序列化问题

不是说static 变量不能序列化吗？但如下程序：
import java.io.*;
public class DataObject implements Serializable
{
private static int i=0;
private String word=" ";
public void setWord(String word)
{
this.word=word;
}
public void setI(int i)
{
this.i=i;
}
public String toString()
{
return "word:"+word+";i="+i;
}
public static void main(String[] args) throws ClassNotFoundException,FileNotFoundException,IOException
{
DataObject object=new DataObject();
object.setWord("123");
object.setI(2);
System.out.println(object);
ObjectOutputStream out=new ObjectOutputStream(new FileOutputStream("lql.out"));
out.writeObject(object);
ObjectInputStream in=new ObjectInputStream(new FileInputStream("lql.out"));
DataObject object2=(DataObject)in.readObject();
System.out.println(object2);
}
}
运动后：word=123;i=2;
word=123;i=2;
这如何解释呢？
请帮忙一下，谢谢！