尝试以下代码使用谷歌时区API从Java与当前NTP时间客户端和正确的UTC_Datetime_from_timestamp转换:

String get_xml_server_reponse(String server_url){

    URL xml_server = null;

    String xmltext = "";

    InputStream input;


    try {
        xml_server = new URL(server_url);


        try {
            input = xml_server.openConnection().getInputStream();


            final BufferedReader reader = new BufferedReader(new InputStreamReader(input));
            final StringBuilder sBuf = new StringBuilder();

            String line = null;
            try {
                while ((line = reader.readLine()) != null) 
                {
                    sBuf.append(line);
                }
               } 
            catch (IOException e) 
              {
                    Log.e(e.getMessage(), "XML parser, stream2string 1");
              } 
            finally {
                try {
                    input.close();
                    }
                catch (IOException e) 
                {
                    Log.e(e.getMessage(), "XML parser, stream2string 2");
                }
            }

            xmltext =  sBuf.toString();

        } catch (IOException e1) {

                e1.printStackTrace();
            }


        } catch (MalformedURLException e1) {

          e1.printStackTrace();
        }

     return  xmltext;

  }     


 private String get_UTC_Datetime_from_timestamp(long timeStamp){

    try{

        Calendar cal = Calendar.getInstance();
        TimeZone tz = cal.getTimeZone();

        int tzt = tz.getOffset(System.currentTimeMillis());

        timeStamp -= tzt;

        // DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",Locale.getDefault());
        DateFormat sdf = new SimpleDateFormat();
        Date netDate = (new Date(timeStamp));
        return sdf.format(netDate);
    }
    catch(Exception ex){
        return "";
     }
    } 

 class NTP_UTC_Time
 {
     private static final String TAG = "SntpClient";

     private static final int RECEIVE_TIME_OFFSET = 32;
     private static final int TRANSMIT_TIME_OFFSET = 40;
     private static final int NTP_PACKET_SIZE = 48;

     private static final int NTP_PORT = 123;
     private static final int NTP_MODE_CLIENT = 3;
     private static final int NTP_VERSION = 3;

     // Number of seconds between Jan 1, 1900 and Jan 1, 1970
     // 70 years plus 17 leap days
     private static final long OFFSET_1900_TO_1970 = ((365L * 70L) + 17L) * 24L * 60L * 60L;

     private long mNtpTime;

     public boolean requestTime(String host, int timeout) {
         try {
             DatagramSocket socket = new DatagramSocket();
             socket.setSoTimeout(timeout);
             InetAddress address = InetAddress.getByName(host);
             byte[] buffer = new byte[NTP_PACKET_SIZE];
             DatagramPacket request = new DatagramPacket(buffer, buffer.length, address, NTP_PORT);

             buffer[0] = NTP_MODE_CLIENT | (NTP_VERSION << 3);

             writeTimeStamp(buffer, TRANSMIT_TIME_OFFSET);

             socket.send(request);

             // read the response
             DatagramPacket response = new DatagramPacket(buffer, buffer.length);
             socket.receive(response);          
             socket.close();

             mNtpTime = readTimeStamp(buffer, RECEIVE_TIME_OFFSET);            
         } catch (Exception e) {
           //  if (Config.LOGD) Log.d(TAG, "request time failed: " + e);
             return false;
         }

         return true;
     }


     public long getNtpTime() {
         return mNtpTime;
     }


     /**
      * Reads an unsigned 32 bit big endian number from the given offset in the buffer.
      */
     private long read32(byte[] buffer, int offset) {
         byte b0 = buffer[offset];
         byte b1 = buffer[offset+1];
         byte b2 = buffer[offset+2];
         byte b3 = buffer[offset+3];

         // convert signed bytes to unsigned values
         int i0 = ((b0 & 0x80) == 0x80 ? (b0 & 0x7F) + 0x80 : b0);
         int i1 = ((b1 & 0x80) == 0x80 ? (b1 & 0x7F) + 0x80 : b1);
         int i2 = ((b2 & 0x80) == 0x80 ? (b2 & 0x7F) + 0x80 : b2);
         int i3 = ((b3 & 0x80) == 0x80 ? (b3 & 0x7F) + 0x80 : b3);

         return ((long)i0 << 24) + ((long)i1 << 16) + ((long)i2 << 8) + (long)i3;
     }

     /**
      * Reads the NTP time stamp at the given offset in the buffer and returns 
      * it as a system time (milliseconds since January 1, 1970).
      */    
     private long readTimeStamp(byte[] buffer, int offset) {
         long seconds = read32(buffer, offset);
         long fraction = read32(buffer, offset + 4);
         return ((seconds - OFFSET_1900_TO_1970) * 1000) + ((fraction * 1000L) / 0x100000000L);        
     }

