What is the importance of hashCode() and equals() methods ?

3 years ago
OOP Java

In Java, a HashMap uses the hashCode and equals methods to determine the index of the key-value pair and to detect duplicates. More specifically, the hashCode method is used in order to determine where the specified key will be stored. Since different keys may produce the same hash value, the equals method is used, in order to determine whether the specified key actually exists in the collection or not. Therefore, the implementation of both methods is crucial to the accuracy and efficiency of the HashMap.

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Surya Bikram Bhandari
Surya Bikram Bhandari
Oct 31, 2021
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