java在线浏览PDF+PNG（上线项目）

public static void browsePDF(HttpServletResponse response, String PDF) throws IOException {
		response.setContentType("application/pdf");
		FileInputStream in = new FileInputStream(new File(PDF));
		OutputStream out = response.getOutputStream();
		byte[] b = new byte[512];
		while ((in.read(b)) != -1) {
			out.write(b);
		}
		out.flush();
		in.close();
		out.close();
	}
	public static void browsePNG(HttpServletResponse response, String PNG){
		InputStream is = null;
		OutputStream os = null;
		try {
			response.setContentType("text/html; charset=UTF-8");
			response.setContentType("image/png");
			File filePNG = new File(PNG);
			response.addHeader("Content-Length", "" + filePNG.length());
			is = new FileInputStream(filePNG);
			os = response.getOutputStream();
			IOUtils.copy(is, os);
		} catch (Exception e) {
			logger.info("异常-->{}",e);
		} finally {
			try {
				if (os != null) {
					os.flush();
					os.close();
				}
				if (is != null) {
					is.close();
				}
			} catch (IOException e) {
			}
		}
	}