JavaPassByValue.java

/**
    JAVA arguments are always pass by value (that means a copy of it)- either the arg is primitive value or an object’s reference like “object@1f89ab83” in the heap memory.
    Therefore we can change the state of the object passed but not its reference, and if we create another reference with the keyboard “new”.
**/

public class JavaPassByValue{
    public static void main(String[] args) {

        Person person = new Person("Donatelo");
        Person person2 = new Person("Leo");

        changeNameInstance(person);
        System.out.println(person.getName()); //prints Donatelo because the reference wasn't modified
        
        changeNameSetter(person2);
        System.out.println(person2.getName()); //prints Raph
    }

                                         //receives the copy of the reference Person@1f89ab83
    public static void changeNameInstance(Person person) {
        person = new Person("Mike"); //creates another reference Person@4d90a
        System.out.println(person.getName()); //prints Mike
    }

                                        //receives the copy of the reference 
    public static void changeNameSetter(Person person) {
        //changes the state of the object referenced 
        person.setName("Raph");
    }
}


class Person{
    private String name;

    public Person(String name){
        this.name = name;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        this.name = name;
    }
}

//javac JavaPassByValue.java
//java JavaPassByValue

//discussion https://stackoverflow.com/questions/40480/is-java-pass-by-reference-or-pass-by-value