【JAVA产生对象的几种方式】

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

/**
* java生成对象的几种方式
*   1、new
*   2、反射
*      Class.forName
*      类.class
*      对象.getClass()
*   3、clone
*      必须实现Cloneable接口,实现protected Object clone()方法
*   4、序列化

1.概念

　　序列化：把Java对象转换为字节序列的过程。
　　反序列化：把字节序列恢复为Java对象的过程。

2.用途

  　　对象的序列化主要有两种用途：
  　　1）把对象的字节序列永久地保存到硬盘上，通常存放在一个文件中；
  　　2）在网络上传送对象的字节序列。

* @author Administrator

*/
public class Demo1 {

/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
//一、使用new

    Student s = new Student();
      s.print();

   //二、使用反射
  Class c = Class.forName("Student");
  Student c1=(Student)c.newInstance();
  c1.print();

  System.out.println("1、通过类本身获得对象");
   Class clazz = Student.class;
   Student s11=(Student)clazz.newInstance();
   s11.print();

   Student student1 = new Student();
   clazz = student1.getClass();
   Student s12=(Student)clazz.newInstance();
   s12.print();

//三、使用clone

  /**
   * implements Cloneable
   * protected Object clone()
   */
  Student s1 = (Student) s.clone();
  s1.print();
//  Exception in thread "main" java.lang.CloneNotSupportedException:


   //四、使用Serializable
  System.out.println(" 序列化对象 ");
   //序列化对象
        ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("C:\\objectFile.obj"));
        Student student = new Student();
        out.writeObject(student);    //写入student对象
        out.close();

        System.out.println(" 反序列化对象 ");
        //反序列化对象
        ObjectInputStream in = new ObjectInputStream(new FileInputStream("C:\\objectFile.obj"));
        Student obj3 = (Student) in.readObject();
        obj3.print();
        in.close();
}

}

-----------------------------------

import java.io.Serializable;

public class Student implements Serializable{
private String id;

private String name;

private int age;

public Student(){
  System.out.println(" Student Constructor");
}

public void print() {
  System.out.println(" Student print method called!!!!");
}

@Override
protected Object clone() throws CloneNotSupportedException {
  // TODO Auto-generated method stub
  return super.clone();
}
public Student(String id, String name, int age) {
  super();
  this.id = id;
  this.name = name;
  this.age = age;
  System.out.println(" Student(id,name,age) Constructor");
}

public String getId() {
return id;
}

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

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;
}

}

【JAVA产生对象的几种方式】

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