// onjava/Countries.java

// (c)2016 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://mindviewinc.com/Books/OnJava/ for more book information.

// "Flyweight" Maps and Lists of sample data

// {java onjava.Countries}

package onjava;

import java.util.*;

public class Countries {

public static final String[][] DATA = {

// Africa

{"ALGERIA","Algiers"}, {"ANGOLA","Luanda"},

{"BENIN","Porto-Novo"}, {"BOTSWANA","Gaberone"},

{"BURKINA FASO","Ouagadougou"},

{"BURUNDI","Bujumbura"},

{"CAMEROON","Yaounde"}, {"CAPE VERDE","Praia"},

{"CENTRAL AFRICAN REPUBLIC","Bangui"},

{"CHAD","N'djamena"}, {"COMOROS","Moroni"},

{"CONGO","Brazzaville"}, {"DJIBOUTI","Dijibouti"},

{"EGYPT","Cairo"}, {"EQUATORIAL GUINEA","Malabo"},

{"ERITREA","Asmara"}, {"ETHIOPIA","Addis Ababa"},

{"GABON","Libreville"}, {"THE GAMBIA","Banjul"},

{"GHANA","Accra"}, {"GUINEA","Conakry"},

{"BISSAU","Bissau"},

{"COTE D'IVOIR (IVORY COAST)","Yamoussoukro"},

{"KENYA","Nairobi"}, {"LESOTHO","Maseru"},

{"LIBERIA","Monrovia"}, {"LIBYA","Tripoli"},

{"MADAGASCAR","Antananarivo"}, {"MALAWI","Lilongwe"},

{"MALI","Bamako"}, {"MAURITANIA","Nouakchott"},

{"MAURITIUS","Port Louis"}, {"MOROCCO","Rabat"},

{"MOZAMBIQUE","Maputo"}, {"NAMIBIA","Windhoek"},

{"NIGER","Niamey"}, {"NIGERIA","Abuja"},

{"RWANDA","Kigali"},

{"SAO TOME E PRINCIPE","Sao Tome"},

{"SENEGAL","Dakar"}, {"SEYCHELLES","Victoria"},

{"SIERRA LEONE","Freetown"}, {"SOMALIA","Mogadishu"},

{"SOUTH AFRICA","Pretoria/Cape Town"},

{"SUDAN","Khartoum"},

{"SWAZILAND","Mbabane"}, {"TANZANIA","Dodoma"},

{"TOGO","Lome"}, {"TUNISIA","Tunis"},

{"UGANDA","Kampala"},

{"DEMOCRATIC REPUBLIC OF THE CONGO (ZAIRE)",

"Kinshasa"},

{"ZAMBIA","Lusaka"}, {"ZIMBABWE","Harare"},

// Asia

{"AFGHANISTAN","Kabul"}, {"BAHRAIN","Manama"},

{"BANGLADESH","Dhaka"}, {"BHUTAN","Thimphu"},

{"BRUNEI","Bandar Seri Begawan"},

{"CAMBODIA","Phnom Penh"},

{"CHINA","Beijing"}, {"CYPRUS","Nicosia"},

{"INDIA","New Delhi"}, {"INDONESIA","Jakarta"},

{"IRAN","Tehran"}, {"IRAQ","Baghdad"},

{"ISRAEL","Jerusalem"}, {"JAPAN","Tokyo"},

{"JORDAN","Amman"}, {"KUWAIT","Kuwait City"},

{"LAOS","Vientiane"}, {"LEBANON","Beirut"},

{"MALAYSIA","Kuala Lumpur"}, {"THE MALDIVES","Male"},

{"MONGOLIA","Ulan Bator"},

{"MYANMAR (BURMA)","Rangoon"},

{"NEPAL","Katmandu"}, {"NORTH KOREA","P'yongyang"},

{"OMAN","Muscat"}, {"PAKISTAN","Islamabad"},

{"PHILIPPINES","Manila"}, {"QATAR","Doha"},

{"SAUDI ARABIA","Riyadh"}, {"SINGAPORE","Singapore"},

{"SOUTH KOREA","Seoul"}, {"SRI LANKA","Colombo"},

{"SYRIA","Damascus"},

{"TAIWAN (REPUBLIC OF CHINA)","Taipei"},

{"THAILAND","Bangkok"}, {"TURKEY","Ankara"},

{"UNITED ARAB EMIRATES","Abu Dhabi"},

{"VIETNAM","Hanoi"}, {"YEMEN","Sana'a"},

// Australia and Oceania

{"AUSTRALIA","Canberra"}, {"FIJI","Suva"},

