Java EnumMap clear()用法及代码示例

Java中的Java.util.EnumMap.clear()方法用于从Map中删除所有映射。该方法不会删除Map，而是会清除映射的Map。

用法:

enum_map.clear()

参数：此方法不接受任何参数。

返回值：此方法不返回任何值。

以下程序说明了Java.util.EnumMap.clear()方法的用法：
示例1:

// Java program to demonstrate clear() method 
import java.util.*; 
  
// An enum of geeksforgeeks ranking across 
// Worldwide & in India is created 
public enum gfg { 
    Global, 
    India 
} 
; 
  
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, 800); 
        mp.put(gfg.India, 72); 
  
        // Values in mp before removing 
        System.out.println("Values in map before removing " + mp); 
  
        // Removing the values from mp 
        mp.clear(); 
  
        // Values in mp after removing 
        System.out.println("Values in map after removing " + mp); 
    } 
}

输出：

Values in map before removing {Global=800, India=72}
Values in map after removing {}

示例2:

// Java program to demonstrate clear() 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> mp = new EnumMap<Price_of_Fruits, Integer>(Price_of_Fruits.class); 
  
        // Values are associated in mp 
        mp.put(Price_of_Fruits.Orange, 30); 
        mp.put(Price_of_Fruits.Apple, 50); 
        mp.put(Price_of_Fruits.Banana, 40); 
        mp.put(Price_of_Fruits.Pomegranate, 120); 
        mp.put(Price_of_Fruits.Guava, 20); 
  
        // Values in mp before removing 
        System.out.println("Values in map before removing " + mp); 
  
        // Removing the values from mp 
        mp.clear(); 
  
        // Values in mp after removing 
        System.out.println("Values in map after removing " + mp); 
    } 
}

输出：

Values in map before removing {Orange=30, Apple=50, Banana=40, 
                                    Pomegranate=120, Guava=20}
Values in map after removing {}

相关用法

注：本文由纯净天空筛选整理自akash1295大神的英文原创作品 EnumMap clear() Method in Java with Examples。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。