     /**
      * Writes 0 as NTP starttime stamp in the buffer. --> Then NTP returns Time OFFSET since 1900
      */    
     private void writeTimeStamp(byte[] buffer, int offset) {        
         int ofs =  offset++;

         for (int i=ofs;i<(ofs+8);i++)
           buffer[i] = (byte)(0);             
     }

 }

 String get_time_zone_time(GeoPoint gp){

        String erg = "";
        String raw_offset = "";
        String dst_offset = "";

        double Longitude = gp.getLongitudeE6()/1E6;
        double Latitude = gp.getLatitudeE6()/1E6;



        long tsLong = 0; // System.currentTimeMillis()/1000;

        NTP_UTC_Time client = new NTP_UTC_Time();

        if (client.requestTime("pool.ntp.org", 2000)) {              
          tsLong = client.getNtpTime();
        }

        if (tsLong != 0)
        {

        tsLong = tsLong  / 1000;

        // https://maps.googleapis.com/maps/api/timezone/xml?location=39.6034810,-119.6822510&timestamp=1331161200&sensor=false

        String request = "https://maps.googleapis.com/maps/api/timezone/xml?location="+Latitude+","+ Longitude+ "&timestamp="+tsLong +"&sensor=false";

        String xmltext = get_xml_server_reponse(request);

        if(xmltext.compareTo("")!= 0)
        {

         int startpos = xmltext.indexOf("<TimeZoneResponse");
         xmltext = xmltext.substring(startpos);



        XmlPullParser parser;
        try {
            parser = XmlPullParserFactory.newInstance().newPullParser();


             parser.setInput(new StringReader (xmltext));

             int eventType = parser.getEventType();  

             String tagName = "";


             while(eventType != XmlPullParser.END_DOCUMENT) {
                 switch(eventType) {

                     case XmlPullParser.START_TAG:

                           tagName = parser.getName();

                         break;


                     case XmlPullParser.TEXT :


                        if  (tagName.equalsIgnoreCase("raw_offset"))
                          if(raw_offset.compareTo("")== 0)                               
                            raw_offset = parser.getText();  

                        if  (tagName.equalsIgnoreCase("dst_offset"))
                          if(dst_offset.compareTo("")== 0)
                            dst_offset = parser.getText();  


                        break;   

                 }

                 try {
                        eventType = parser.next();
                    } catch (IOException e) {

                        e.printStackTrace();
                    }

                }

                } catch (XmlPullParserException e) {

                    e.printStackTrace();
                    erg += e.toString();
                }

        }      

        int ro = 0;
        if(raw_offset.compareTo("")!= 0)
        { 
            float rof = str_to_float(raw_offset);
            ro = (int)rof;
        }

        int dof = 0;
        if(dst_offset.compareTo("")!= 0)
        { 
            float doff = str_to_float(dst_offset);
            dof = (int)doff;
        }

        tsLong = (tsLong + ro + dof) * 1000;



        erg = get_UTC_Datetime_from_timestamp(tsLong);
        }


  return erg;

}

并将其用于:

GeoPoint gp = new GeoPoint(39.6034810,-119.6822510);
String Current_TimeZone_Time = get_time_zone_time(gp);

通过使用纬度和经度得到当前位置下面的时区代码为我工作

String data = null;         
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
Location ll = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
double lat = 0,lng = 0;
if(ll!=null){
    lat=ll.getLatitude();
    lng=ll.getLongitude();
}
System.out.println(" Last known location of device  == "+lat+"    "+lng);

InputStream iStream = null; 
HttpURLConnection urlConnection = null;
try{
    timezoneurl = timezoneurl+"location=22.7260783,75.8781553&timestamp=1331161200";                    
    // timezoneurl = timezoneurl+"location="+lat+","+lng+"&timestamp=1331161200";

    URL url = new URL(timezoneurl);                
    // Creating an http connection to communicate with url 
    urlConnection = (HttpURLConnection) url.openConnection(); 

    // Connecting to url 
    urlConnection.connect();                

    // Reading data from url 
    iStream = urlConnection.getInputStream();

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

    StringBuffer sb  = new StringBuffer();
    String line = "";
    while( ( line = br.readLine())  != null){
        sb.append(line);
    }
    data = sb.toString();
    br.close();

}catch(Exception e){
    Log.d("Exception while downloading url", e.toString());
}finally{
    try {
        iStream.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    urlConnection.disconnect();
}

try {
    if(data!=null){
        JSONObject jobj=new JSONObject(data);
        timezoneId = jobj.getString("timeZoneId");

        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
        format.setTimeZone(TimeZone.getTimeZone(timezoneId));

        Calendar cl = Calendar.getInstance(TimeZone.getTimeZone(timezoneId));
        System.out.println("time zone id in android ==  "+timezoneId);

