JAVA淺克隆和深克隆

淺克隆：被復制對象的所有變量和原來相同，而所有的對其他對象的引用仍指向原對象。即如果復制的對象修改復制對象的變量，原對象不會改變。而修改引用的對象，二者均會發生改變。

深復制(克隆)：被復制對象的所有變量都含有與原來的對象相同的值，除去那些引用其他對象的變量。那些引用其他對象的變量將指向被復制過來的新對象，而不再是原有的那些被引用的對象。深克隆就是把所有對象多復制了一遍。

public class Student implements Cloneable,Serializable {

private String name;

private int age;

private Teacher teacher;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}

public Teacher getTeacher() {

return teacher;

}

public void setTeacher(Teacher teacher) {

this.teacher = teacher;

}

//淺復制

public Object clone(){

Object obj = null;

try {

obj = super.clone();

} catch (CloneNotSupportedException e) {

e.printStackTrace();

return null;

}

return obj;

}

/* 深復制 */

public Object deepClone() throws IOException, ClassNotFoundException {

/* 寫入當前對象的二進制流 */

ByteArrayOutputStream bos = new ByteArrayOutputStream();

ObjectOutputStream oos = new ObjectOutputStream(bos);

oos.writeObject(this);

/* 讀出二進制流產生的新對象 */

ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

ObjectInputStream ois = new ObjectInputStream(bis);

return ois.readObject();

}

}

public class Teacher implements Serializable{

private String tName;

public Teacher() {

super();

}

public Teacher(String tName) {

super();

this.tName = tName;

}

public String gettName() {

return tName;

}

public void settName(String tName) {

this.tName = tName;

}

}

import java.io.IOException;

public class Test {

/**

* @param args

*/

public static void main(String[] args) throws ClassNotFoundException, IOException {

Student stu = new Student();

stu.setAge(22);

stu.setName("stu1");

stu.setTeacher(new Teacher("Tea1"));

Student stu1 = (Student) stu.clone();

//淺復制

stu1.getTeacher().settName("tea2");

stu1.setAge(23);

System.out.println(stu1.getTeacher().gettName()+"? "+stu.getTeacher().gettName());

System.out.println(stu1.getAge()+"? "+stu.getAge());

}

}

//淺復制

stu1.getTeacher().gettName()的值和stu.getTeacher().gettName()相同，被修改之后的值

stu1.getAge()的值和stu.getAge()的值不同，前者為23，后者為22

//深復制

Student stu2 = (Student) stu.deepClone();

stu2.getTeacher().settName("tea3");

stu2.setAge(23);

System.out.println(stu2.getAge()+” ”+stu.getAge());

System.out.println(stu2.getTeacher().gettName()+"? "+stu.getTeacher().gettName());

stu2.getAge()的值和stu.getAge()的值不同，前者為23，后者為22

stu2.getTeacher().getName()的值和stu.getTeacher().getName()的的值不同，前者為tea3，后者為tea1