從不耐煩的Core Java中：變量只能保存對對象的引用...我像這樣嘗試，它似乎可以工作：public class Person{    public String m_name;    public int m_age;    Person (final String name, final int age){        m_name = name;        m_age = age;    }    public static void main(String[] args){        Person a = new Person("John", 45);        Person b = a;        System.out.printf("Person a is %s, aged %d\n", a.m_name, a.m_age);        System.out.printf("Person b is %s, aged %d\n", b.m_name, b.m_age);        a.m_name = "Bob";        System.out.printf("Person a is now %s, aged %d\n", a.m_name, a.m_age);        System.out.printf("Person b is now %s, aged %d\n", b.m_name, b.m_age);    }}/*Output:Person a is John, aged 45Person b is John, aged 45Person a is now Bob, aged 45Person b is now Bob, aged 45*/但是，它似乎不僅僅適用于String對象或基本類型（盡管，從類實例的意義上講，后者并不是對象）：String aS = "John";String bS = aS;aS = "Bob";System.out.println(aS + '\n' + bS);/*Output:BobJohn*/int a = 10;int b = a; a = 5; System.out.printf("a = %d, b = %d", a, b);/*Output:a = 5, b = 10*/我想知道為什么要這樣二分法嗎？謝謝ps：Person類的屬性是公共的，以避免此簡單示例的更改器，訪問器