public class Prototype{
 private String name;

 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 } 
 
}
public class NewPrototype implements Cloneable {
 
 private String id;
 
 public String getId() {
  return id;
 }

 public void setId(String id) {
  this.id = id;
 }

 private Prototype prototype;
 
 public Prototype getPrototype() {
  return prototype;
 }

 public void setPrototype(Prototype prototype) {
  this.prototype = prototype;
 }


 public Object clone(){ 
  try {
   return super.clone();
  } catch (CloneNotSupportedException e) {
   e.printStackTrace();
   return null;
  }  
 }

}
public class TestMain {

 public static void main(String[] args) {
  // TODO Auto-generated method stub
  testPrototype();
 }
 
 private static void testPrototype(){
  Prototype pro = new Prototype();
  pro.setName("original object");
  NewPrototype newObj = new NewPrototype();
  newObj.setId("test1");
  newObj.setPrototype(pro);
  
  NewPrototype copyObj = (NewPrototype)newObj.clone();
  copyObj.setId("testCopy");
  copyObj.getPrototype().setName("changed object");
  
  System.out.println("original object id:" + newObj.getId());
  System.out.println("original object name:" + newObj.getPrototype().getName());
  
  System.out.println("cloned object id:" + copyObj.getId());
  System.out.println("cloned object name:" + copyObj.getPrototype().getName());
  
 }

}
 

結果:
original object id:test1
original object name:changed object
cloned object id:testCopy
cloned object name:changed object

例項三: 深拷貝

public class Prototype implements Cloneable {
 private String name;

 public String getName() {
  return name;
 }

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

 public Object clone() {
  try { 
   return super.clone();
  } catch (CloneNotSupportedException e) {   
   e.printStackTrace();
   return null;
  }
 } 
 
}

public class NewPrototype implements Cloneable {
 
 private String id;
 
 public String getId() {
  return id;
 }

 public void setId(String id) {
  this.id = id;
 }

 private Prototype prototype;
 
 public Prototype getPrototype() {
  return prototype;
 }

 public void setPrototype(Prototype prototype) {
  this.prototype = prototype;
 }


 public Object clone(){
  NewPrototype ret = null;
  try {
   ret = (NewPrototype)super.clone();
   ret.prototype = (Prototype)this.prototype.clone();
   return ret;
  } catch (CloneNotSupportedException e) {
   e.printStackTrace();
   return null;
  }  
 }

}

public class TestMain {

 /**
  * @param args
  */
 public static void main(String[] args) {
  testDeepCopy();
 }
 
 private static void testDeepCopy(){
  Prototype pro = new Prototype();
  pro.setName("original object");
  NewPrototype newObj = new NewPrototype();
  newObj.setId("test1");
  newObj.setPrototype(pro);
  
  NewPrototype copyObj = (NewPrototype)newObj.clone();
  copyObj.setId("testCopy");
  copyObj.getPrototype().setName("changed object");
  
  System.out.println("original object id:" + newObj.getId());
  System.out.println("original object name:" + newObj.getPrototype().getName());
  
  System.out.println("cloned object id:" + copyObj.getId());
  System.out.println("cloned object name:" + copyObj.getPrototype().getName());
  
 }

}
 

結果:
original object id:test1
original object name:original object
cloned object id:testCopy
cloned object name:changed object

例項四: 利用序列化來做深複製
把物件寫道流裡的過程是序列化(Serilization)過程;把物件從流中讀出來是並行化(Deserialization)過程. 寫在流裡的是物件的一個拷貝,然後再從流裡讀出來重建物件.

public class PrototypeSe implements Serializable {

 private String name;

 public String getName() {
  return name;
 }

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

}

public class NewPrototypeSe implements Serializable {
 
 private String id;
 
 public String getId() {
  return id;
 }

 public void setId(String id) {
  this.id = id;
 }

 private PrototypeSe prototype;
 
 public PrototypeSe getPrototype() {
  return prototype;
 }

 public void setPrototype(PrototypeSe prototype) {
  this.prototype = prototype;
 }
 
 public Object deepClone(){
  try {
   ByteArrayOutputStream bo = new ByteArrayOutputStream();
   ObjectOutputStream oo = new ObjectOutputStream(bo);   
   oo.writeObject(this);   
   
   ByteArrayInputStream bi = new ByteArrayInputStream(bo.toByteArray());
   ObjectInputStream oi = new ObjectInputStream(bi);
   return oi.readObject(); 
  } catch (IOException | ClassNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
   return null;
  }
 }

}

public class TestDeepClone {

 public static void main(String[] args) {
  // TODO Auto-generated method stub
  PrototypeSe po = new PrototypeSe();
  po.setName("test1");
  NewPrototypeSe se = new NewPrototypeSe();
  se.setPrototype(po);
  
  NewPrototypeSe deepClone = (NewPrototypeSe)se.deepClone();
  deepClone.getPrototype().setName("test2");
  
  System.out.println("original name:" + se.getPrototype().getName());
  System.out.println("cloned name:" + deepClone.getPrototype().getName());

 }
}