05,  0  ) ) ;

      planet_table.put( "venus", new Planet(
          "Venus",    0.723,   0.615, 224.588,  6053,   0.82,  0  ) ) ;

      planet_table.put( "earth", new Planet(
          "Earth",    1.000,   1.000,   1.000,  6379,   1.00,  1  ) ) ;
      planet_table.put( "mars",  new Planet(
          "Mars",     1.523,   1.881,   1.029,  3386,   0.11,  2  ) ) ;
      planet_table.put( "jupiter",  new Planet(
          "Jupiter",  5.203,  11.861,   0.411, 71370, 317.93, 12  ) ) ;
      planet_table.put( "saturn", new Planet(
          "Saturn",   9.541,  29.457,   0.428, 60369,  95.07, 10  ) ) ;
      planet_table.put( "uranus", new Planet(
          "Uranus",  19.190,  84.001,   0.450, 24045,  14.52,  5  ) ) ;
      planet_table.put( "neptune", new Planet(
          "Neptune", 30.086, 164.784,   0.657, 22716,  17.18,  2  ) ) ;
      planet_table.put( "pluto", new Planet(
          "Pluto",   39.507, 248.35,    6.410,  5700,   0.18,  0  ) ) ;


      System.out.print( "\n This program can give you information about the"
                   + "\n planets in our solar system. Give a planet name: ");

      String  planet_name_from_user  =  keyboard.nextLine().toLowerCase() ;

      // With the method containsKey() we ask if there is a Planet object
      // connected to the the String object pointed by
      // planet_name_from_user.

      if ( planet_table.containsKey( planet_name_from_user ) )
      {
         planet_table.get( planet_name_from_user).print_planet_data() ;

      }
      else
      {
         System.out.print( "\n Sorry, could not find information on \""
                        +  planet_name_from_user  +  "\".\n" ) ;

      }
   }
}

/* NOTES:

The following pages might be useful to read:

http://docs.oracle.com/javase/7/docs/api/java/util/Map.html

http://docs.oracle.com/javase/7/docs/api/java/util/HashMap.html

http://docs.oracle.com/javase/7/docs/technotes/guides/collections/index.html

*/