Java Java.io.ObjectOutputStream.putFields() 方法

描述

java.io.ObjectOutputStream.putFields()方法检索用于缓冲要写入流中的持久字段的对象。调用writeFields方法时，会将字段写入流中。

声明

以下是java.io.ObjectOutputStream.putFields()方法的声明。

 public ObjectOutputStream.PutField putFields()

参数

不适用

返回值

此方法返回保存可序列化字段的类Putfield的实例。

异常

IOException如果发生I / O错误。

例子

以下示例显示java.io.ObjectOutputStream.putFields()方法的用法。

 
package com.jc2182;
import java.io.*;

public class ObjectOutputStreamDemo {
   public static void main(String[] args) {
      int i = 319874;
      
      try {
         // create a new file with an ObjectOutputStream
         FileOutputStream out = new FileOutputStream("test.txt");
         ObjectOutputStream oout = new ObjectOutputStream(out);

         // write something in the file
         oout.writeInt(i);
         oout.writeInt(1653984);

         // flush the stream
         oout.flush();

         // close the stream
         oout.close();

         // create an ObjectInputStream for the file we created before
         ObjectInputStream ois = new ObjectInputStream(new FileInputStream("test.txt"));

         // read and print an int
         System.out.println("" + ois.readInt());

         // read and print an int
         System.out.println("" + ois.readInt());
      } catch (Exception ex) {
         ex.printStackTrace();
      }
   }

   static public class Example implements Serializable {

      private void writeObject(ObjectOutputStream out) throws IOException {

         // write into the ObjectStreamField array the variable string
         ObjectOutputStream.PutField fields = out.putFields();
      }
   }
}

让我们编译并运行以上程序，这将产生以下结果-

 
319874 
1653984