java-io 输入流到输出流，使用一个byte[]数组做缓存

	private void writeResponse(InputStream zin, OutputStream out) throws Exception {
		byte[] bytes = buffers.get();
		int bytesRead = -1;
		while ((bytesRead = zin.read(bytes)) != -1) { //读到-1说明已经读取完了
			out.write(bytes, 0, bytesRead); // 从byte[]数组写出到OutputStream
		}
	}