android 中转换不同坐标系

在做项目时用到了谷歌定位 ， 需要把坐标系传入服务器在百度地图上面显示实时位置，

但是谷歌定位的坐标系和百度地图的坐标系有偏差 ，根据以下方法就可以进行互转。

package com.xiansen.eremis.util;

import java.text.DecimalFormat;

public class GPSUtil {

public static double pi = 3.1415926535897932384626;
public static double x_pi = 3.14159265358979324 * 3000 / 180;
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
 */
private static final String TAG = "GPSUtil";

public static double[] gps84_To_Gcj02(double lat, double lon) {
    if (outOfChina(lat, lon)) {
        return null;
    }
    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
 * 将设备定位坐标转换成百度地图的坐标
 * @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]);
    DecimalFormat df = new DecimalFormat("0.000000");
    double latitude = Double.valueOf(df.format(bd09[0]));
    double longitude = Double.valueOf(df.format(bd09[1]));
    double[] bd09s = {latitude, longitude};
    return bd09s;
}

/**
 * 将bd09转为bd09
 *
 * @param lat
 * @param lon
 * @return
 */
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]);
    return gps84;
}
           

}

上面的代码如果不懂可以留言咨询，谢谢。