我正在设计一个服务类来定期将数据更新到服务器中。一切正常，但我必须以“MM / dd / yyyy HH：mm：ss”格式将当前的UTC日期时间发送到服务器。我已经尝试了很多方法来实现这一目标，但他们没有给我预期的结果。
班级的源代码：
public class MyAlarmService extends Service {
String device_id;
// GPSTracker class
GPSTracker gps;
String date_time;
@Override
public void onCreate() {
// TODO Auto-generated method stub
//Toast.makeText(this, "Service created", Toast.LENGTH_LONG).show();
//---get a Record---
}
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
//Toast.makeText(this, "MyAlarmService.onBind()", Toast.LENGTH_LONG).show();
return null;
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
//Toast.makeText(this, "Service Destroyed.", Toast.LENGTH_LONG).show();
}
@Override
public void onStart(Intent intent, int startId) {
// TODO Auto-generated method stub
super.onStart(intent, startId);
//Toast.makeText(this, "Service Started.", Toast.LENGTH_LONG).show();
//create class object
gps = new GPSTracker(this);
// check if GPS enabled
if(gps.canGetLocation())
{
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
String locationUsing = gps.getLocationUsing();
final TelephonyManager tm =(TelephonyManager)getBaseContext().getSystemService(Context.TELEPHONY_SERVICE);
String deviceid = tm.getDeviceId();
// Calendar aGMTCalendar = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
// aGMTCalendar.getTimeInMillis(); //or getTimeInMillis()
**Date d = new Date(year);
CharSequence s = DateFormat.format("yyyy-MM-dd hh:mm:ss", d.getTime());**
// get_date();
**SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyy-MM-dd");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
java.util.Date date = null;
System.out.println(dateFormatGmt.format(date));
Toast.makeText(getApplicationContext(),""+date, Toast.LENGTH_LONG).show();**
//Toast.makeText(getApplicationContext(),"Device ID: "+deviceid+ " Time: "+ s+"\nLat: " + latitude + "\nLong: " + longitude, Toast.LENGTH_LONG).show();
Log.w( "\nLat: " , ""+latitude);
Log.w( "\nLong: " , ""+longitude);
if(haveNetworkConnection())
{
// sendPostRequest(deviceid,date_time,""+latitude,""+longitude);
// ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(3);
//
// nameValuePairs.add(new BasicNameValuePair("lat",""+latitude));
// nameValuePairs.add(new BasicNameValuePair("lng",""+longitude));
//
//
// try
// {
// HttpClient httpclient = new DefaultHttpClient();
// //HttpPost httppost = new HttpPost("http://eatcastle.com/security_system_portal/api/getting_lat_lng.php");
// HttpPost httppost = new HttpPost("http://google.com");
// httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// HttpResponse response = httpclient.execute(httppost);
// String responseBody = EntityUtils.toString(response.getEntity());
//
// //Toast.makeText( getApplicationContext(),""+responseBody,Toast.LENGTH_LONG).show();
// }
// catch (Throwable t)
// {
// Log.d("Error",""+t);
// }
}
else
{
Toast.makeText( getApplicationContext(),"No Internet connection or Wifi available",Toast.LENGTH_LONG).show();
}
}
else
{
// GPS or Network is not enabled
Toast.makeText(getApplicationContext(), "No Network no GPS", Toast.LENGTH_LONG).show();
}
}
@Override
public boolean onUnbind(Intent intent) {
// TODO Auto-generated method stub
// Toast.makeText(this, "Service binded", Toast.LENGTH_LONG).show();
return super.onUnbind(intent);
}
//=======================================================================================================
//check packet data and wifi
//=======================================================================================================
private boolean haveNetworkConnection()
{
boolean haveConnectedWifi = false;
boolean haveConnectedMobile = false;
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo[] netInfo = cm.getAllNetworkInfo();
for (NetworkInfo ni : netInfo)
{
if (ni.getTypeName().equalsIgnoreCase("WIFI"))
if (ni.isConnected())
haveConnectedWifi = true;
if (ni.getTypeName().equalsIgnoreCase("MOBILE"))
if (ni.isConnected())
haveConnectedMobile = true;
}
return haveConnectedWifi || haveConnectedMobile;
}
//=======================================================================================================
//checking packet data and wifi END
//=======================================================================================================
void get_date()
{
}
//sending async post request
private void sendPostRequest(String deviceid, String date_time,String latitude, String longitude) {
class SendPostReqAsyncTask extends AsyncTask<String, Void, String>{
@Override
protected String doInBackground(String... params) {
String paramDeviceid = params[0];
String paramDate_time = params[1];
String paramLatitude = params[2];
String paramLongitude = params[3];
//System.out.println("*** doInBackground ** paramUsername " + paramUsername + " paramPassword :" + paramPassword);
HttpClient httpClient = new DefaultHttpClient();
// In a POST request, we don't pass the values in the URL.
