java.lang.Cloneable的理解

浏览数：18 / 时间：2015年06月08日

以前也用过这个接口，那时是直接所有的东西都自己写了，也没发现问题。最近无意间发现这个接口的实现并不是想象中的那样，所以稍微研究了下，给大家分享一下。

步骤：1、建立两个简单的POJO:Teacher和Student

2、Teacher类实现了Cloneable接口，重写clone方法

3、在main方法中建立teacher，然后clone,比较teacher和clone出来的teacher

Teacher类：

public class Teacher implements Cloneable,Serializable{

   private String name;

   private String sex;

   private int age;

   private List<Student> list;

   public String getName() {
       return name;
   }

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

   public String getSex() {
       return sex;
   }

   public void setSex(String sex) {
       this.sex = sex;
   }

   public List<Student> getList() {
       return list;
   }

   public void setList(List<Student> list) {
       this.list = list;
   }

   public int getAge() {
       return age;
   }

   public void setAge(int age) {
       this.age = age;
   }

   @Override
   protected Teacher clone() throws CloneNotSupportedException {

       Teacher t = (Teacher)super.clone();

       return t;
   }

   public Teacher deepClone() throws IOException, ClassNotFoundException
   {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        ObjectOutputStream temp_out = new ObjectOutputStream(out);
        temp_out.writeObject(this);

        ByteArrayInputStream input = new ByteArrayInputStream(out.toByteArray());
        ObjectInputStream temp_input = new ObjectInputStream(input);
        return (Teacher) temp_input.readObject();
   }
}

Student类：

public class Student implements Serializable{

   private String stName;

   private String stSex;

   public String getStName() {
       return stName;
   }

   public void setStName(String stName) {
       this.stName = stName;
   }

   public String getStSex() {
       return stSex;
   }

   public void setStSex(String stSex) {
       this.stSex = stSex;
   }
}

main：

public class MainTest {

   public static void main(String[] args) throws CloneNotSupportedException, ClassNotFoundException, IOException {
       List<Student> list = new ArrayList<Student>();

       Student st = new Student();

       st.setStName("stname");

       st.setStSex("f");

       list.add(st);

       Teacher te = new Teacher();

       te.setAge(19);

       te.setList(list);

       te.setName("tename");

       te.setSex("tesex");

        Teacher cl = te.clone();

        cl.setAge(12);

        System.out.println("淺複製"+ (cl == te));

        //内存中的地址
        System.out.println(cl.getName() == te.getName());

        System.out.println(cl.getList() == te.getList());

        System.out.println("source:"+te.getAge()+"<==>clone:"+cl.getAge());


        Teacher deep = te.deepClone();