{"KIRIBATI","Bairiki"},

{"MARSHALL ISLANDS","Dalap-Uliga-Darrit"},

{"MICRONESIA","Palikir"}, {"NAURU","Yaren"},

{"NEW ZEALAND","Wellington"}, {"PALAU","Koror"},

{"PAPUA NEW GUINEA","Port Moresby"},

{"SOLOMON ISLANDS","Honaira"}, {"TONGA","Nuku'alofa"},

{"TUVALU","Fongafale"}, {"VANUATU","< Port-Vila"},

{"WESTERN SAMOA","Apia"},

// Eastern Europe and former USSR

{"ARMENIA","Yerevan"}, {"AZERBAIJAN","Baku"},

{"BELARUS (BYELORUSSIA)","Minsk"},

{"BULGARIA","Sofia"}, {"GEORGIA","Tbilisi"},

{"KAZAKSTAN","Almaty"}, {"KYRGYZSTAN","Alma-Ata"},

{"MOLDOVA","Chisinau"}, {"RUSSIA","Moscow"},

{"TAJIKISTAN","Dushanbe"},

{"TURKMENISTAN","Ashkabad"},

{"UKRAINE","Kyiv"}, {"UZBEKISTAN","Tashkent"},

// Europe

{"ALBANIA","Tirana"}, {"ANDORRA","Andorra la Vella"},

{"AUSTRIA","Vienna"}, {"BELGIUM","Brussels"},

{"BOSNIA","---"}, {"HERZEGOVINA","Sarajevo"},

{"CROATIA","Zagreb"}, {"CZECH REPUBLIC","Prague"},

{"DENMARK","Copenhagen"}, {"ESTONIA","Tallinn"},

{"FINLAND","Helsinki"}, {"FRANCE","Paris"},

{"GERMANY","Berlin"}, {"GREECE","Athens"},

{"HUNGARY","Budapest"}, {"ICELAND","Reykjavik"},

{"IRELAND","Dublin"}, {"ITALY","Rome"},

{"LATVIA","Riga"}, {"LIECHTENSTEIN","Vaduz"},

{"LITHUANIA","Vilnius"}, {"LUXEMBOURG","Luxembourg"},

{"MACEDONIA","Skopje"}, {"MALTA","Valletta"},

{"MONACO","Monaco"}, {"MONTENEGRO","Podgorica"},

{"THE NETHERLANDS","Amsterdam"}, {"NORWAY","Oslo"},

{"POLAND","Warsaw"}, {"PORTUGAL","Lisbon"},

{"ROMANIA","Bucharest"}, {"SAN MARINO","San Marino"},

{"SERBIA","Belgrade"}, {"SLOVAKIA","Bratislava"},

{"SLOVENIA","Ljuijana"}, {"SPAIN","Madrid"},

{"SWEDEN","Stockholm"}, {"SWITZERLAND","Berne"},

{"UNITED KINGDOM","London"}, {"VATICAN CITY","---"},

// North and Central America

{"ANTIGUA AND BARBUDA","Saint John's"},

{"BAHAMAS","Nassau"},

{"BARBADOS","Bridgetown"}, {"BELIZE","Belmopan"},

{"CANADA","Ottawa"}, {"COSTA RICA","San Jose"},

{"CUBA","Havana"}, {"DOMINICA","Roseau"},

{"DOMINICAN REPUBLIC","Santo Domingo"},

{"EL SALVADOR","San Salvador"},

{"GRENADA","Saint George's"},

{"GUATEMALA","Guatemala City"},

{"HAITI","Port-au-Prince"},

{"HONDURAS","Tegucigalpa"}, {"JAMAICA","Kingston"},

{"MEXICO","Mexico City"}, {"NICARAGUA","Managua"},

{"PANAMA","Panama City"}, {"ST. KITTS","---"},

{"NEVIS","Basseterre"}, {"ST. LUCIA","Castries"},

{"ST. VINCENT AND THE GRENADINES","Kingstown"},

{"UNITED STATES OF AMERICA","Washington, D.C."},

// South America

{"ARGENTINA","Buenos Aires"},

{"BOLIVIA","Sucre (legal)/La Paz(administrative)"},

{"BRAZIL","Brasilia"}, {"CHILE","Santiago"},

{"COLOMBIA","Bogota"}, {"ECUADOR","Quito"},

{"GUYANA","Georgetown"}, {"PARAGUAY","Asuncion"},

{"PERU","Lima"}, {"SURINAME","Paramaribo"},

{"TRINIDAD AND TOBAGO","Port of Spain"},

{"URUGUAY","Montevideo"}, {"VENEZUELA","Caracas"},

};

