Java中IO流的BufferedOutputStream和FileOutputStream对比

FileOutputStream fileOutputStream = new FileOutputStream("D:\\1.txt");

// out 写
BufferedOutputStream in = new BufferedOutputStream(new FileOutputStream("D:\\out.txt"),8192);
// in  读
BufferedInputStream bufferedInputStream = new BufferedInputStream(new FileInputStream("D:\\in.txt"),8192);

    volatile boolean run = true; // 标志位
   // 不带缓冲区 每次只写一个字节
    @Test
    public void fileWriteOneByte() throws IOException {
        FileOutputStream fileOutputStream = new FileOutputStream("D:\\FileOutputStream_one.txt");
        // 延时5秒
        fiveSeconds();
        while (run){
            // 每次写一个字节
            fileOutputStream.write(1);
        }
        fileOutputStream.flush();
        fileOutputStream.close();
    }
    // 带缓冲区-->每次只写一个字节
    @Test
    public void bufferWriteOneByte() throws IOException {
        FileOutputStream fileOutputStream = new FileOutputStream("D:\\BufferedOutputStream_one.txt");
        BufferedOutputStream bufferedInputStream = new BufferedOutputStream(fileOutputStream);
        // 延时5秒
        fiveSeconds();
        while (run){
            // 每次写一个字节
            bufferedInputStream.write((byte)1);
        }
        bufferedInputStream.flush();
        bufferedInputStream.close();
    }
    /**
     * 延时5秒
     */
    private void fiveSeconds(){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    // 睡5秒
                    Thread.sleep(5000);
                    // 跳出死循环
                    run = false;
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }

   volatile boolean run = true;
    // 每次写81920个字节
    @Test
    public void file() throws IOException {
        byte[] bytes = new byte[81920];
        FileOutputStream fileOutputStream = new FileOutputStream("D:\\FileOutputStream_81920.txt");
        // 延时5秒
        fiveSeconds();
        while (run){
            // 每次写入 81920 个字节
            fileOutputStream.write(bytes);
        }
        fileOutputStream.flush();
        fileOutputStream.close();
    }
    // 每次写81920个字节
    @Test
    public void bufferFile() throws IOException {
        byte[] bytes = new byte[81920];
        FileOutputStream fileOutputStream = new FileOutputStream("D:\\BufferedOutputStream_81920.txt");
        BufferedOutputStream bufferedInputStream = new BufferedOutputStream(fileOutputStream,81920);
        // 延时5秒
        fiveSeconds();
        while (run){
            // 每次写入 81920 个字节
            bufferedInputStream.write(bytes);
        }
        bufferedInputStream.flush();
        bufferedInputStream.close();
    }
    // 延时5秒
    private void fiveSeconds(){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    // 睡5秒
                    Thread.sleep(5000);
                    // 跳出死循环
                    run = false;
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }