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This article mainly explains "how to use hashCode () in java". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Let's let the editor learn how to use hashCode () in java.

1. The function of hashCode is to get hash codes, also known as hash codes, which actually return int integers. The purpose of the hash code is to determine the index position of the object in the hash table.

2. HashCode is defined in the Object class of JDK, which means that any class in Java contains hashCode functions.

Example

Package com.tools; import java.util.ArrayList; public class HashCodeMeaning {public static void main (String [] args) {ArrayList list = new ArrayList (); int numberExist=0; / / proves that the value of hashcode is not the memory address for (int I = 0; I < 10000; iTunes +) {Object obj=new Object () If (list.contains (obj.toString () {System.out.println (obj.toString ()) + "exists in the list. "+ I); numberExist++;} else {list.add (obj.toString ());}} System.out.println (" repetition number: "+ numberExist); System.out.println (" list size: "+ list.size ()); / / prove that the memory address is different. NumberExist=0; list.clear (); for (int I = 0; I < 10000; iTunes +) {Object obj=new Object (); if (list.contains (obj)) {System.out.println (obj + "exists in the list. "+ I); numberExist++;} else {list.add (obj);}} System.out.println (" repetition number: "+ numberExist); System.out.println (" list size: "+ list.size ()) }} at this point, I believe you have a deeper understanding of "how to use hashCode () in java". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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