Jan 8, 2024 · Simply put, hashCode () returns an integer value, generated by a hashing algorithm. Objects that are equal (according to their equals ()) must return the same hash code. Different objects do not need to return different hash codes. The general contract of hashCode () states:

Dec 3, 2024 · This method returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element. Example: [GFGTABS] Java // Java Program to Implement List // indexOf() Method import java.util.*; class GFG …

Feb 29, 2016 · The hashCode of ArrayList is a function of the hashCodes of all the elements stored in the ArrayList, so it doesn't change when the capacity changes, it changes whenever you add or remove an element or mutate one of the elements in a way that changes its hashCode.

How do we decide on the best implementation of hashCode() method for a collection (assuming that equals method has been overridden correctly) ? with Java 7+, I guess Objects.hashCode(collection) should be a perfect solution!

The List interface places additional stipulations, beyond those specified in the Collection interface, on the contracts of the iterator, add, remove, equals, and hashCode methods. Declarations for other inherited methods are also included here for convenience.

Jun 16, 2010 · The hash code of a list is defined to be the result of the following calculation: hashCode = 1; Iterator i = list.iterator(); while (i.hasNext()) { Object obj = i.next(); hashCode = 31*hashCode + (obj==null ? 0 : obj.hashCode()); }

Mar 24, 2025 · The hashCode() method of List interface returns the hash code value for this list. Syntax public int hashCode() Parameters NA Specified By hashcode in interf...

Jun 19, 2024 · Learn how Java hashcode calculations work, why they're important for collections like HashMap and HashSet, and best practices for implementing hashCode.

Jul 22, 2022 · Java List hashCode() Method with Examples on java, list, containsAll(), equals(), get(), hashCode(), indexOf(), isEmpty(), add(), contains(), size(), listIterator(), clear(), remove(), toArray(), retainAll(), removeAll() etc.

Nov 26, 2018 · The hashCode() method of java.util.AbstractList class is used to return the hash code value for this list. Syntax: public int hashCode() Returns Value: This method returns the hash code value for this list. Below are the examples to illustrate the hashCode() method. Example 1: