first commit

 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="VcsDirectoryMappings">
-    <mapping directory="" vcs="" />
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
   </component>
-</project>
-
+</project>
\ No newline at end of file

+## 项目说明
+
+TiandituDownload主要用于下载天地图数据，其坐标系为CGCS2000.
+
+```java
+
+// 设置要下载的图片存储sqlite路径
+TiandituDownload tiandituDownload = new TiandituDownload("my.db");
+// 范围起始点（左下角、右上角）
+Point pt = new Point(29.76,106.64);
+Point pt2 = new Point(35.33, 108.12);
+// 下载器
+// 2 为最小level，9为最大level，
+tiandituDownload.Download(pt, pt2, 2,9, TianDiTuTiledMapServiceType.IMG_C);
+
+```
\ No newline at end of file

+import utils.Point;
+import utils.TianDiTuTiledMapServiceType;
+
 import java.sql.SQLException;
 
 public class Main {
@@ -9,7 +12,7 @@ public class Main {
         TiandituDownload tiandituDownload = new TiandituDownload("my.db");
         Point pt = new Point(29.76,106.64);
         Point pt2 = new Point(35.33, 108.12);
-//        tiandituDownload.Download(pt, pt2, 9, TianDiTuTiledMapServiceType.IMG_C);
+//        tiandituDownload.Download(pt, pt2, 9, utils.TianDiTuTiledMapServiceType.IMG_C);
         tiandituDownload.Download(pt, pt2, 2,9, TianDiTuTiledMapServiceType.IMG_C);
     }
 }

+import utils.CalEnv;
+import utils.Point;
+import utils.TDTUrl;
+import utils.TianDiTuTiledMapServiceType;
+
 import java.io.BufferedInputStream;
 import java.io.ByteArrayOutputStream;
 import java.net.HttpURLConnection;

+package utils;
+
 public class CalEnv {
 
     private int startX;

+package utils;
+
 public class Point {
 
     private double lat;

@@ -2,6 +2,8 @@ package utils;
 
 import java.util.Random;
 
+import static utils.TianDiTuTiledMapServiceType.*;
+
 /**
  * Created by jiangbotao on 2018/3/23.
  */
@@ -27,28 +29,28 @@ public class TDTUrl {
         int subdomain = (random.nextInt(6) + 1);
         url.append(subdomain);
         switch (this._tiandituMapServiceType) {
-            case TianDiTuTiledMapServiceType.VEC_C:
+            case VEC_C:
                 url.append(".tianditu.com/DataServer?T=vec_c&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.CVA_C:
+            case CVA_C:
                 url.append(".tianditu.com/DataServer?T=cva_c&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.CIA_C:
+            case CIA_C:
                 url.append(".tianditu.com/DataServer?T=cia_c&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.IMG_C:
+            case IMG_C:
                 url.append(".tianditu.com/DataServer?T=img_c&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.VEC_W:
+            case VEC_W:
                 url.append(".tianditu.com/DataServer?T=vec_w&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.CVA_W:
+            case CVA_W:
                 url.append(".tianditu.com/DataServer?T=cva_w&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.CIA_W:
+            case CIA_W:
                 url.append(".tianditu.com/DataServer?T=cia_w&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
-            case TianDiTuTiledMapServiceType.IMG_W:
+            case IMG_W:
                 url.append(".tianditu.com/DataServer?T=img_w&X=").append(this._col).append("&Y=").append(this._row).append("&L=").append(this._level);
                 break;
             default:

+package utils;
 
 /**
  * Created by jiangbotao on 2018/3/23.