java - 通过反序列化代码更改数据

Question

我只是想知道如何更改反序列化中的数据。我的程序需要:

询问用户是否要更改学生信息并将新数据存储在文本文件中。

这是我的代码:

import java.util.*;
import java.io.*;
import java.io.Serializable;

public class Deserialization{

    public static void main(String [] args) {

       Student st1 = null;
       Student st2 = null;
       Student st3 = null;
       String opcion=null;
       Scanner lol=new Scanner (System.in);

      try {
         FileInputStream fileIn = new FileInputStream("input.ser");
         ObjectInputStream in = new ObjectInputStream(fileIn);
         st1 = (Student) in.readObject();
         st2 = (Student) in.readObject();
         st3 = (Student) in.readObject();
         do{ //HERE IS WHEREI WANT TO ASK MY USER AND REALIZE IT
            System.out.println("Want to change?\n");
            opcion=lol.next();
             lol.nextLine();
         }while(opcion.equals("y")||opcion.equals("Y"));
         in.close();
         fileIn.close();
      } catch (IOException i) {
         i.printStackTrace();
         return;
      } catch (ClassNotFoundException c) {
         System.out.println("Class not found");
         c.printStackTrace();
         return;
      }

      System.out.println("Deserialized File...");
      System.out.println("Student 1");
      System.out.println("Name: " +st1.name);
      System.out.println("ID: " +st1.id);
      System.out.println("Average: " +st1.average);
      System.out.println("Student 2");
      System.out.println("Name: " +st2.name);
      System.out.println("ID: " +st2.id);
      System.out.println("Average: " +st2.average);
      System.out.println("Student 3");
      System.out.println("Name: " +st3.name);
      System.out.println("ID: " +st3.id);
      System.out.println("Average: " +st3.average);
   }
}

化解部分

Answer 1

假设您有一个像这样的学生类(class) -

public class Student {
  private String Name;
  private int ID;
  private int Average;
  /**
   * @return the name
   */
  public String getName() {
    return Name;
  }
  /**
   * @param name the name to set
   */
  public void setName(String name) {
    Name = name;
  }
  /**
   * @return the iD
   */
  public int getID() {
    return ID;
  }
  /**
   * @param iD the iD to set
   */
  public void setID(int iD) {
    ID = iD;
  }
  /**
   * @return the average
   */
  public int getAverage() {
    return Average;
  }
  /**
   * @param average the average to set
   */
  public void setAverage(int average) {
    Average = average;
  }


}

反序列化后，您将从文件中读取一个对象，现在您想要修改 Student 对象。

 st1 = (Student) in.readObject();
 st2 = (Student) in.readObject();
 st3 = (Student) in.readObject();

这里有 st1、st2 和 st3 Student 对象。您可以通过调用Student对象的setter方法来修改st1名称。例如，如果您想修改学生姓名，您只需调用

st1.setName("modifyName");

修改后，您可以按照常规方式将 st1 修改后的对象写入文件中。