java compare objects by value (equals method example)

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// Student.java file:

import java.util.Objects;

public static class Student {

    private int id;
    private String name;

    public Student(int id, String name) {
        this.id = id;
        this.name = name;
    }

    public int getId() {
        return this.id;
    }

    public String getName() {
        return this.name;
    }

    @Override
    public boolean equals(Object object) { // <----------- equals let's to compare objects by value
        if (object == null) return false;
        if (object == this) return true;   // if same references
        if (object instanceof Student) {
            Student student = (Student) object;
            return Objects.equals(this.id, student.id) && Objects.equals(this.name, student.name);
        }
        return false;
    }
}


// Program.java file:

public class Program {

    public static void main(String[] args) {

        Student a = new Student(1, "John");
        Student b = new Student(2, "Matt");
        Student c = new Student(2, "Matt");

        boolean result1 = a.equals(b);  // false
        boolean result2 = a.equals(c);  // false

        boolean result3 = b.equals(b);  // true
        boolean result4 = b.equals(c);  // true
    }
}