如何處理java.io.InvalidClassException？

Question

請告訴我，我做什麼此異常快到了，我不知道如何刪除它

java.io.InvalidClassException：applyonline.Applicant;局部類 不相容：流classdesc的serialVersionUID = 8333391523914038903， 本地類的serialVersionUID = -6432228733925744354

public class Applicant implements Serializable{ 

     public String getId() { 
      return id; 
     } 

     public String getPassword() { 
      return password; 
     } 

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

     public void setPassword(String password) { 
      this.password = password; 
     } 

     public Applicant() { 
     } 
     public boolean checkLogin(String id,String pasword) throws SQLException, IOException, ClassNotFoundException 
     { 
      db dbhandlerobj=new db(); 
      ArrayList<Object> appList; 
/* ----> */ appList = dbhandlerobj.getObject("Applicant","ApplicantInfo"); /* <------*/ 
      for(Object obj: appList) 
      { 
       Applicant app=(Applicant)obj; 
       System.out.println("ID:::::"+app.getId()); 
       if(app.getId().equals(id) && app.getPassword().equals(pasword)) 
       { 
        return true; 
       } 
      } 
      return false; 
     } 
     private String id; 
     private String password; 
    } 

OR映射器類

public class db { 
    Connection con; 
    String host="jdbc:derby://localhost:1527/Hamza"; 
    String userName="Hamza"; 
    String pasword="123"; 
    public db() throws SQLException { 

     this.con =DriverManager.getConnection(host, userName, pasword); 
    } 
    public void storeObject(Object object,String name) throws IOException, SQLException 
    { 
     PreparedStatement ps; 
     ByteArrayOutputStream baos =new ByteArrayOutputStream(); 
     ObjectOutputStream obos=new ObjectOutputStream(baos); 
     obos.writeObject(object); 
     obos.flush(); 
     obos.close(); 
     baos.close(); 
     byte []data=baos.toByteArray(); 
     String sql="insert into "+name+" values(?)"; 
     ps=con.prepareStatement(sql); 
     ps.setObject(1,data); 
     ps.executeUpdate(); 
    } 
    public ArrayList<Object> getObject(String tableName,String columnName) throws SQLException, IOException, ClassNotFoundException 
    { 
     PreparedStatement ps; 
     String sql="select * from "+tableName; 
     ps=con.prepareStatement(sql); 
     ResultSet rs=ps.executeQuery(); 
     ArrayList<Object> studentList=new ArrayList<Object>(); 
     while(rs.next()) 
     { 
      try (ByteArrayInputStream bais = new ByteArrayInputStream(rs.getBytes(columnName))) { 
       ObjectInputStream obis; 
       obis = new ObjectInputStream(bais); 
       studentList.add((Object)obis.readObject()); //<----ERROR IN THIS METHOD 
      } 
     }   
     return studentList; 
    } 
}** 

Answer 1

您使用的是不同版本的申請人類的。也許你首先將申請人類對象寫入數據庫，然後修改該類。這就是爲什麼你收到這個消息。

將對象再次寫入數據庫，然後嘗試反序列化它。