Java Java.io.BufferedWriter.flush()用法及代码示例

描述

这个java.io.BufferedWriter.flush()方法将字符从写入缓冲区刷新到字符或字节流作为预期目标。

声明

以下是声明java.io.BufferedWriter.flush()方法。

public Writer 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。

示例

下面的例子展示了 java.io.BufferedWriter.flush() 方法的用法。

package com.tutorialspoint;

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.StringWriter;

public class BufferedWriterDemo {
   public static void main(String[] args) throws IOException {
      StringWriter sw = null;
      BufferedWriter bw = null;
      String letters = "ABCDEFGHIJK";
      
      try {
         // create string writer
         sw = new StringWriter();
         
         //create buffered writer
         bw = new BufferedWriter(sw);
         
         // for each character in the string
         for (char c:letters.toCharArray()) {
            
            // append character to the writer
            bw.append(c);
            
            // flush the characters to the intended stream
            bw.flush();
            
            // print string buffer from string writer
            System.out.println(sw.getBuffer());
         }
      } catch(IOException e) {
         // if I/O error occurs
         e.printStackTrace();
      } finally {
         // releases any system resources associated with the stream
         if(sw!=null)
            sw.close();
         if(bw!=null)
            bw.close();
      }
   }
}

让我们编译并运行上面的程序，这将产生以下结果——

A
AB
ABC
ABCD
ABCDE
ABCDEF
ABCDEFG
ABCDEFGH
ABCDEFGHI
ABCDEFGHIJ
ABCDEFGHIJK