// Use AbstractMap by implementing entrySet()

private static class FlyweightMap

extends AbstractMap<String,String> {

private static class Entry

implements Map.Entry<String,String> {

int index;

Entry(int index) { this.index = index; }

@Override

public boolean equals(Object o) {

return DATA[index][0].equals(o);

}

@Override

public String getKey() { return DATA[index][0]; }

@Override

public String getValue() { return DATA[index][1]; }

@Override

public String setValue(String value) {

throw new UnsupportedOperationException();

}

@Override

public int hashCode() {

return DATA[index][0].hashCode();

}

}

// Implement size() & iterator() for AbstractSet:

static class EntrySet

extends AbstractSet<Map.Entry<String,String>> {

private int size;

EntrySet(int size) {

if(size < 0)

this.size = 0;

// Can't be any bigger than the array:

else if(size > DATA.length)

this.size = DATA.length;

else

this.size = size;

}

@Override

public int size() { return size; }

private class Iter

implements Iterator<Map.Entry<String,String>> {

// Only one Entry object per Iterator:

private Entry entry = new Entry(-1);

@Override

public boolean hasNext() {

return entry.index < size - 1;

}

@Override

public Map.Entry<String,String> next() {

entry.index++;

return entry;

}

@Override

public void remove() {

throw new UnsupportedOperationException();

}

}

@Override

public

Iterator<Map.Entry<String,String>> iterator() {

return new Iter();

}

}

private static Set<Map.Entry<String,String>> entries =

new EntrySet(DATA.length);

@Override

public Set<Map.Entry<String,String>> entrySet() {

return entries;

}

}

// Create a partial map of 'size' countries:

static Map<String,String> select(final int size) {

return new FlyweightMap() {

@Override

public Set<Map.Entry<String,String>> entrySet() {

return new EntrySet(size);

}

};

}

static Map<String,String> map = new FlyweightMap();

public static Map<String,String> capitals() {

return map; // The entire map

}

public static Map<String,String> capitals(int size) {

return select(size); // A partial map

}

static List<String> names =

new ArrayList<>(map.keySet());

// All the names:

public static List<String> names() { return names; }

// A partial list:

public static List<String> names(int size) {

return new ArrayList<>(select(size).keySet());

}

public static void main(String[] args) {

System.out.println(capitals(10));

System.out.println(names(10));

System.out.println(new HashMap<>(capitals(3)));

System.out.println(new LinkedHashMap<>(capitals(3)));

System.out.println(new TreeMap<>(capitals(3)));

System.out.println(new Hashtable<>(capitals(3)));

System.out.println(new HashSet<>(names(6)));

System.out.println(new LinkedHashSet<>(names(6)));

System.out.println(new TreeSet<>(names(6)));

System.out.println(new ArrayList<>(names(6)));

System.out.println(new LinkedList<>(names(6)));

System.out.println(capitals().get("BRAZIL"));

}

}

/* Output:

{ALGERIA=Algiers, ANGOLA=Luanda, BENIN=Porto-Novo,

BOTSWANA=Gaberone, BURKINA FASO=Ouagadougou,

BURUNDI=Bujumbura, CAMEROON=Yaounde, CAPE VERDE=Praia,

CENTRAL AFRICAN REPUBLIC=Bangui, CHAD=N'djamena}

[ALGERIA, ANGOLA, BENIN, BOTSWANA, BURKINA FASO, BURUNDI,

CAMEROON, CAPE VERDE, CENTRAL AFRICAN REPUBLIC, CHAD]

{BENIN=Porto-Novo, ANGOLA=Luanda, ALGERIA=Algiers}

{ALGERIA=Algiers, ANGOLA=Luanda, BENIN=Porto-Novo}

{ALGERIA=Algiers, ANGOLA=Luanda, BENIN=Porto-Novo}

{ALGERIA=Algiers, ANGOLA=Luanda, BENIN=Porto-Novo}

[BENIN, BOTSWANA, ANGOLA, BURKINA FASO, ALGERIA, BURUNDI]

[ALGERIA, ANGOLA, BENIN, BOTSWANA, BURKINA FASO, BURUNDI]

[ALGERIA, ANGOLA, BENIN, BOTSWANA, BURKINA FASO, BURUNDI]

[ALGERIA, ANGOLA, BENIN, BOTSWANA, BURKINA FASO, BURUNDI]

[ALGERIA, ANGOLA, BENIN, BOTSWANA, BURKINA FASO, BURUNDI]

Brasilia

*/