正在检索给定未知主机异常的位图？

Question

我正在使用这段代码从web获取位图。

  try {
        Bitmap bitmap=null;
        URL imageUrl = new URL(url);
        HttpURLConnection conn = (HttpURLConnection)imageUrl.openConnection();
        conn.setConnectTimeout(30000);
        conn.setReadTimeout(30000);
        InputStream is=conn.getInputStream(); ///Error is pointing me here
        OutputStream os = new FileOutputStream(f);
        Utils.CopyStream(is, os);
        os.close();
        bitmap = decodeFile(f);
        return bitmap;
    } catch (Exception ex){
       ex.printStackTrace();
       return null;
    }

唯一的问题是我一直收到这个错误。每次我都会尝试获取位图。这个错误告诉我：

 InputStream is=conn.getInputStream();


09-30 06:54:32.512: WARN/System.err(11149):     at java.net.InetAddress.lookupHostByName(InetAddress.java:497)
09-30 06:54:32.512: WARN/System.err(11149):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:294)
09-30 06:54:32.512: WARN/System.err(11149):     at java.net.InetAddress.getAllByName(InetAddress.java:256)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>(HttpConnection.java:69)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>(HttpConnection.java:48)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection$Address.connect(HttpConnection.java:322)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnectionPool.get(HttpConnectionPool.java:89)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getHttpConnection(HttpURLConnectionImpl.java:285)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.makeConnection(HttpURLConnectionImpl.java:267)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.retrieveResponse(HttpURLConnectionImpl.java:1018)
09-30 06:54:32.512: WARN/System.err(11149):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:512)

Answer 1

显然，您的url地址无效。将您的url手动复制到浏览器窗口中，您应该会看到相同的错误。

Answer 2

这是网络错误，可能是您没有添加internet权限，或者您的连接网络设置不正确，或者您的url错误.................