1. hashCode method Java is an object-oriented programming language. All classes inherit from the Object class by default. The Object class contains the hashCode() method. // Java 1.8 public native int hashCode(); // Java 9 @HotSpotIntrinsicCandidate public native int hashCode(); This means that all classes will have a hashCode() method, which returns a value of […]
Tag: hashcode
In-depth discussion of hashCode method in java
Overview Students who have studied Java should all know that when rewriting the equals method, we have to rewrite the hashCode method, so why do we do this and what is the significance of doing so? The author will write an article here Let’s have an in-depth discussion with you based on “Effective Java”. The […]
Solve the rewriting problem of equals() and hashcode() in one article
Table of Contents Part 1 What does equals() do? Part 2 What is the difference between equals() and ==? Part 3 The role of hashCode() Part 4 The relationship between hashCode() and equals() Part 5: Several classic interview questions Part 1 What does equals() do? The function of equals() is used to determine whether two […]
A brief analysis of what the Obiect class has–equals method, toString method, hashCode method
The Obiect class is a class provided by Java by default. Except for the Obiect class, all classes in Java have an inheritance relationship and inherit the Object class by default. That is, we can think of the Object class as our top-level parent class. For example, let’s give an example to prove that Object […]
== and equals and hashCode
== “==” is the operator If the comparison object is a basic data type, the comparison is whether the stored values are equal; If the comparison is a reference data type, the comparison is whether the address value of the pointed object is equal (whether it is the same object). public static void main(String[] args) […]
Popular explanation of the relationship and functions of equals and hashCode
Foreword Why do you have to override the hashCode method when overriding the equals method? This is a familiar and basic interview question. As working hours increase, many of the eight-part interview theories are gradually verified in work practice. But there are also some theories. After passing the interview stage, it seems that they will […]
Java hashCode method and equals method
Java’s hashCode method and equals method Brief description public native int hashCode() public boolean equals(Object obj) {<!– –> return (this == obj); } Feature description Returns the hash value of the object. This method is supported for use with hash tables, such as those provided by java.util.HashMap. The general convention of hashCode is as follows: […]
Why should we rewrite hashCode() after rewriting equals()?
Why should we rewrite hashCode() after rewriting equals() Article 9 in Effective Java stipulates that when overriding the equals() method, always override the hashCode() method. Why is this? Next we will introduce these two methods. The equals() method and the hashCode() method in Java are both methods in the Object class, and all classes in […]
Issues related to hashCode() and equals()
I have been vague about the issues related to hashCode() and equals before, and I think the answers to the questions are a bit irrelevant. Organize and summarize the problems of hashCod and equals:1. What is the function of equals()? The function of equals() is used to judge whether two objects are equal. equals() is […]
== operator, equals method and hashCode method in Java
1. == operator == is an operator in Java that is used to compare two objects, but when comparing two objects, it needs to be discussed according to the type of comparison. 1.1 Basic data types and basic data types When the basic data types are compared by ==, their sizes are compared directly, regardless […]