Enum is only an information sort and it comprises of gathering of constants and in the meantime enum can be utilized for headings and weeks, for example, SUNDAY, MONDAY, WEDNESDAY, and so forth. An Enum has been presented from JDK 1.5 rendition. Enum guide is a guide usage for the enum. Taking after is the syntax of the java.util EnumMap Class. [java] public class EnumMap<K extends Enum<K>,V> extends AbstractMap<K,V> implements Serializable, Cloneable [/java] Where the Serializable and Cloneable are the interfaces that needs to be implemented.

Following are the common using methods of java.util EnumMap Class.

Following is the syntax declaration of the method. [java]public void clear()[/java] DemoEnumMap.java [java] package com.SPlessons; import java.util.*; public class DemoEnumMap { // create an enum public enum Numbers{ONE, TWO, THREE, FOUR, FIVE}; public static void main(String[] args) { EnumMap<Numbers,String> map = new EnumMap<Numbers,String>(Numbers.class); // associate values in map map.put(Numbers.ONE, "1"); map.put(Numbers.TWO, "2"); map.put(Numbers.THREE,"3"); map.put(Numbers.FOUR, "4"); // print the whole map System.out.println(map); // clear the mappings map.clear(); // print the map again System.out.println(map); } } [/java] Now understand the code without using clear() method. Following is the result. [java] {ONE=1, TWO=2, THREE=3, FOUR=4} {ONE=1, TWO=2, THREE=3, FOUR=4} [/java] Output: Now compile the code result will be as follows. [java] {ONE=1, TWO=2, THREE=3, FOUR=4} {} [/java]

Following is the syntax declaration of the method. [java]public boolean containsKey(Object key)[/java] DemoEnum.java [java] package com.SPlessons; import java.util.*; public class DemoEnumMap { // create an enum public enum Numbers{ONE, TWO, THREE, FOUR, FIVE}; public static void main(String[] args) { EnumMap<Numbers,String> map = new EnumMap<Numbers,String>(Numbers.class); // associate values in map map.put(Numbers.ONE, "1"); map.put(Numbers.TWO, "2"); map.put(Numbers.THREE,"3"); map.put(Numbers.FOUR, "4"); // print the whole map System.out.println(map); // check if map contains a mapping at specified key boolean contains = map.containsKey(Numbers.ONE); // print the result System.out.println("Numbers.ONE has a mapping:" + contains); // check if map contains a mapping at another specified key contains = map.containsKey(Numbers.FIVE); // print the result System.out.println("Numbers.FIVE has a mapping:" + contains); } } [/java] In the above example, while mapping the keys with values FIVE was not used so it returns false. Output: Now compile the code result will be as follows. [java] {ONE=1, TWO=2, THREE=3, FOUR=4} Numbers.ONE has a mapping:true Numbers.FIVE has a mapping:false [/java]

Following is the syntax declaration of the method. [java]public boolean containsValue(Object value)[/java] DemoEnum.java [java] package com.SPlessons; import java.util.*; public class DemoEnumMap { // create an enum public enum Numbers{ONE, TWO, THREE, FOUR, FIVE}; public static void main(String[] args) { EnumMap<Numbers,String> map = new EnumMap<Numbers,String>(Numbers.class); // associate values in map map.put(Numbers.ONE, "1"); map.put(Numbers.TWO, "2"); map.put(Numbers.THREE,"3"); map.put(Numbers.FOUR, "4"); // print the whole map System.out.println(map); // check if map contains a mapping for specified key boolean contains = map.containsValue("1"); // print the result System.out.println("Map contains '1':" + contains); // check if map contains a mapping at another specified key contains = map.containsValue("5"); // print the result System.out.println("Map contains '5':" + contains); } } [/java] In the above example, values of the code will be returned, where the value 5 has not been mentioned so it returns false. Output: Now compile the code result will be as follows. [java] {ONE=1, TWO=2, THREE=3, FOUR=4} Map contains '1':true Map contains '5':false [/java]

Following is the syntax declaration of the method. [java]public V get(Object key)[/java] DemoEnum.java [java] package com.SPlessons; import java.util.*; public class DemoEnumMap { // create an enum public enum Numbers { ONE, TWO, THREE, FOUR, FIVE }; public static void main(String[] args) { EnumMap<Numbers, String> map = new EnumMap<Numbers, String>(Numbers.class); // associate values in map1 map.put(Numbers.ONE, "1"); map.put(Numbers.TWO, "2"); map.put(Numbers.THREE, "3"); map.put(Numbers.FOUR, "4"); // print the map System.out.println(map); // get the value for Numbers.ONE String value = map.get(Numbers.ONE); // print the result System.out.println("Numbers.ONE value:" + value); System.out.println("Numbers.FIVE value:" + map.get(Numbers.FIVE)); System.out.println("Numbers.FOUR value:" + map.get(Numbers.FOUR)); } } [/java] In above example, The developer used get() method, where FIVE does not have any value so it returns false in the result. Output: Now compile the code result will be as follows. [java] {ONE=1, TWO=2, THREE=3, FOUR=4} Numbers.ONE value:1 Numbers.FIVE value:null Numbers.FOUR value:4 [/java]

Following is the syntax declaration of the method. [java]public Collection<V> values()[/java] DemoEnum.java [java] package com.SPlessons; import java.util.*; public class DemoEnumMap { // create an enum public enum Numbers { ONE, TWO, THREE, FOUR, FIVE }; public static void main(String[] args) { EnumMap<Numbers, String> map = new EnumMap<Numbers, String>(Numbers.class); // assosiate values in map map.put(Numbers.ONE, "1"); map.put(Numbers.TWO, "2"); map.put(Numbers.THREE, "3"); map.put(Numbers.FOUR, "4"); map.put(Numbers.FIVE, "5"); // print the map System.out.println("Map: " + map); // create a new collection and create the view Collection<String> values = map.values(); // print the collection view System.out.println("Collection:" + values); } } [/java] In the above example, the developer used five values and 5 keys so the total collection will be printed in the result. Output: Now compile the code result will be as follows. [java] Map: {ONE=1, TWO=2, THREE=3, FOUR=4, FIVE=5} Collection:[1, 2, 3, 4, 5] [/java]

• Java.util EnumMap - The java.util.EnumMap.size() method is used to return the size of the keys in map.
• Java.util EnumMap - The java.util.EnumMap.remove() method is used to remove the mapping in map.
• The java.util.EnumMap.put() method is used to return particular key with particular value.