Java对象深拷贝与浅拷贝区别及实现方法

class Address {
    String city;
    Address(String city) { this.city = city; }
}

class Person implements Cloneable {
    String name;
    Address addr;

    Person(String name, Address addr) {
        this.name = name;
        this.addr = addr;
    }

    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }
}

Address addr = new Address("Beijing");
Person p1 = new Person("Alice", addr);
Person p2 = (Person) p1.clone();

p2.addr.city = "Shanghai";

System.out.println(p1.addr.city); // 输出 Shanghai

public Object clone() throws CloneNotSupportedException {
    Person p = (Person) super.clone();
    p.addr = new Address(this.addr.city); // 手动克隆引用对象
    return p;
}

import java.io.*;

public class DeepCopyUtil {
    public static <T extends Serializable> T deepCopy(T obj) {
        try {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            ObjectOutputStream oos = new ObjectOutputStream(bos);
            oos.writeObject(obj);

            ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
            ObjectInputStream ois = new ObjectInputStream(bis);
            return (T) ois.readObject();
        } catch (Exception e) {
            throw new RuntimeException("深拷贝失败", e);
        }
    }
}