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原型模式属于对象的创建模式。通过给出一个原型对象来指明所有创建的对象的类型，然后用复制这个原型对象的办法创建出更多同类型的对象。
原型模式又分为浅拷贝和深拷贝模式，类中只有简单数据类型的拷贝属于浅拷贝，如：
1 class Prototype implements Cloneable{ 2 private int id; 3 private String name; 4 public int getId() { 5 return id; 6 } 7 public void setId(int id) { 8 this.id = id; 9 } 10 public String getName() { 11 return name; 12 } 13 public void setName(String name) { 14 this.name = name; 15 } 16 17 public Object clone(){ 18 Prototype p = null; 19 try { 20 p = (Prototype) super.clone(); 21 } catch (CloneNotSupportedException e) { 22 e.printStackTrace(); 23 } 24 return p; 25 } 26 }
当类中持有其他类的对象的实例时，需要使用深拷贝，深拷贝又有两种方法，第一种是将持有的对象再分别进行浅拷贝，这种方法适合持有少量对象：
1 class Person implements Cloneable{ 2 private int id; 3 private String name; 4 public int getId() { 5 return id; 6 } 7 public void setId(int id) { 8 this.id = id; 9 } 10 public String getName() { 11 return name; 12 } 13 public void setName(String name) { 14 this.name = name; 15 } 16 17 public Object clone(){ 18 Person person = null; 19 try{ 20 person = (Person) super.clone(); 21 }catch (CloneNotSupportedException e) { 22 e.printStackTrace(); 23 } 24 return person; 25 } 26 } 27 28 class Prototype implements Cloneable{ 29 private boolean flag; 30 private Person person; 31 public boolean isFlag() { 32 return flag; 33 } 34 public void setFlag(boolean flag) { 35 this.flag = flag; 36 } 37 public Person getPerson() { 38 return person; 39 } 40 public void setPerson(Person person) { 41 this.person = person; 42 } 43 44 public Object clone(){ 45 Prototype p = null; 46 try{ 47 p = (Prototype) super.clone(); 48 p.person = (Person) person.clone(); 49 }catch(CloneNotSupportedException e){ 50 e.printStackTrace(); 51 } 52 return p; 53 } 54 }
另一种深拷贝的方法就是使用序列化：
1 import java.io.ByteArrayInputStream; 2 import java.io.ByteArrayOutputStream; 3 import java.io.IOException; 4 import java.io.ObjectInputStream; 5 import java.io.ObjectOutputStream; 6 import java.io.Serializable; 7 8 class Person implements Cloneable{ 9 private int id; 10 private String name; 11 public int getId() { 12 return id; 13 } 14 public void setId(int id) { 15 this.id = id; 16 } 17 public String getName() { 18 return name; 19 } 20 public void setName(String name) { 21 this.name = name; 22 } 23 24 public Object clone(){ 25 Person person = null; 26 try{ 27 person = (Person) super.clone(); 28 }catch (CloneNotSupportedException e) { 29 e.printStackTrace(); 30 } 31 return person; 32 } 33 } 34 35 class Prototype implements Serializable{ 36 private boolean flag; 37 private Person person; 38 public boolean isFlag() { 39 return flag; 40 } 41 public void setFlag(boolean flag) { 42 this.flag = flag; 43 } 44 public Person getPerson() { 45 return person; 46 } 47 public void setPerson(Person person) { 48 this.person = person; 49 } 50 51 public Object clone() { 52 try{ 53 ByteArrayOutputStream bos = new ByteArrayOutputStream(); 54 ObjectOutputStream oos = new ObjectOutputStream(bos); 55 oos.writeObject(oos); 56 57 ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray()); 58 ObjectInputStream ois = new ObjectInputStream(bis); 59 return ois.readObject(); 60 }catch(IOException e){ 61 e.printStackTrace(); 62 }catch(ClassNotFoundException e){ 63 e.printStackTrace(); 64 } 65 return null; 66 } 67 }
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原文地址：http://www.cnblogs.com/gsbm/p/4782445.html
