Quelles sont les méthodes de conversion d'un objet Java en octet et d'un octet en objet ?

package com.byteToObject; 
import java.io.Serializable; 
public class student implements Serializable{
 
    private int sid;
    private String name;
    public int getSid() {
        return sid;
    }
    public void setSid(int sid) {
        this.sid = sid;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    } 
}

package com.byteToObject; 
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
 
public class Main { 
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        student stu = new student();
        stu.setSid(123);
        stu.setName("wanger");
        
        ByteArrayOutputStream byam = new ByteArrayOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(byam);
        oos.writeObject(stu);
        byte[] bytes = byam.toByteArray();
        System.out.println(bytes.toString());
        
        ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
        ObjectInputStream ois = new ObjectInputStream(bais);
        
        student s = (student)ois.readObject();
        System.out.println(s.getName());        
    }
}

@SuppressWarnings("unchecked")  
    public List<T> findByConditions(String hql,Object... conditions) throws Exception{  
        Session session = getSessionFactory().getCurrentSession();  
        Query query = session.createQuery(hql);  
        for (int i = 0; i < conditions.length; i++) {  
            query.setParameter(i, conditions[i]);  
        }  
        return query.list();  
    }