浅谈Java中实现深拷贝的两种方式—clone() & Serialized

clone() 方法麻烦一些，需要将所有涉及到的类实现声明式接口 Cloneable，并覆盖Object类中的clone()方法，并设置作用域为public（这是为了其他类可以使用到该clone方法）。

序列化的方法简单，需要将所有涉及到的类实现接口Serializable

package b1ch06.clone;

import java.io.Serializable;

class Car implements Cloneable, Serializable {
 private String band;

public Car(String band) {
   this.band = band;
 }

public String getBand() {
   return band;
 }

public void setBand(String band) {
   this.band = band;
 }

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

package b1ch06.clone;

import java.io.Serializable;

class Employee implements Cloneable, Serializable {
 private String name;
 private Car car;

public Employee(String name, Car car) {
   this.name = name;
   this.car = car;
 }

public String getName() {
   return name;
 }

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

public Car getcar() {
   return car;
 }

public void setcar(Car car) {
   this.car = car;
 }

protected void test() {
   System.out.println("test func");
 }

@Override
 public Object clone() throws CloneNotSupportedException {

Employee employee_cloned = (Employee) super.clone();
   Car car_cloned = (Car) this.car.clone();
   employee_cloned.setcar(car_cloned);
   return employee_cloned;
 }
}

package b1ch06.clone;

import java.io.*;

public class SerializedClone {
 @SuppressWarnings("unchecked")
 public static <T extends Serializable> T clone(T obj) {
   T cloneObj = null;
   try {
     //写入字节流
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     ObjectOutputStream obs = new ObjectOutputStream(out);
     obs.writeObject(obj);
     obs.close();

//分配内存，写入原始对象，生成新对象
     ByteArrayInputStream ios = new ByteArrayInputStream(out.toByteArray());
     ObjectInputStream ois = new ObjectInputStream(ios);
     //返回生成的新对象
     cloneObj = (T) ois.readObject();
     ois.close();
   } catch (Exception e) {
     e.printStackTrace();
   }
   return cloneObj;
 }

}

package b1ch06.clone;

public class MyClone {

public static void main(String[] args) {
   Car car = new Car("BMW");
   Employee employee = new Employee("ANDY", car);
   // 方法一：覆盖所有涉及到的类的clone()方法
   try {

Employee employee_cp = (Employee) employee.clone();

System.out.println("=========================");
     System.out.println("original对象地址?:");
     System.out.println(employee.toString());
     System.out.println("copy对象地址?:");
     System.out.println(employee_cp.toString());
     System.out.println("前后两个对象指向同一地址?:");
     System.out.println(employee_cp == employee);
     System.out.println("=========================");

System.out.println("original对象中car对象地址?:");
     System.out.println(employee.getcar().toString());
     System.out.println("copy对象中car对象地址?:");
     System.out.println(employee_cp.getcar().toString());
     System.out.println("前后两个car对象指向同一地址?:");
     System.out.println(employee_cp == employee);

} catch (CloneNotSupportedException e) {
     e.printStackTrace();
   }

// 方法二：序列化实现深拷贝
   Employee cloned_employee = SerializedClone.clone(employee);
   System.out.println("=========================");
   System.out.println("original对象地址?:");
   System.out.println(employee.toString());
   System.out.println("copy对象地址?:");
   System.out.println(cloned_employee.toString());
   System.out.println("前后两个对象指向同一地址?:");
   System.out.println(cloned_employee == employee);

System.out.println("=========================");

System.out.println("original对象中car对象地址?:");
   System.out.println(employee.getcar().toString());
   System.out.println("copy对象中car对象地址?:");
   System.out.println(cloned_employee.getcar().toString());
   System.out.println("前后两个car对象指向同一地址?:");
   System.out.println(cloned_employee == employee);

}
}

以上所述是小编给大家介绍的Java中实现深拷贝的两种方式--——clone() & Serialized详解整合网站的支持！

来源：https://blog.csdn.net/qq_37174526/article/details/86484517