ObjectOutputStream 追加写入读取错误 - 自己的实现方案

本篇博客灵感来自http://blog.csdn.net/chenssy/article/details/13170015

问题描述、问题出现的原因、尝试解决办法，请参见鄙人上一编博客。

上一编文章解决ObjectOutputStream 追加写入读取错误问题的方法是自定义了一个ObjectOutputStream子类，我觉得不如用匿名内部类实现方便，于是自我研究写出以下两种方案。个人更推崇方案二

方案一：

 package packa;

 import java.io.*;

 class ObjectInputOutputStream2
 {
     public static void main(String[] args)throws Exception
     {
         writeObj();
         readObj();
     }

     private static void writeObj()throws Exception
     {
         final File f = new File("person.object");
         ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("person.object", true))
         {
             protected  void writeStreamHeader()throws IOException
             {
                 if (!f.exists() || (f.exists() && 0 == f.length()))
                 {
                     super.writeStreamHeader();
                 }
             }
         };

         oos.writeObject(new Person("liu", 30, "kr"));
         oos.writeObject(new Person2("liu", "kr", "kr2"));
         oos.writeObject(new Person3(10, 30, 50));

         oos.close();
     }

     private static void readObj()throws Exception
     {
         ObjectInputStream ois = new ObjectInputStream(new FileInputStream("person.object"));

         try
         {
             while(true)
             {
                 System.out.println(ois.readObject());
             }
         }
         catch (Exception e)
         {
             System.out.println(e.toString());
         }

         ois.close();
     }
 }

方案二：

 package packa;

 import java.io.*;

 class ObjectInputOutputStream
 {
     public static void main(String[] args)throws Exception
     {
         writeObj();
         readObj();
     }

     static ObjectOutputStream  getObjectOutputStreamInstance(final OutputStream os, final File f) throws IOException
     {
         return  new ObjectOutputStream(os)
         {
             protected  void writeStreamHeader()throws IOException
             {
                 if (!f.exists() || (f.exists() && 0 == f.length()))
                 {
                     super.writeStreamHeader();
                 }
             }
         };
     }

     private static void writeObj()throws Exception
     {
         ObjectOutputStream oos = getObjectOutputStreamInstance(new FileOutputStream("person.object", true), new File("person.object"));
         oos.writeObject(new Person("liu", 30, "kr"));
         oos.writeObject(new Person2("liu", "kr", "kr2"));
         oos.writeObject(new Person3(10, 30, 50));

         oos.close();
     }

     private static void readObj()throws Exception
     {
         ObjectInputStream ois = new ObjectInputStream(new FileInputStream("person.object"));

         try
         {
             while(true)
             {
                 System.out.println(ois.readObject());
             }
         }
         catch (Exception e)
         {
             System.out.println(e.toString());
         }

         ois.close();
     }
 }

 package packa;

 import java.io.*;

 class Person implements Serializable
 {
     public static final long serialVersionUID = 44L;

     String name;
     transient int age;
     static String country = "cn";

     Person(String name, int age, String country)
     {
         this.name = name;
         this.age = age;
         this.country = country;
     }

     public String toString()
     {
         return name + " " + age + " " + country;
     }

 }
 class Person2 implements Serializable
 {
     public static final long serialVersionUID = 45L;

     String name;
     String country;
     String country2;

     Person2(String name, String country, String country2)
     {
         this.name = name;
         this.country = country;
         this.country2 = country2;
     }

     public String toString()
     {
         return name + " " + country + " " + country2;
     }

 }
 class Person3 implements Serializable
 {
     public static final long serialVersionUID = 46L;

     int age;
     int age2;
     int age3;

     Person3(int age, int age2, int age3)
     {
         this.age = age;
         this.age2 = age2;
         this.age3 = age3;
     }

     public String toString()
     {
         return age + " " + age2 + " " + age3;
     }

 }