Java引用数据类型

class Person {
    int age;
    String name;

    public Person() {
    }

    public Person(int age, String name) {
        this.age = age;
        this.name = name;
    }

    @Override
    public String toString() {
        return "Person{" +
                "age=" + age +
                ", name='" + name + '\'' +
                '}';
    }


    public static void main(String[] args) {
        List<Person> personList = new ArrayList<>();
        Person person = new Person(12, "jack");
        Person person1 = new Person(121, "jack1");
        Person person2 = new Person(122, "jack2");
        Person person3 = new Person(123, "jack3");

        personList.add(person);
        personList.add(person1);
        personList.add(person2);
        personList.add(person3);

        System.out.println(personList);

        Person person4 = personList.get(0);
        person4.name = "newName";

        System.out.println(personList);

    }
}

输出结果：

[Person{age=12, name=‘jack’}, Person{age=121, name=‘jack1’}, Person{age=122, name=‘jack2’}, Person{age=123, name=‘jack3’}]

[Person{age=12, name=‘newName’}, Person{age=121, name=‘jack1’}, Person{age=122, name=‘jack2’}, Person{age=123, name=‘jack3’}]