JAVA浅克隆和深克隆
浅克隆：被复制对象的所有变量和原来相同，而所有的对其他对象的引用仍指向原对象。即如果复制的对象修改复制对象的变量，原对象不会改变。而修改引用的对象，二者均会发生改变。
深复制(克隆)：被复制对象的所有变量都含有与原来的对象相同的值，除去那些引用其他对象的变量。那些引用其他对象的变量将指向被复制过来的新对象，而不再是原有的那些被引用的对象。深克隆就是把所有对象多复制了一遍。
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;
}
//浅复制
public Object clone(){
Object obj = null;
try {
obj = super.clone();
} catch (CloneNotSupportedException e) {
e.printStackTrace();
return null;
}
return obj;
}
/* 深复制 */
public Object deepClone() throws IOException, ClassNotFoundException {
/* 写入当前对象的二进制流 */
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(this);
/* 读出二进制流产生的新对象 */
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();
//浅复制
stu1.getTeacher().settName("tea2");
stu1.setAge(23);
System.out.println(stu1.getTeacher().gettName()+" "+stu.getTeacher().gettName());
System.out.println(stu1.getAge()+" "+stu.getAge());
}
}
//浅复制
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，前者为23，后者为22
//深复制
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，前者为23，后者为22
stu2.getTeacher().getName()的值和stu.getTeacher().getName()的的值不同，前者为tea3，后者为tea1
与 Math.sqrt())
