URL - Android 中图像文件的 FileNotFoundException答案

【问题标题】：URL - FileNotFoundException for image file in AndroidURL - Android 中图像文件的 FileNotFoundException
【发布时间】：2012-03-13 10:59:19
【问题描述】：

我正在尝试从特定 URL 获取图像，但它会抛出FileNotFoundException。如果我尝试从浏览器打开网址，我可以看到图像。请帮忙。下面是我的代码。谢谢。

String fileURL = "http://sposter.smartag.my/images/KFC_Voucher.jpg";
String FILENAME = "caldophilus.jpg";
URL u = new URL(fileURL);
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
File root = Environment.getExternalStorageDirectory();
FileOutputStream f = new FileOutputStream(new File(root, FILENAME));
InputStream x=c.getInputStream();
int size=x.available();
byte b[]= new byte[size];
x.read(b);
f.write(b);
f.flush();
f.close();

【问题讨论】：

您昨天发布了同样的问题。你还没有得到正确的答案吗？
昨天我使用网络服务来检索图像，现在我使用 URL...
@chinna_82 我在浏览器中打开了您的网址，它显示 404 - 找不到文件或目录。
@Padma Kumar 请立即查看。我更改了图片网址。请检查新网址
stackoverflow.com/questions/5886965/…

标签： java android exception

【解决方案1】：

在...

FileOutputStream f = new FileOutputStream(new File(root, FILENAME));

尝试将 FILENAME 替换为 fileURL。另外，在哪一行抛出异常？这会有所帮助。

【讨论】：

我正在从 Galaxy Nexus 进行测试，我无法找到导致错误的行......如果我将 FILENAME 更改为 fileUrl 我得到 /mnt/sdcard/sposter.smartag.my/images/caldophilus.jpg:open failed:ENOENT(no这样的文件或目录）

【解决方案2】：

试试这个：

  BufferedInputStream inputStream = null;
  OutputStream out = null;

  String fileName = null;
  String path = null;
  File savedFile = null;

  try
  {
      // Replace your URL here.
      URL fileURL = new URL("http://enter.your.url.here");
      URLConnection connection = fileURL.openConnection();
      connection.connect();

      inputStream = new java.io.BufferedInputStream(connection.getInputStream());

      // Replace your save path here.
      File fileDir = new File("path/to/save");
      fileDir.mkdirs();
      savedFile = new File("path/to/save", fileName);
      out = new FileOutputStream(savedFile);

      byte buf[] = new byte[1024];
      int len;

      long total = 0;

      while ((len = inputStream.read(buf)) != -1)
      {
        total += len;
        out.write(buf, 0, len);
      }

      out.close();
      inputStream.close();
  }
  catch (Exception)
  {

  }

【讨论】：

【解决方案3】：

试试下面的代码。它应该工作！

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;


public class DownloadManager {

    public static void downLoadImage(String imageURL, String destinationFileName) throws IOException {
        URL url = new URL(imageURL);
        InputStream inputStream = url.openStream();
        OutputStream outputStream = new FileOutputStream(destinationFileName);
        byte[] byteData = new byte[2048];
        int length;
        while((length=inputStream.read(byteData))!=-1) {
            outputStream.write(byteData, 0, length);
        }
        inputStream.close();
        outputStream.close();
    }

    public static void main(String[] args) throws IOException {
        String imageURL = "http://sposter.smartag.my/images/KFC_Voucher.jpg";
        String destinationFileName = "C:/Users/sarath_sivan/Desktop/caldophilus.jpg";
        downLoadImage(imageURL, destinationFileName);
    }
}

【讨论】：

【解决方案4】：

我试试这个，它的工作正常。谢谢。

URL url = new URL(fileURL);
URLConnection conexion = url.openConnection();
conexion.connect();
int lenghtOfFile = conexion.getContentLength();
Log.d("ANDRO_ASYNC", "Lenght of file: " + lenghtOfFile);
InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream("/sdcard/caldophilus.jpg");
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
output.write(data, 0, count);
}
output.flush();
output.close();
input.close();

【讨论】：

【解决方案5】：

立即尝试 -

try {
            url = paths[0];
            HttpURLConnection connection = (HttpURLConnection) url
                    .openConnection();
            int length = connection.getContentLength();
            InputStream is = (InputStream) url.getContent();
            byte[] imageData = new byte[length];
            int buffersize = (int) Math.ceil(length / (double) 100);
            int downloaded = 0;
            int read;
            while (downloaded < length) {
                if (length < buffersize) {
                    read = is.read(imageData, downloaded, length);
                } else if ((length - downloaded) <= buffersize) {
                    read = is.read(imageData, downloaded, length
                            - downloaded);
                } else {
                    read = is.read(imageData, downloaded, buffersize);
                }
                downloaded += read;
                publishProgress((downloaded * 100) / length);
            }
            Bitmap bitmap = BitmapFactory.decodeByteArray(imageData, 0,
                    length);
            if (bitmap != null) {
                Log.i(TAG, "Bitmap created");
            } else {
                Log.i(TAG, "Bitmap not created");
            }
            is.close();
            return bitmap;
        } catch (MalformedURLException e) {
            Log.e(TAG, "Malformed exception: " + e.toString());
        } catch (IOException e) {
            Log.e(TAG, "IOException: " + e.toString());
        } catch (Exception e) {
            Log.e(TAG, "Exception: " + e.toString());
        }

还有，看看here

【讨论】：

【解决方案6】：

String fileURL = "http://sposter.smartag.my/images/KFC_Voucher.jpg";

String FILENAME = "caldophilus.jpg";

URL u = new URL(fileURL);

HttpURLConnection c = (HttpURLConnection) u.openConnection();

c.setRequestMethod("GET");

//c.setDoOutput(true); =========== remove this;

c.connect();

【讨论】：