BufferedInputStream leer los datos

constructor:

public BufferedInputStream(InputStream in)：
public BufferedInputStream(InputStream in,int size)：

//public BufferedInputStream(InputStream in)：
		//封装数据
		BufferedInputStream bis=new BufferedInputStream(new FileInputStream("a.txt"));
		 //读取数据
//		int len;
//		while((len=bis.read())!=-1){
//			System.out.print((char)len);
//		}
		int len;
		byte[] bt=new byte[1024];
		while((len=bis.read(bt))!=-1){
			System.out.print(new String(bt,0,len));
		}
		
		//释放资源
		bis.close();