Android开发之火星坐标转换工具

代码：

 import java.io.InputStream;
 import java.io.ObjectInputStream;

 /*
  * 把获取到的真实地址转换为火星坐标
  */
 public class LocationUtils {

     public static double[] standardToChina(Double x, Double y) {

         try {
             double[] haha = new double[2];
             PointDouble pointDouble = new PointDouble(x, y);
             PointDouble s2c = ModifyOffset.getInstance(
                     ModifyOffset.class.getResourceAsStream("axisoffset.dat"))
                     .s2c(pointDouble);
             haha[0] = s2c.x;
             haha[1] = s2c.y;
             return haha;
         } catch ( Exception e ) {
             e.printStackTrace();
         }

         return null;

     }

     static class ModifyOffset {
         private static ModifyOffset modifyOffset;
         static double[] X = new double[660 * 450];
         static double[] Y = new double[660 * 450];

         private ModifyOffset(InputStream inputStream) throws Exception {
             init(inputStream);
         }

         public synchronized static ModifyOffset getInstance(InputStream is)
                 throws Exception {
             if ( modifyOffset == null ) {
                 modifyOffset = new ModifyOffset(is);
             }
             return modifyOffset;
         }

         public void init(InputStream inputStream) throws Exception {
             ObjectInputStream in = new ObjectInputStream(inputStream);
             try {
                 int i = 0;
                 while ( in.available() > 0 ) {
                     if ( (i & 1) == 1 ) {
                         Y[(i - 1) >> 1] = in.readInt() / 100000.0d;
                         ;
                     } else {
                         X[i >> 1] = in.readInt() / 100000.0d;
                         ;
                     }
                     i++;
                 }
             } finally {
                 if ( in != null )
                     in.close();
             }
         }

         // standard -> china
         public PointDouble s2c(PointDouble pt) {
             int cnt = 10;
             double x = pt.x, y = pt.y;
             while ( cnt-- > 0 ) {
                 if ( x < 71.9989d || x > 137.8998d || y < 9.9997d || y > 54.8996d )
                     return pt;
                 int ix = (int) (10.0d * (x - 72.0d));
                 int iy = (int) (10.0d * (y - 10.0d));
                 double dx = (x - 72.0d - 0.1d * ix) * 10.0d;
                 double dy = (y - 10.0d - 0.1d * iy) * 10.0d;
                 x = (x + pt.x + (1.0d - dx) * (1.0d - dy) * X[ix + 660 * iy] + dx
                         * (1.0d - dy) * X[ix + 660 * iy + 1] + dx * dy
                         * X[ix + 660 * iy + 661] + (1.0d - dx) * dy
                         * X[ix + 660 * iy + 660] - x) / 2.0d;
                 y = (y + pt.y + (1.0d - dx) * (1.0d - dy) * Y[ix + 660 * iy] + dx
                         * (1.0d - dy) * Y[ix + 660 * iy + 1] + dx * dy
                         * Y[ix + 660 * iy + 661] + (1.0d - dx) * dy
                         * Y[ix + 660 * iy + 660] - y) / 2.0d;
             }
             return new PointDouble(x, y);
         }

         // china -> standard
         public PointDouble c2s(PointDouble pt) {
             int cnt = 10;
             double x = pt.x, y = pt.y;
             while ( cnt-- > 0 ) {
                 if ( x < 71.9989d || x > 137.8998d || y < 9.9997d || y > 54.8996d )
                     return pt;
                 int ix = (int) (10.0d * (x - 72.0d));
                 int iy = (int) (10.0d * (y - 10.0d));
                 double dx = (x - 72.0d - 0.1d * ix) * 10.0d;
                 double dy = (y - 10.0d - 0.1d * iy) * 10.0d;
                 x = (x + pt.x - (1.0d - dx) * (1.0d - dy) * X[ix + 660 * iy] - dx
                         * (1.0d - dy) * X[ix + 660 * iy + 1] - dx * dy
                         * X[ix + 660 * iy + 661] - (1.0d - dx) * dy
                         * X[ix + 660 * iy + 660] + x) / 2.0d;
                 y = (y + pt.y - (1.0d - dx) * (1.0d - dy) * Y[ix + 660 * iy] - dx
                         * (1.0d - dy) * Y[ix + 660 * iy + 1] - dx * dy
                         * Y[ix + 660 * iy + 661] - (1.0d - dx) * dy
                         * Y[ix + 660 * iy + 660] + y) / 2.0d;
             }
             return new PointDouble(x, y);
         }

     }

     static class PointDouble {
         double x, y;

         PointDouble(double x, double y) {
             this.x = x;
             this.y = y;
         }

         public String toString() {
             return "x=" + x + ", y=" + y;
         }
     }

 }