java - 网址格式错误异常

Question

我收到格式错误的网址异常 http://staging.squadrun.co/media/question_images/2013_Map_Vector_3.jpg

URL url = new URL(src);
HttpURLConnection ucon = (HttpURLConnection) url.openConnection();
ucon.setInstanceFollowRedirects(false);
URL secondUrl = new URL(ucon.getHeaderField("Location"));


HttpURLConnection connection = (HttpURLConnection) secondUrl.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
} catch (IOException e){
    Log.d("sg", "src" + src );
    e.printStackTrace();
    return null;
}

Answer 1

您在这一行中得到一个 NullpointerException:

URL secondUrl = new URL(ucon.getHeaderField("Location"));

因为ucon.getHeaderField("Location")返回null并且这些NullpointerException被映射到MalformedURLException。

Exception in thread "main" java.net.MalformedURLException
    at java.net.URL.<init>(Unknown Source)
    at java.net.URL.<init>(Unknown Source)
    at java.net.URL.<init>(Unknown Source)
    at Test.main(Test.java:16)
Caused by: java.lang.NullPointerException
    ... 4 more