Java ObjectOutputStream writeLong()用法及代码示例

ObjectOutputStream类writeLong()方法

• writeLong() 方法可在java.io包。
• writeLong() 方法用于写入给定的 8 字节long值。
• writeLong() 方法是一个非静态方法，它只能通过类对象访问，如果我们尝试使用类名访问方法，那么我们将得到一个错误。
• writeLong() 方法可能会在写入 long 时抛出异常。
  IOException:在写入输出流时出现任何输入/输出错误时，可能会抛出此异常。

用法:

    public void writeLong(long value);

参数：

• long value– 表示要写入的 long 值。

返回值：

该方法的返回类型是void，它什么都不返回。

例：

// Java program to demonstrate the example 
// of void writeLong(long value) method of 
// ObjectOutputStream

import java.io.*;

public class WriteLongOfOOS {
 public static void main(String[] args) throws Exception {
  // Instantiates ObjectOutputStream , ObjectInputStream 
  // FileInputStream and FileOutputStream
  FileOutputStream file_out_stm = new FileOutputStream("D:\\includehelp.txt");
  ObjectOutputStream obj_out_stm = new ObjectOutputStream(file_out_stm);
  FileInputStream file_in_stm = new FileInputStream("D:\\includehelp.txt");
  ObjectInputStream obj_in_stm = new ObjectInputStream(file_in_stm);

  // By using writeLong() method is to
  // write the long to the stream		
  obj_out_stm.writeLong(5411489332534l);
  obj_out_stm.writeLong(234773224114l);

  obj_out_stm.flush();

  // By using readLong() method is to 
  // read the long and convert it into long
  for (int i = 0; i < 2; ++i) {
   long l = (long) obj_in_stm.readLong();
   System.out.println("obj_in_stm.readLong():" + l);
  }

  // By using close() method is to 
  // close all the streams 
  System.out.println("Stream Shutdown...");

  file_in_stm.close();
  file_out_stm.close();
  obj_in_stm.close();
  obj_out_stm.close();
 }
}

输出

obj_in_stm.readLong():5411489332534
obj_in_stm.readLong():234773224114
Stream Shutdown...