Question about getters and setters

Question

I want to ask you a bit simple question. I know, you can show me google but i know to understand this by my example. My program code:
class Readers {
     int age;
public Readers(){
     age = 45;
public int getAge() {
     return age;
public void setAge(int age) {
     this.age = age;
public void print_age(){
     System.out.println(+age);
class Main {
     public static void main(String[] Args) {
     Readers john = new Readers();
     john.print_age();
Why do i need use getters and setters? Because without these methods I get the same result. My program works correctly. Can you explain the benefit of using getters and setters?
Thanks in advance ;)

Answer 1

First, nobody said that you should use getters and setters in the first place. The only thing that's worse than dumb mutators/accessors would be the exposure of the attribute itself.
Second, you certainly don't need mutators "internally".
Third: consider you redesigning your class to store a person's birthdate instead of its age - makes sense if one thinks about it, doesn't it? If you have coded your entire program to access the "age" attribute of the object, you know have a problem because it was replaced by "birthday". The getter at least could calculate the current age from the birthdate - so no rewriting of the rest of your program would be necessary, just a small change in your getter.