Java EnumMap clone()用法及代碼示例

Java中的Java.util.EnumMap.clone()方法用於將一個映射的映射值複製到另一個。它本質上會創建此Map的淺拷貝。

用法:

Enum_map_2 = Enum_map_1.clone()

參數：該方法不接受任何參數。

返回值：該方法返回EnumMap的淺拷貝。

以下示例程序旨在說明Java.util.EnumMap.clone()方法

示例1:

// Java program to demonsrate clone() method 
import java.util.*; 
  
// An enum of fruits price is created 
public enum Price_of_Fruits { 
    Orange, 
    Apple, 
    Banana, 
    Pomegranate, 
    Guava 
}; 
  
class Enum_map { 
    public static void main(String[] args) 
    { 
  
        EnumMap<Price_of_Fruits, Integer> mp1 = new EnumMap<Price_of_Fruits, 
                                             Integer>(Price_of_Fruits.class); 
  
        EnumMap<Price_of_Fruits, Integer> mp2 = new EnumMap<Price_of_Fruits,  
                                             Integer>(Price_of_Fruits.class); 
  
        // Values are associated in mp1 
        mp1.put(Price_of_Fruits.Orange, 30); 
        mp1.put(Price_of_Fruits.Apple, 60); 
        mp1.put(Price_of_Fruits.Banana, 40); 
        mp1.put(Price_of_Fruits.Pomegranate, 120); 
        mp1.put(Price_of_Fruits.Guava, 20); 
  
        // Price of fruits in mp1 
        System.out.println("Price of fruits in 1st map " + mp1); 
  
        // Copying the values of mp1 to mp2 
        mp2 = mp1.clone(); 
  
        // Price of fruits in mp2 
        System.out.println("Price of fruits in 2nd map " + mp2); 
    } 
}

輸出：

Price of fruits in 1st map {Orange=30, Apple=60, Banana=40, Pomegranate=120, Guava=20}
Price of fruits in 2nd map {Orange=30, Apple=60, Banana=40, Pomegranate=120, Guava=20}

示例2:

// Java program to demonsrate clone() method 
import java.util.*; 
  
// An enum of gfg ranking is created 
public enum gfg_ranking { 
    Global_2018, 
    India_2018 
}; 
  
class Enum_map { 
    public static void main(String[] args) 
    { 
  
        EnumMap<gfg_ranking, Integer> mp1 = new EnumMap<gfg_ranking,  
                                          Integer>(gfg_ranking.class); 
  
        EnumMap<gfg_ranking, Integer> mp2 = new EnumMap<gfg_ranking, 
                                          Integer>(gfg_ranking.class); 
  
        // Values are associated in mp1 
        mp1.put(gfg_ranking.Global_2018, 800); 
        mp1.put(gfg_ranking.India_2018, 72); 
  
        // Price of fruits in mp1 
        System.out.println("GeeksforGeeks ranking in first map " + mp1); 
  
        // Copying the values of mp1 to mp2 
        mp2 = mp1.clone(); 
  
        // Price of fruits in mp2 
        System.out.println("GeeksforGeeks ranking in second map " + mp2); 
    } 
}

輸出：

GeeksforGeeks ranking in first map {Global_2018=800, India_2018=72}
GeeksforGeeks ranking in second map {Global_2018=800, India_2018=72}

相關用法

注：本文由純淨天空篩選整理自akash1295大神的英文原創作品 EnumMap clone() Method in Java。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。