        System.out.println("time zone of  device in android == "+TimeZone.getTimeZone(timezoneId));
        System.out.println("time fo device in android "+cl.getTime());
    }
} catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

https://en.wikipedia.org/wiki/Great-circle_distance

下面是一个使用JSON数据的很好的实现: https://github.com/agap/llttz

public TimeZone nearestTimeZone(Location node) {
    double bestDistance = Double.MAX_VALUE;
    Location bestGuess = timeZones.get(0);

    for (Location current : timeZones.subList(1, timeZones.size())) {
        double newDistance = distanceInKilometers(node, current);

        if (newDistance < bestDistance) {
            bestDistance = newDistance;
            bestGuess = current;
        }
    }

    return java.util.TimeZone.getTimeZone(bestGuess.getZone());
}

  protected double distanceInKilometers(final double latFrom, final double lonFrom, final double latTo, final double lonTo) {
        final double meridianLength = 111.1;
        return meridianLength * centralAngle(latFrom, lonFrom, latTo, lonTo);
    }

    protected double centralAngle(final Location from, final Location to) {
        return centralAngle(from.getLatitude(), from.getLongitude(), to.getLatitude(), to.getLongitude());
    }

    protected double centralAngle(final double latFrom, final double lonFrom, final double latTo, final double lonTo) {
        final double latFromRad = toRadians(latFrom),
                lonFromRad = toRadians(lonFrom),
                latToRad   = toRadians(latTo),
                lonToRad   = toRadians(lonTo);

        final double centralAngle = toDegrees(acos(sin(latFromRad) * sin(latToRad) + cos(latFromRad) * cos(latToRad) * cos(lonToRad - lonFromRad)));

        return centralAngle <= 180.0 ? centralAngle : (360.0 - centralAngle);
    }

    protected double distanceInKilometers(final Location from, final Location to) {
        return distanceInKilometers(from.getLatitude(), from.getLongitude(), to.getLatitude(), to.getLongitude());
    }
}

对于我们这些使用Javascript并希望通过谷歌api从邮政编码获取时区的人来说，这里有一个方法。

通过地理定位获取lat/lng 通过这个参数获取时区 进入时区API。 此处使用Luxon进行时区转换。

注意:我的理解是，邮政编码在不同的国家并不是唯一的，所以这可能最适合在美国使用。

const googleMapsClient; // instantiate your client here
const zipcode = '90210'
const myDateThatNeedsTZAdjustment; // define your date that needs adjusting
// fetch lat/lng from google api by zipcode
const geocodeResponse = await googleMapsClient.geocode({ address: zipcode }).asPromise();
if (geocodeResponse.json.status === 'OK') {
  lat = geocodeResponse.json.results[0].geometry.location.lat;
  lng = geocodeResponse.json.results[0].geometry.location.lng;
} else {
  console.log('Geocode was not successful for the following reason: ' + status);
}

// prepare lat/lng and timestamp of profile created_at to fetch time zone
const location = `${lat},${lng}`;
const timestamp = new Date().valueOf() / 1000;
const timezoneResponse = await googleMapsClient
  .timezone({ location: location, timestamp: timestamp })
  .asPromise();

const timeZoneId = timezoneResponse.json.timeZoneId;
// adjust by setting timezone
const timezoneAdjustedDate = DateTime.fromJSDate(
  myDateThatNeedsTZAdjustment
).setZone(timeZoneId);

我写了一个包https://github.com/ringsaturn/tzf支持获取时区在Go&Python和非常快:

package main

import (
    "fmt"

    "github.com/ringsaturn/tzf"
)

func main() {
    finder, err := tzf.NewDefaultFinder()
    if err != nil {
        panic(err)
    }
    fmt.Println(finder.GetTimezoneName(116.6386, 40.0786))
}

Python https://github.com/ringsaturn/tzfpy sample:

from tzfpy import get_tz

print(get_tz(121.4737, 31.2305))

Rust https://github.com/ringsaturn/tzf-rs样品:

use tzf_rs::DefaultFinder;

fn main() {
    let finder = DefaultFinder::new();

    print!("{:?}\n", DefaultFinder.get_tz_name(116.3883, 39.9289));
}

There are several sources online that have geojson data for timezones (here's one, here's another) Use a geometry library to create polygon objects from the geojson coordinates (shapely [python], GEOS [c++], JTS [java], NTS [.net]). Convert your lat/lng to a point object (however your library represents that) and check if it intersects the timezone polygon. from shapely.geometry import Polygon, Point def get_tz_from_lat_lng(lat, lng): for tz, geojson in timezones.iteritems(): coordinates = geojson['features'][0]['geometry']['coordinates'] polygon = Polygon(coordinates) point = Point(lng, lat) if polygon.contains(point): return tz