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    Java中的Java.util.EnumMap.entrySet()方法用于创建EnumMap中包含的元素集。它基本上返回枚举映射的设置视图。

    句法:

    enum_map.entrySet()

    参数:该方法不带任何参数。

    返回值:该方法返回此enum_map中包含的映射的set视图。

    下面的程序说明了Java.util.EnumMap.entrySet()方法

    程序1:

    // Java program to demonsrate entrySet() method
    import java.util.*;
    
    // An enum of gfg rank is created
    public enum rank_countries {
        India,
        United_States,
        China,
        Japan,
        Canada,
        Russia
    }
    ;
    
    class Enum_map {
        public static void main(String[] args)
        {
    
            EnumMap<rank_countries, Integer> mp = new
            EnumMap<rank_countries, Integer>(rank_countries.class);
    
            // Values are associated in mp
            mp.put(rank_countries.India, 72);
            mp.put(rank_countries.United_States, 1083);
            mp.put(rank_countries.China, 4632);
            mp.put(rank_countries.Japan, 6797);
    
            // Map view
            System.out.println("Map view: " + mp);
    
            // Creating a new set of the mappings
            // contained in map
            Set<Map.Entry<rank_countries, Integer> > set_view =
                                                    mp.entrySet();
    
            // Set view of the mappings
            System.out.println("Set view of the map: " + set_view);
        }
    }
    

    输出:

    Map view: {India=72, United_States=1083, China=4632, Japan=6797}
    Set view of the map: [India=72, United_States=1083, China=4632, Japan=6797]

    程序2:

    // Java program to demonsrate entrySet() method
    import java.util.*;
    
    // An enum of gfg ranking worldwide and in india
    public enum gfg {
        Global_2018,
        India_2018
    };
    
    class Enum_map {
        public static void main(String[] args)
        {
    
            EnumMap<gfg, Integer> mp = new
                  EnumMap<gfg, Integer>(gfg.class);
    
            // Values are associated in mp
            mp.put(gfg.Global_2018, 800);
            mp.put(gfg.India_2018, 72);
    
            // Mapping view
            System.out.println("Mapping view: " + mp);
    
            // Creating a new set of the mappings
            Set<Map.Entry<gfg, Integer> > set_view =
                                        mp.entrySet();
    
            // Set view of the mappings
            System.out.println("Set view of the map: "
                                          + set_view);
        }
    }
    

    输出:

    Mapping view: {Global_2018=800, India_2018=72}
    Set view of the map: [Global_2018=800, India_2018=72]

     
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