private String url;

public HttpData(String urlHttpGetDataListener listener){

this.url = url;

this.listener = listener;

}

@Override

protected String doInBackground(String... params) {

try {

mHttpClient = new DefaultHttpClient();

mHttpGet = new HttpGet(url);      //这里debug发现HttpGet不到数据，null

mHttpResponse = mHttpClient.execute(mHttpGet); //debug到这就catchException

mHttpEntity = mHttpResponse.getEntity();

in = mHttpEntity.getContent();

BufferedReader br = new BufferedReader(new InputStreamReader(in));

//接下来真正获取数据，先定义一个String

String line = null;

StringBuffer sb = new StringBuffer();

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

sb.append(line);

}

return sb.toString(); //记得去Manifest获取权限

} catch (Exception e) {

}

return "yes";      //之前这里是返回null，报空指针

}