进行坐标系转换，主要是WGS84(大地坐标系，如谷歌地图)、GCJ02(国测局坐标系，如高德地图)、BD09(百度坐标系)三种主流坐标系之间的转换。
当然，如高德地图、百度地图都提供了在线的坐标转换服务，如百度的参见：/index.php?title=webapi/guide/changeposition。
具体转换工具类Java代码如下：
/*** * 坐标系转换工具类*/public class GPSUtil {public static double pi = 3.1415926535897932384626;public static double x_pi = 3.14159265358979324 * 3000.0 / 180.0;public static double a = 6378245.0;public static double ee = 0.00669342162296594323;public static double transformLat(double x, double y) {double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y+ 0.2 * Math.sqrt(Math.abs(x));ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;ret += (160.0 * Math.sin(y / 12.0 * pi) + 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;return ret;}public static double transformLon(double x, double y) {double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1* Math.sqrt(Math.abs(x));ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0* pi)) * 2.0 / 3.0;return ret;}public static double[] transform(double lat, double lon) {if (outOfChina(lat, lon)) {return new double[] {lat, lon };}double dLat = transformLat(lon - 105.0, lat - 35.0);double dLon = transformLon(lon - 105.0, lat - 35.0);double radLat = lat / 180.0 * pi;double magic = Math.sin(radLat);magic = 1 - ee * magic * magic;double sqrtMagic = Math.sqrt(magic);dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);double mgLat = lat + dLat;double mgLon = lon + dLon;return new double[] {mgLat, mgLon };}public static boolean outOfChina(double lat, double lon) {if (lon < 72.004 || lon > 137.8347)return true;if (lat < 0.8293 || lat > 55.8271)return true;return false;}/*** 84 to 火星坐标系 (GCJ-02) World Geodetic System ==> Mars Geodetic System* * @param lat* @param lon* @return*/public static double[] gps84_To_Gcj02(double lat, double lon) {if (outOfChina(lat, lon)) {return new double[] {lat, lon };}double dLat = transformLat(lon - 105.0, lat - 35.0);double dLon = transformLon(lon - 105.0, lat - 35.0);double radLat = lat / 180.0 * pi;double magic = Math.sin(radLat);magic = 1 - ee * magic * magic;double sqrtMagic = Math.sqrt(magic);dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);double mgLat = lat + dLat;double mgLon = lon + dLon;return new double[] {mgLat, mgLon };}/*** * 火星坐标系 (GCJ-02) to 84 * * @param lon * @param lat * @return* */public static double[] gcj02_To_Gps84(double lat, double lon) {double[] gps = transform(lat, lon);double lontitude = lon * 2 - gps[1];double latitude = lat * 2 - gps[0];return new double[] {latitude, lontitude };}/*** 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 将 GCJ-02 坐标转换成 BD-09 坐标* * @param lat* @param lon*/public static double[] gcj02_To_Bd09(double lat, double lon) {double x = lon, y = lat;double z = Math.sqrt(x * x + y * y) + 0.00002 * Math.sin(y * x_pi);double theta = Math.atan2(y, x) + 0.000003 * Math.cos(x * x_pi);double tempLon = z * Math.cos(theta) + 0.0065;double tempLat = z * Math.sin(theta) + 0.006;double[] gps = {tempLat, tempLon };return gps;}/*** * 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 * * 将 BD-09 坐标转换成GCJ-02 坐标 * * @param* bd_lat * @param bd_lon * @return*/public static double[] bd09_To_Gcj02(double lat, double lon) {double x = lon - 0.0065, y = lat - 0.006;double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * x_pi);double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * x_pi);double tempLon = z * Math.cos(theta);double tempLat = z * Math.sin(theta);double[] gps = {tempLat, tempLon };return gps;}/*** 将gps84转为bd09* * @param lat* @param lon* @return*/public static double[] gps84_To_bd09(double lat, double lon) {double[] gcj02 = gps84_To_Gcj02(lat, lon);double[] bd09 = gcj02_To_Bd09(gcj02[0], gcj02[1]);return bd09;}public static double[] bd09_To_gps84(double lat, double lon) {double[] gcj02 = bd09_To_Gcj02(lat, lon);double[] gps84 = gcj02_To_Gps84(gcj02[0], gcj02[1]);// 保留小数点后六位gps84[0] = retain6(gps84[0]);gps84[1] = retain6(gps84[1]);return gps84;}/*** 保留小数点后六位* * @param num* @return*/private static double retain6(double num) {String result = String.format("%.6f", num);return Double.valueOf(result);}public static void main(String[] args) {String str = "113.2362898,21.9053547;113.2353993,21.9076491;113.2352312,21.9079071;113.2345464,21.9086146;113.2342782,21.9089879;113.2341989,21.9093424;113.2342173,21.9101219;113.2345064,21.9118989";String[] arr = str.split(";");String res = "";for(String s : arr) {String[] lntlat = s.split(",");Double lnt = Double.parseDouble(lntlat[0]);Double lat = Double.parseDouble(lntlat[1]);double[] bd09 = gps84_To_bd09(lnt, lat);res += bd09[0] + "," + bd09[1] + ";";}res = res.substring(0, res.lastIndexOf(";"));System.out.println(res);}}
