How do you use equals and hashCode with a simple code example?

In Java, the `equals()` method is used to compare two objects for equality. The `hashCode()` method is used in conjunction with `equals()` to provide a hash code value for the object. It is important to override both methods when creating a class so that it can be used correctly in collections such as HashMap or HashSet.

Here's a simple example demonstrating the usage of `equals()` and `hashCode()` in a custom Java class:


        public class Person {
            private String name;
            private int age;

            public Person(String name, int age) {
                this.name = name;
                this.age = age;
            }

            @Override
            public boolean equals(Object obj) {
                if (this == obj) return true;
                if (obj == null || getClass() != obj.getClass()) return false;
                Person person = (Person) obj;
                return age == person.age && name.equals(person.name);
            }

            @Override
            public int hashCode() {
                return Objects.hash(name, age);
            }

            // Getters and Setters
        }

        public static void main(String[] args) {
            Person person1 = new Person("John", 30);
            Person person2 = new Person("John", 30);

            System.out.println(person1.equals(person2)); // true
            System.out.println(person1.hashCode() == person2.hashCode()); // true
        }

How do you use equals and hashCode with a simple code example?

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How do you use equals and hashCode with a simple code example?

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