git.gag.com Git - fw/altos/blob - altosui/AltosSiteMapCache.java

   1 /*
   2  * Copyright © 2010 Anthony Towns <aj@erisian.com.au>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  16  */
  17
  18 package altosui;
  19
  20 import javax.swing.*;
  21 import javax.imageio.ImageIO;
  22 import java.awt.image.*;
  23 import java.io.*;
  24 import java.net.URL;
  25 import java.net.URLConnection;
  26
  27 public class AltosSiteMapCache extends JLabel {
  28         public static boolean fetchMap(File file, String url) {
  29                 URL u;
  30
  31                 try {
  32                         u = new URL(url);
  33                 } catch (java.net.MalformedURLException e) {
  34                         return false;
  35                 }
  36
  37                 byte[] data;
  38                 try {
  39                         URLConnection uc = u.openConnection();
  40                         int contentLength = uc.getContentLength();
  41                         InputStream in = new BufferedInputStream(uc.getInputStream());
  42                         int bytesRead = 0;
  43                         int offset = 0;
  44                         data = new byte[contentLength];
  45                         while (offset < contentLength) {
  46                                 bytesRead = in.read(data, offset, data.length - offset);
  47                                 if (bytesRead == -1)
  48                                         break;
  49                                 offset += bytesRead;
  50                         }
  51                         in.close();
  52
  53                         if (offset != contentLength) {
  54                                 return false;
  55                         }
  56                 } catch (IOException e) {
  57                         return false;
  58                 }
  59
  60                 try {
  61                         FileOutputStream out = new FileOutputStream(file);
  62                         out.write(data);
  63                         out.flush();
  64                         out.close();
  65                 } catch (FileNotFoundException e) {
  66                         return false;
  67                 } catch (IOException e) {
  68                         if (file.exists()) {
  69                                 file.delete();
  70                         }
  71                         return false;
  72                 }
  73                 return true;
  74         }
  75
  76         public static ImageIcon fetchAndLoadMap(File pngfile, String url) {
  77                 if (!pngfile.exists()) {
  78                         if (!fetchMap(pngfile, url)) {
  79                                 return null;
  80                         }
  81                 }
  82                 return loadMap(pngfile, url);
  83         }
  84
  85         public static ImageIcon loadMap(File pngfile, String url) {
  86                 if (!pngfile.exists()) {
  87                         return null;
  88                 }
  89
  90                 try {
  91                         BufferedImage   img;
  92
  93                         img = ImageIO.read(pngfile);
  94                         if (img == null) {
  95                                 System.out.printf("# Can't read pngfile %s\n", pngfile);
  96                                 return null;
  97                         }
  98                         return new ImageIcon(img);
  99                 } catch (IOException e) {
 100                         System.out.printf("# IO error trying to load %s\n", pngfile);
 101                         return null;
 102                 }
 103         }
 104 }