/*

 * 字节输出流的缓冲流  作用  提高效率

 * 继承OutputStream

 * 构造方法 new BufferedOutputStream(OutputStream out);

 *

 * */

public class BufferedOutputStreamDemo {

    public static void main(String[] args) throws Exception {

    //  1创建字节输出流   绑定文件

        //FileOutputStream fos =new FileOutputStream("c:\\buffer");

BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("c:\\buffer"));

     bos.write(65);//自动查码表  utf-8  0  1

     //输出字符串

     byte[] b= "hello world".getBytes();

     bos.write(b);

    //截取

     bos.write(b, 3, 2);

     bos.close();

    }

}

/*

 *   字节输入流的缓冲流

 *   继承InputStream

 *   构造方法

 *

 * */

public class BufferedInputStreamDemo {

    public static void main(String[] args) throws Exception {

        //1  创建字节输入流的缓冲流对象

        BufferedInputStream b = new BufferedInputStream(new

                FileInputStream("c:\\buffer"));

        byte[] bs = new byte[1024];

        b.close();

        int len = 0;

        while((len=b.read(bs))!=-1){

            System.out.print(new String(bs,0,len));

        }

     }

}

public class BufferedReaderDemo {

    public static void main(String[] args) throws Exception {

        //创建字符输入缓冲流对象

        BufferedReader bu =new BufferedReader(new FileReader("c:\\bu.txt"));

        String len = null;

        while((len=bu.readLine())!=null){

            System.out.println(len);

        }

        bu.close();

    }

}

/*字符输出缓冲流

 * write();

 *  构造方法 BufferedWriter(Writer w);

 *  new line() 写换行    \r\n

 *            linux   \n

 * */

public class BufferedWriterDemo {

    public static void main(String[] args) throws IOException {

        //创建字符输出流  封装文件

        FileWriter fWriter = new FileWriter("c://bu.txt");

        BufferedWriter bufferedWriter = new BufferedWriter(fWriter);

        bufferedWriter.write("您好");

        bufferedWriter.newLine();//换行

        bufferedWriter.write(100);

        bufferedWriter.flush();

        bufferedWriter.write("床前明月光");

        bufferedWriter.close();

    }

}

/*

 *  文件的复制方式

 *  1 字节流读写单个字节

 *  2 字节流读写字节数组   2405ms

 *  3 字节流缓冲区 读写单个字节   4855ms

 *  4 字节流缓冲区读写字节数组  697ms

 * */

public class Copy {

    public static void main(String[] args) throws Exception {

        long timeStart = System.currentTimeMillis();

        copy4(new File("c:\\liu.mp4"), new File("d:\\liu.mp4"));

        long end = System.currentTimeMillis();

        System.out.println(end-timeStart);

    }

    // 4 字节流缓冲区读写字节数组

    public static void copy4(File src,File desc) throws Exception{

        BufferedInputStream bu = new BufferedInputStream(new FileInputStream(src));

        BufferedOutputStream ou = new BufferedOutputStream(new FileOutputStream(desc));

      int len = 0;

      byte[] b=new byte[1024*10];

      while((len=bu.read(b))!=-1){

          ou.write(b,0,len);

      }

      ou.close();

      bu.close();

    }

    //3 字节流缓冲区 读写单个字节

    public static void copy3(File src,File desc) throws Exception{

        BufferedInputStream bu = new BufferedInputStream(new FileInputStream(src));

        BufferedOutputStream ou = new BufferedOutputStream(new FileOutputStream(desc));

      int len = 0;

      while((len=bu.read())!=-1){

          ou.write(len);

      }

      ou.close();

      bu.close();

    }

    //2 字节流读写字节数组

    public static void  copy2(File src,File desc) throws Exception{

        FileInputStream fis = new FileInputStream(src);

        FileOutputStream fos = new FileOutputStream(desc);

        int len = 0;

        byte[] b =new byte[1024*10];

        while((len=fis.read(b))!=-1){

            fos.write(b,0,len);

        }

        fos.close();

        fis.close();

    }

        //1 字节流读写单个字节

    public static void  copy1(File src,File desc) throws Exception{

        FileInputStream fis = new FileInputStream(src);

        FileOutputStream fos = new FileOutputStream(desc);

        int len = 0;

        while((len=fis.read())!=-1){

            fos.write(len);

        }

        fos.close();

        fis.close();

    }

}