Equals() method here i dont get Object obj and this==obj. What is it plis help

Question

class Animal {
String name;
Animal(String n) {
name = n;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((name == null) ? 0 : name.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Animal other = (Animal) obj;
if (name == null) {
if (other.name != null)
return false;
} else if (!name.equals(other.name))
return false;
return true;
}
}

class Program {
public static void main(String[ ] args) {
Animal a1 = new Animal("Robby");
Animal a2 = new Animal("Robby");
System.out.println(a1.equals(a2));
}
}

Answer 1

In animal class constructor:
"this.name=n"
In equals method:
If(this.name==obj.name)
return true

Answer 2

Just edit them