我以前使用HttpClient和BasicNameValuePairs,由于某种原因我必须转移到HttpUrlConnection.
因此这个代码,使一个HttpPost请求具有一些参数：
public class MConnections {
static String BaseURL = "http://www.xxxxxxxxx.com";
static String charset = "UTF-8";
private static String result;
private static StringBuilder sb;
private static List<String> cookies = new ArrayList<String>();
public static String PostData(String url,String sa[][]) {
HttpURLConnection connection = null;
try {
connection = (HttpURLConnection) new URL(BaseURL + url)
.openConnection();
} catch (MalformedURLException e1) {
} catch (IOException e1) {
}
cookies = connection.getHeaderFields().get("Set-Cookie");
try{
connection.setDoOutput(true); // Triggers POST.
connection.setRequestProperty("Accept-Charset",charset);
connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded;charset=" + charset);
}catch (Exception e) {
//Here i get Exception that "java.lang.IllegalStateException: Already connected"
}
OutputStream output = null;
String query = "";
int n = sa.length;
for (int i = 0; i < n; i++) {
try {
query = query + sa[i][0] + "="
+ URLEncoder.encode(sa[i][1],"UTF-8");
} catch (UnsupportedEncodingException e) {
}
}
try {
output = connection.getOutputStream();
output.write(query.getBytes(charset));
} catch (Exception e) {
//Here i get Exception that "android: java.net.protocolException: Does not support output"
} finally {
if (output != null)
try {
output.close();
} catch (IOException e) {
}
}
InputStream response = null;
try {
response = connection.getInputStream();
} catch (IOException e) {
//Here i get Exception that "java.io.IOException: BufferedInputStream is closed"
} finally {
//But i am closing it here
connection.disconnect();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
response,"iso-8859-1"),8);
sb = new StringBuilder();
sb.append(reader.readLine());
String line = "0";
while ((line = reader.readLine()) != null) {
sb.append("\n" + line);
}
response.close();
result = sb.toString();
} catch (Exception e) {
}
return result;
}
}@H_502_5@
但是我在代码中注释了这样的异常.
其实我正在使用AsyncTask从我的Activity中调用MConnections.PostData()两次.这可能会导致异常：已连接,但我正在使用connection.disconnect.但为什么我还会得到这个异常？
我用错了吗？
谢谢
解决方法
对于协议异常,请在调用getOutputStream()之前尝试添加以下内容：
connection.setDoOutput(true);@H_502_5@发现这个答案感谢Brian Roach在这里的答复：https://stackoverflow.com/a/14026377/387781
旁注：我在运行Gingerbread的HTC Thunderbolt上出现了这个问题,但不是在运行Jelly Bean的Nexus 4上.
