The method is a java.util.Collections class method. It counts the frequency of the specified element in the given list. It override the equals() method to perform the comparison to check if the specified Object and the Object in the list are equal or not.
public static int frequency(Collection c, Object o) parameters: c: Collection in which to determine the frequency of o. o: Object whose frequency is to be determined. It throws Null Pointer Exception if the Collection c is null.
The frequency of the word code is: 3
Using Java.util. Collections.frequency() for Custom defined objects
The method stated above works well for already defined Objects in java, but what about the custom defined objects. Well, to count the frequency of a custom defined object in java, we will have to simply override the equals() method. Lets see how we can do that.
The frequency of the Student Ram,19 is: 2
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