Android 4.0 HttpUrlConnection的getInputStream()方法总是返回空的问题

Java代码


public String downTxt(String urlStr) {

StringBuffer sBuffer = new StringBuffer();

String line = null;

BufferedReader bReader = null;

try {

URL url = new URL(urlStr);

HttpURLConnection conn = (HttpURLConnection) url.openConnection();

bReader = new BufferedReader(new InputStreamReader(

conn.getInputStream()));

while ((line = bReader.readLine()) != null) {

sBuffer.append(line);

}

} catch (MalformedURLException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

} finally {

try {

bReader.close();

} catch (IOException e) {

e.printStackTrace();

}

}

return sBuffer.toString();

}

走到

Java代码


bReader = new BufferedReader(new InputStreamReader(

conn.getInputStream()));

就会报空指针错误。为什么呢 ？

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<uses-sdk android:minSdkVersion="14"/> 改为 14以下版本。。。就OK。。。不行的话呢 再试试其他的sdk版本，总之就是这个地方的问题

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经测试，7，8，9三个版本是可以的，同时，去掉android:targetSdkVersion