void flush

描述

所述java.io.FilterOutputStream.flush（）方法刷新此输出流并强制地写出来的任何缓冲的内容流中。

声明

以下是java.io.FilterOutputStream.flush（）方法的声明

public void flush()

参数

NA

返回值

此方法不返回任何值。

异常

IOException - 如果发生I / O错误。

实例

以下示例显示了java.io.FilterOutputStream.flush（）方法的用法。

package com.tutorialspoint;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;

public class FilterOutputStreamDemo {
   public static void main(String[] args) throws Exception {
      OutputStream os = null;
      FilterOutputStream fos = null;
      FileInputStream fis = null;
      int i = 0;
      char c;

      try {
         // create output streams
         os = new FileOutputStream("C://test.txt");
         fos = new FilterOutputStream(os);

         // writes byte to the output stream
         fos.write(65);

         // forces byte contents to written out to the stream
         fos.flush();

         // create output streams
         fis = new FileInputStream("C://test.txt");

         // read byte
         i=fis.read();

         // convert integer to characters
         c = (char)i;

         // prints
         System.out.print("Character read: "+ c);

      } catch(IOException e) {
         // if any I/O error occurs
         System.out.print("Close() is invoked prior to write()");
      } finally {
         // releases any system resources associated with the stream
         if(os!=null)
            os.close();
         if(fos!=null)
            fos.close();
      }
   }
}

让我们编译并运行上面的程序，这将产生以下结果

Close() is invoked prior to write()