Java EnumMap - containsKey() Method
The java.util.EnumMap.containsKey() method returns true if this map contains a mapping for the specified key.
Syntax
public boolean containsKey(Object key)
Parameters
key |
Specify the key whose presence in this map is to be tested. |
Return Value
Returns true if this map contains a mapping for the specified key.
Exception
NA.
Example:
In the example below, the java.util.EnumMap.containsKey() method is used to check the presence of specified key in the given EnumMap.
import java.util.*;
public class MyClass {
//creating an enum
public enum weekday{
SUN, MON, TUE, WED, THU, FRI, SAT
}
public static void main(String[] args) {
//creating an EnumMap
EnumMap<weekday,Integer> MyMap =
new EnumMap<weekday,Integer>(weekday.class);
//associate values in the map
MyMap.put(weekday.MON, 1);
MyMap.put(weekday.TUE, 2);
MyMap.put(weekday.WED, 3);
MyMap.put(weekday.THU, 4);
MyMap.put(weekday.FRI, 5);
//printing EnumMap
System.out.println("MyMap contains: " + MyMap);
//check the presence of SUN key
System.out.print("Does MyMap contain SUN key? - ");
System.out.println(MyMap.containsKey(weekday.SUN));
//check the presence of FRI key
System.out.print("Does MyMap contain FRI key? - ");
System.out.println(MyMap.containsKey(weekday.FRI));
}
}
The output of the above code will be:
MyMap contains: {MON=1, TUE=2, WED=3, THU=4, FRI=5}
Does MyMap contain SUN key? - false
Does MyMap contain FRI key? - true
❮ Java.util - EnumMap