//Therefore we use only the web page URL as the parameter of the HttpPost argument
HttpPost httpPost = new HttpPost("http://google.com");
// Because we are not passing values over the URL, we should have a mechanism to pass the values that can be
//uniquely separate by the other end.
//To achieve that we use BasicNameValuePair
//Things we need to pass with the POST request
BasicNameValuePair DeviceidBasicNameValuePair = new BasicNameValuePair("stringLoginUser", paramDeviceid);
BasicNameValuePair Date_timeBasicNameValuePAir = new BasicNameValuePair("stringLoginPwd", paramDate_time);
BasicNameValuePair LatitudeBasicNameValuePAir = new BasicNameValuePair("stringLoginPwd", paramLatitude);
BasicNameValuePair LongitudeBasicNameValuePAir = new BasicNameValuePair("stringLoginPwd", paramLongitude);
// We add the content that we want to pass with the POST request to as name-value pairs
//Now we put those sending details to an ArrayList with type safe of NameValuePair
List<NameValuePair> nameValuePairList = new ArrayList<NameValuePair>();
nameValuePairList.add(DeviceidBasicNameValuePair);
nameValuePairList.add(Date_timeBasicNameValuePAir);
nameValuePairList.add(LatitudeBasicNameValuePAir);
nameValuePairList.add(LongitudeBasicNameValuePAir);
try {
// UrlEncodedFormEntity is an entity composed of a list of url-encoded pairs.
//This is typically useful while sending an HTTP POST request.
UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(nameValuePairList);
// setEntity() hands the entity (here it is urlEncodedFormEntity) to the request.
httpPost.setEntity(urlEncodedFormEntity);
try {
// HttpResponse is an interface just like HttpPost.
//Therefore we can't initialize them
HttpResponse httpResponse = httpClient.execute(httpPost);
// According to the JAVA API, InputStream constructor do nothing.
//So we can't initialize InputStream although it is not an interface
InputStream inputStream = httpResponse.getEntity().getContent();
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
StringBuilder stringBuilder = new StringBuilder();
String bufferedStrChunk = null;
while((bufferedStrChunk = bufferedReader.readLine()) != null){
stringBuilder.append(bufferedStrChunk);
}
return stringBuilder.toString();
} catch (ClientProtocolException cpe) {
System.out.println("First Exception caz of HttpResponese :" + cpe);
cpe.printStackTrace();
} catch (IOException ioe) {
System.out.println("Second Exception caz of HttpResponse :" + ioe);
ioe.printStackTrace();
}
} catch (UnsupportedEncodingException uee) {
System.out.println("An Exception given because of UrlEncodedFormEntity argument :" + uee);
uee.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
Toast.makeText(getApplicationContext(), result, Toast.LENGTH_LONG).show();
}
}
SendPostReqAsyncTask sendPostReqAsyncTask = new SendPostReqAsyncTask();
sendPostReqAsyncTask.execute(deviceid, date_time,latitude,longitude);
}
}
我应该如何以上述格式获取当前的utc日期时间并将其发送到服务器？
P.S。：有时在实现不同的方法时，我还发现了一个IDE错误，说明没有定义新的Date（）构造函数。
答案 0 :(得分：3)
您可以使用System.currentTimeMillis()，这将从1970年1月1日00:00:00 UTC开始返回很长的毫秒数。您可以使用日期格式在任何时区将日期转换为字符串：
DateFormat df = DateFormat.getTimeInstance();
df.setTimeZone(TimeZone.getTimeZone("gmt"));
String gmtTime = df.format(new Date());
答案 1 :(得分：1)
为什么要将 null 分配给日期值？？
检查出来：
Date formattedDate = new Date(System.currentTimeMillis());
SimpleDateFormat sdf = new SimpleDateFormat("yyyy MM dd, hh:mm a", Locale.US);
String time = sdf.format(formattedDate);