The Java.util.EnumMap.containsKey(key) method is used to check whether a specified key mentioned in the parameter is present in this map or not.
Syntax:
boolean containsKey(Object key)
Parameter: The method accepts one parameter key which refer to the key to be verified.
Return Value: The method returns true if the key is present in the EnumMap otherwise it returns false.
Below programs illustrate the containsKey() method:
Program 1:
// Java program to demonstrate containsKey() methodimport java.util.*; // An enum of gfg visitors is createdpublic enum gfg_visitors { India, United_States, China, Japan, Canada}; class Enum_map { public static void main(String[] args) { EnumMap<gfg_visitors, String> mp = new EnumMap<gfg_visitors, String>(gfg_visitors.class); // values are associated in mp mp.put(gfg_visitors.India, "61.4%"); mp.put(gfg_visitors.United_States, "18.4%"); mp.put(gfg_visitors.China, "2.5%"); mp.put(gfg_visitors.Japan, "1.1%"); mp.put(gfg_visitors.Canada, "1.1%"); // Check if map contains gfg visitor from United_States boolean ans = mp.containsKey(gfg_visitors.United_States); // Prints the result System.out.println("gfg_visitors from United States: " + ans); }} |
Output:
gfg_visitors from United States: true
Program 2:
// Java program to demonstrate containsKey() methodimport java.util.*; // An enum of gfg visitors is createdpublic enum gfg_visitors { India, United_States, China, Japan, Canada, Russia}; class Enum_map { public static void main(String[] args) { EnumMap<gfg_visitors, String> mp = new EnumMap<gfg_visitors, String>(gfg_visitors.class); // values are associated in mp mp.put(gfg_visitors.India, "61.4%"); mp.put(gfg_visitors.United_States, "18.4%"); mp.put(gfg_visitors.China, "2.5%"); mp.put(gfg_visitors.Japan, "1.1%"); mp.put(gfg_visitors.Canada, "1.1%"); // check if map contains gfg visitor from Russia boolean ans = mp.containsKey(gfg_visitors.Russia); // prints the result System.out.println("gfg_visitors from Russia: " + ans); }} |
Output:
gfg_visitors from Russia: false
