public static long copy(InputStream inputStream, OutputStream outputStream, int bufferSize) throws IOException {
		byte[] buffer = new byte[bufferSize];
		long count = 0;
		int n;
		while ( -1 != ( n = inputStream.read( buffer ) ) ) {
			outputStream.write( buffer, 0, n );
			count += n;
		}
		return count;

	}
public static long copy(InputStream inputStream, OutputStream outputStream, int bufferSize) throws IOException {
		byte[] buffer = new byte[bufferSize];
		long count = 0;
		int n;
		while ( -1 != ( n = inputStream.read( buffer ) ) ) {
			outputStream.write( buffer, 0, n );
			count += n;
		}
		return count;

	}
public static long copy ( InputStream inputStream , OutputStream outputStream , int bufferSize ) throws IOException { byte [ ] buffer = new byte [ bufferSize ] ; long count = 0 ; int n ; while ( - 1 != ( n = inputStream . read ( buffer ) ) ) { outputStream . write ( buffer , 0 , n ) ; count += n ; } return count ; }
input->output字节流copy
@param inputStream
@param outputStream
@param bufferSize
@return
@throws IOException
input - > output字节流copy