Java 输入/输出——处理流（ObjectIO）

　　Object流：直接将Object流写入或读出。

• TestObjectIO.java
• transient关键字（英文名：透明的，可以用来修饰成员变量（实例变量），transient修饰的成员变量（实例变量）在serializable序列化时不予考虑）
• serializable接口（可以被序列化，属于标记性接口，里面没有定义方法，打标机给编译器看，编译器看到了则认为该类可以被序列化）
• externalizable接口

 package com.zyjhandsome.io;

 import java.io.*;

 public class TestObjectIO {

     public static void main(String[] args) {
         // TODO Auto-generated method stub
         T t = new T();
         t.k = 8;

         try {
             FileOutputStream fos = new FileOutputStream("D:\\zhaoyingjun\\else\\Test\\TestObjectIO.log");
             ObjectOutputStream oos = new ObjectOutputStream(fos);
             oos.writeObject(t);
             oos.flush();
             oos.close();

             FileInputStream fis = new FileInputStream("D:\\zhaoyingjun\\else\\Test\\TestObjectIO.log");
             ObjectInputStream ois = new ObjectInputStream(fis);
             try {
                 T tReaded = (T)ois.readObject();
                 System.out.println(tReaded.i + " + " + tReaded.j + " + " + tReaded.d + " + " + tReaded.k + " = ");
                 System.out.println(tReaded.i + tReaded.j + tReaded.d + tReaded.k);

             } catch (ClassNotFoundException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
             }
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
     }
 }

 class T implements Serializable
 {
     int i = 10;
     int j = 9;
     double d = 2.3;
     int k = 15;
 }

　　输出结果：

 10 + 9 + 2.3 + 8 =
 29.3

　　结合transient关键字使用：

 package com.zyjhandsome.io;

 import java.io.*;

 public class TestObjectIO {

     public static void main(String[] args) {
         // TODO Auto-generated method stub
         T t = new T();
         t.k = 8;

         try {
             FileOutputStream fos = new FileOutputStream("D:\\zhaoyingjun\\else\\Test\\TestObjectIO.log");
             ObjectOutputStream oos = new ObjectOutputStream(fos);
             oos.writeObject(t);
             oos.flush();
             oos.close();

             FileInputStream fis = new FileInputStream("D:\\zhaoyingjun\\else\\Test\\TestObjectIO.log");
             ObjectInputStream ois = new ObjectInputStream(fis);
             try {
                 T tReaded = (T)ois.readObject();
                 System.out.println(tReaded.i + " + " + tReaded.j + " + " + tReaded.d + " + " + tReaded.k + " = ");
                 System.out.println(tReaded.i + tReaded.j + tReaded.d + tReaded.k);

             } catch (ClassNotFoundException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
             }
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
     }
 }

 class T implements Serializable
 {
     int i = 10;
     int j = 9;
     double d = 2.3;
transient int k = 15;
 }

　　输出结果：

 10 + 9 + 2.3 + 0 =
 21.3