Java

`Test.java`


class Test {
  public static void main(String[] args) {
    System.out.println("Test");
  }
}

`bash`


>javac Test.java
>java Test
Test

`Index.java`


package test;

public class Index {
  public static void main(String[] args) { 
    TokyoService tokyo = new TokyoService();

    for (String city : tokyo.getCities()) {
      System.out.println(city);
    }

    OsakaService osaka = new OsakaService();
    System.out.println(osaka.getCity(0));
  }
}

`IPrefecture`


package test;

public interface IPrefecture {
  String[] getCities();
  //Overload
  String getCity(int id);
}

`TokyoService`



package test;

public class TokyoService implements IPrefecture {
  static final String[] cities = {"Chuo-ku", "Naniwa Ward"};
	public TokyoService() {
    System.out.println("Osaka");
	}

	@Override
	public String[] getCities() {
		return cities;
	}

	@Override
	public String getCity(int id) {
		return cities[id];
	}
}

`OsakaService`


package test;

public class OsakaService implements IPrefecture {
  static final String[] cities = {"Shibuya Ward", "Shinjuku ward"};
  public OsakaService() {
    System.out.println("Osaka");
  }

  @Override
  public String[] getCities() {
    return cities;
  }

  @Override
  public String getCity(int id) {
    return cities[id];
  }
}