spring - 如何在 JAVA 的 rest API 中将图像返回给浏览器？

Question

我想要一个图像，同时我点击一个 API，比如 localhost:8080:/getImage/app/path={imagePath}

当我点击这个 API 时，它会返回一张图片。

这可能吗？

实际上，我已经试过了，但它给了我一个错误。这是我的代码，

@GET
@Path("/app")
public BufferedImage getFullImage(@Context UriInfo info) throws MalformedURLException, IOException {
    String objectKey = info.getQueryParameters().getFirst("path");

    return resizeImage(300, 300, objectKey);
}


public static BufferedImage resizeImage(int width, int height, String imagePath)
        throws MalformedURLException, IOException {
    BufferedImage bufferedImage = ImageIO.read(new URL(imagePath));
    final Graphics2D graphics2D = bufferedImage.createGraphics();
    graphics2D.setComposite(AlphaComposite.Src);
    // below three lines are for RenderingHints for better image quality at cost of
    // higher processing time
    graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
    graphics2D.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
    graphics2D.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
    graphics2D.drawImage(bufferedImage, 0, 0, width, height, null);
    graphics2D.dispose();
    System.out.println(bufferedImage.getWidth());
    return bufferedImage;
}

我的错误，

java.io.IOException: The image-based media type image/webp is not supported for writing

有什么方法可以在 java 中点击任何 URL 时返回图像吗？

Answer 1

您可以使用 IOUtils .这是代码示例。

@RequestMapping(path = "/getImage/app/path/{filePath}", method = RequestMethod.GET)
public void getImage(HttpServletResponse response, @PathVariable String filePath) throws IOException {
    File file = new File(filePath);
    if(file.exists()) {
        String contentType = "application/octet-stream";
        response.setContentType(contentType);
        OutputStream out = response.getOutputStream();
        FileInputStream in = new FileInputStream(file);
        // copy from in to out
        IOUtils.copy(in, out);
        out.close();
        in.close();
    }else {
        throw new FileNotFoundException();
    }
}