java - 在 Java 中以 Base64 编码来自 URL 的图像

Question

我想使用 Base64 对 URL 图像进行编码和保存。我发现了几个从本地文件而不是从 URL 进行编码的示例。有没有可能这样做？

我试过类似的东西，但没有成功。任何线索，帮助？感谢您的回答。

    public static void main(String[] args)  {
    String imageUrl = "http://www.avajava.com/images/avajavalogo.jpg";
    String destinationFile = "image.jpg";

    try {           
        // Reading a Image file from file system
        URL url = new URL(imageUrl);
        InputStream is = url.openStream();

        FileInputStream imageInFile = new FileInputStream(is.toString());
        byte imageData[] = new byte[2048];
        imageInFile.read(imageData);

        // Converting Image byte array into Base64 String
        String imageDataString = encodeImage(imageData);
        System.out.println("imageDataString : " + imageDataString);




        System.out.println("Image Successfully Manipulated!");
    } catch (FileNotFoundException e) {
        System.out.println("Image not found" + e);
    } catch (IOException ioe) {
        System.out.println("Exception while reading the Image " + ioe);
    }

}

/**
 * Encodes the byte array into base64 string
 *
 * @param imageByteArray - byte array
 * @return String a {@link java.lang.String}
 */
public static String encodeImage(byte[] imageByteArray) {
    return Base64.encodeBase64URLSafeString(imageByteArray);
}

Answer 1

通过在参数中传递图像 url 来尝试此功能。

private String getByteArrayFromImageURL(String url) {

    try {
        URL imageUrl = new URL(url);
        URLConnection ucon = imageUrl.openConnection();
        InputStream is = ucon.getInputStream();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int read = 0;
        while ((read = is.read(buffer, 0, buffer.length)) != -1) {
            baos.write(buffer, 0, read);
        }
        baos.flush();
        return Base64.encodeToString(baos.toByteArray(), Base64.DEFAULT);
    } catch (Exception e) {
        Log.d("Error", e.toString());
    }
    return null;
}