如何在Java中扩展不可变类型

public final class ImmutablePerson {
    private final String name;
    private final int age;

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

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null || getClass() != obj.getClass()) {
            return false;
        }
        ImmutablePerson other = (ImmutablePerson) obj;
        return Objects.equals(name, other.name) && age == other.age;
    }

    @Override
    public int hashCode() {
        return Objects.hash(name, age);
    }

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