java enummap

EnumMap类的get()方法 (EnumMap Class get() method)

• get() method is available in java.util package.

  get()方法在java.util包中可用。

• get() method is used to get the value mapped with the given key element (key_ele) otherwise it returns null when no value associated with the given key element (key_ele).

  get()方法用于获取与给定键元素( key_ele )映射的值，否则，当没有与给定键元素( key_ele )相关联的值时，它返回null。

• get() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  get()方法是一个非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。

• get() method does not throw an exception at the time of returning element mapped to the given key.

  返回映射到给定键的元素时， get()方法不会引发异常。

Syntax:

句法：

public Value get(Object key_ele);

Parameter(s):

参数：

• Object key_ele – represents the key element of this enum map.

  object key_ele –表示此枚举映射的关键元素。

Return value:

返回值：

The return type of this method is Value, it returns the mapped value of the given key element (key_ele) when exists else it returns null.

此方法的返回类型为Value ，如果存在则返回给定键元素( key_ele )的映射值，否则返回null。

Example:

例：

// Java program to demonstrate the example // of Value get(Object key_ele) method of // EnumMapimport java.util.*;public class GetOfEnumMap {
       public enum Colors {
           RED,        BLUE,        PINK,        YELLOW    };    public static void main(String[] args) {
           // We are creating EnumMap object        EnumMap < Colors, String > em =            new EnumMap < Colors, String > (Colors.class);        // By using put() method is to        // add the linked values in an        // EnumMap (em)        em.put(Colors.RED, "1");        em.put(Colors.BLUE, "2");        em.put(Colors.PINK, "3");        em.put(Colors.YELLOW, "4");        // Display EnumMap        System.out.println("EnumMap (em) :" + em);        // By using get(key_ele) method isto        // return the value of the given key        // element (key_ele) when exists otherwise        // it returns null        String val_ele = em.get(Colors.BLUE);        // Display val_ele of the given key         // element in an EnumMap        System.out.println("em.get(Colors.BLUE): " + val_ele);    }}

Output

输出量

EnumMap (em) :{RED=1, BLUE=2, PINK=3, YELLOW=4}em.get(Colors.BLUE): 2

翻译自:

java enummap