java深拷贝和浅拷贝介绍

@Data
@Slf4j
public class Sheep implements Cloneable {
 private String name;
 private int age;
 private String color;
 private Sheep friend;

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

 @Override
 protected Object clone(){
 Sheep sheep = null;
 try {
 sheep = (Sheep) super.clone();
 } catch (Exception e) {
 log.info("" + e);
 }
 return sheep;
 }
}

@Data
public class DeepPrptoType implements Serializable, Cloneable {
 private static final long serialVersionUID = 1L;
 private String name;
 private DeepCloneableTarget deepCloneableTarget;

 public DeepPrptoType() {
 }

 //深拷贝方式1 使用clone方法
 @Override
 protected Object clone() throws CloneNotSupportedException {
 Object deep = null;
 //这里对基本数据类型和String对克隆
 deep = super.clone();
 DeepPrptoType deepPrptoType = (DeepPrptoType) deep;
 deepPrptoType.deepCloneableTarget = (DeepCloneableTarget) deepCloneableTarget.clone();
 return deepPrptoType;
 }

 //深拷贝，方式2 通过对象的序列化实现（推荐使用）
 public static <T extends Serializable> T deepClone(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;
 }
}

public class Client2 {
 public static void main(String[] args) throws CloneNotSupportedException {
 DeepPrptoType p = new DeepPrptoType();
 p.setName("深拷贝");
 p.setDeepCloneableTarget(new DeepCloneableTarget("大牛", "哈哈"));

 //方式一：深拷贝
 DeepPrptoType p2 = (DeepPrptoType) p.clone();
 System.out.println(p.getName() + p.getDeepCloneableTarget().hashCode());
 System.out.println(p2.getName() + p2.getDeepCloneableTarget().hashCode());

 //通过序列化和反序列化实现深拷贝，说明引用类型所指向的对象也被clone了
 DeepPrptoType p3 = DeepPrptoType.deepClone(p);
 System.out.println(p3.getName() + p3.getDeepCloneableTarget().hashCode());
 }
}