java serialization object serializable instance of reading and writing data

package com.chen.seriaizable;
import java.io.Serializable;
import java.util.List;
@SuppressWarnings("serial")
public class Student implements Serializable
{
 private String name;

 private String id;

 private int age;

 private List<Student> students;
 public String getName()
 {
  return name;
 }
 public void setName(String name)
 {
  this.name = name;
 }
 public String getId()
 {
  return id;
 }
 public void setId(String id)
 {
  this.id = id;
 }
 public int getAge()
 {
  return age;
 }
 public void setAge(int age)
 {
  this.age = age;
 }
 public List<Student> getStudents()
 {
  return students;
 }
 public void setStudents(List<Student> students)
 {
  this.students = students;
 }
 @Override
 public String toString()
 {
  StringBuffer stringBuffer = new StringBuffer();
  stringBuffer.append("id：" + this.id).append("\n");
  stringBuffer.append("name：" + this.name).append("\n");
  stringBuffer.append("age：" + this.age).append("\n");

  return stringBuffer.toString();
 }
}

package com.chen.seriaizable;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
import java.util.List;
public class SaveStudent
{
 private Student student;
 // 序列化文件保存位置
 private String path = "C:/student.Serializable";

 public void writeStudent()
 {
  List<Student> students = new ArrayList<Student>();
  student = new Student();

  Student student1 = new Student();
  student1.setAge(1);
  student1.setId("1");
  student1.setName("张1");
  students.add(student1);

  Student student2 = new Student();
  student2.setAge(2);
  student2.setId("2");
  student2.setName("张2");
  students.add(student2);

  Student student3 = new Student();
  student3.setAge(3);
  student3.setId("3");
  student3.setName("张3");
  students.add(student3);

  Student student4 = new Student();
  student4.setAge(4);
  student4.setId("4");
  student4.setName("张4");

  Student student41 = new Student();
  student41.setAge(41);
  student41.setId("41");
  student41.setName("张41");
  List<Student> students4 = new ArrayList<Student>();
  students4.add(student41);

  student4.setStudents(students4);

  students.add(student4);
 
  student.setAge(500);
  student.setId("100");
  student.setName("张A000");
  student.setStudents(students);
  try
  {
   ObjectOutputStream objectOutputStream = new ObjectOutputStream(new FileOutputStream(path));

   objectOutputStream.writeObject(student);

   objectOutputStream.close();
  }
  catch (IOException e)
  {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  System.out.println("写完");
 }

 public void readStudent()
 {
  try
  {
   ObjectInputStream objectInputStream = new ObjectInputStream(new FileInputStream(path));

   student = (Student) objectInputStream.readObject();

   System.out.println(student.getAge());

   objectInputStream.close();
  }
  catch (Exception e)
  {
   e.printStackTrace();
  }
  System.out.println("读完");
 }

 @Override
 public String toString()
 {
  readStudent();
  StringBuffer stringBuffer = new StringBuffer(100);

  studentToString(stringBuffer, student);

  return stringBuffer.toString();
 }

 public void studentToString(StringBuffer stringBuffer, Student studentObj)
 {
  if (student != null)
  {
   stringBuffer.append("id：" + studentObj.toString()).append("\n");
   if (studentObj.getStudents() != null)
   {
    stringBuffer.append("\n[\n");
    for (Student bean : studentObj.getStudents())
    {
     studentToString(stringBuffer, bean);
    }
    stringBuffer.append("\n]\n");
   }
  }
 }
}

package com.chen.seriaizable;
public class Test
{
 /**
  * @param args
  */
 public static void main(String[] args)
 {
  SaveStudent saveStudent = new SaveStudent();
  // 1 先执行写入文件
//  saveStudent.writeStudent();
  // 2 再读取
  System.out.println(saveStudent);
  System.out.println("读完");
 }
}