El método Java.util.EnumMap.keySet() en Java se usa para devolver la vista establecida de las claves contenidas en el mapa.
Sintaxis:
Enum_Map.keySet()
Parámetros: El método no acepta ningún argumento.
Valor devuelto: el método devuelve la vista establecida de las claves contenidas en el mapa.
Los siguientes programas ilustran la función keySet():
Programa 1:
// Java program to demonstrate keySet()
import java.util.*;
// An enum of geeksforgeeks
public enum gfg {
India,
United_States,
China
};
class Enum_demo {
public static void main(String[] args)
{
EnumMap<gfg, String> mp = new
EnumMap<gfg, String>(gfg.class);
// Values are associated
mp.put(gfg.India, "61.7%");
mp.put(gfg.United_States, "18.2%");
mp.put(gfg.China, "2.5%");
// Prints the map
System.out.println("Mappings: " + mp);
// Store the set view of the key
Set<gfg> set_view = mp.keySet();
// Print the result
System.out.println("Set view of the key: " +
set_view);
}
}
Producción:
Mappings: {India=61.7%, United_States=18.2%, China=2.5%}
Set view of the key: [India, United_States, China]
Programa 2:
// Java program to demonstrate keySet()
import java.util.*;
// An enum of geeksforgeeks
public enum gfg {
Global_today,
India_today
};
class Enum_demo {
public static void main(String[] args)
{
EnumMap<gfg, Integer> mp =
new EnumMap<gfg, Integer>(gfg.class);
// Values are associated
mp.put(gfg.Global_today, 799);
mp.put(gfg.India_today, 69);
// Prints the map
System.out.println("Mappings: " + mp);
// Store the set view of the key
Set<gfg> set_view = mp.keySet();
// Print the result
System.out.println("Set view of the key: " +
set_view);
}
}
Producción:
Mappings: {Global_today=799, India_today=69}
Set view of the key: [Global_today, India_today]