tim/prune/load/MediaHelper.java

   1 package tim.prune.load;
   2
   3 import java.io.File;
   4 import java.io.IOException;
   5 import java.io.InputStream;
   6 import java.net.URL;
   7 import java.util.zip.ZipEntry;
   8 import java.util.zip.ZipFile;
   9
  10 import tim.prune.data.AudioClip;
  11 import tim.prune.data.MediaObject;
  12 import tim.prune.data.Photo;
  13
  14 /**
  15  * Class to provide helper functions for loading media
  16  */
  17 public abstract class MediaHelper
  18 {
  19         /** File filters */
  20         private static GenericFileFilter _jpegFilter = null, _audioFilter = null;
  21
  22
  23         /**
  24          * Construct a MediaObject for the given path
  25          * @param inZipFile path to archive file (if any)
  26          * @param inPath path to media file
  27          * @param inSourceFile file from which data was loaded
  28          * @return either Photo or AudioClip object as appropriate, or null
  29          */
  30         public static MediaObject createMediaObject(File inZipFile, String inPath, File inSourceFile)
  31         {
  32                 if (inPath == null || inPath.length() < 5) return null;
  33                 InputStream is = null;
  34                 ZipFile zf     = null;
  35                 byte[] data    = null;
  36                 String url     = null;
  37                 try
  38                 {
  39                         // Check if path is a URL, in which case get an input stream from it
  40                         if (inPath.substring(0, 5).toLowerCase().equals("http:"))
  41                         {
  42                                 url = inPath;
  43                                 is = new URL(inPath).openStream();
  44                                 data = ByteScooper.scoop(is);
  45                         }
  46                 }
  47                 catch (IOException ioe) {
  48                         System.err.println("Got ioe from url: " + ioe.getMessage());
  49                 } // is stays null
  50
  51                 // Now see if file is in the zip file
  52                 if (is == null && inZipFile != null && inZipFile.exists() && inZipFile.canRead())
  53                 {
  54                         try
  55                         {
  56                                 zf = new ZipFile(inZipFile);
  57                                 ZipEntry entry = zf.getEntry(inPath);
  58                                 if (entry != null && entry.getSize() > 0)
  59                                 {
  60                                         data = ByteScooper.scoop(zf.getInputStream(entry));
  61                                         // System.out.println("Size of data " + (data.length == entry.getSize()?"matches":"DOESN'T match"));
  62                                 }
  63                         }
  64                         catch (IOException ioe) {
  65                                 System.err.println("Got ioe from zip file: " + ioe.getMessage());
  66                         }
  67                 }
  68                 // Clean up input streams
  69                 if (is != null) try {
  70                         is.close();
  71                 } catch (IOException ioe) {}
  72                 if (zf != null) try {
  73                         zf.close();
  74                 } catch (IOException ioe) {}
  75
  76                 if (data != null)
  77                 {
  78                         // Create Photo or AudioClip using this entry
  79                         String filename = new File(inPath).getName();
  80                         initFilters();
  81                         if (_jpegFilter.acceptFilename(inPath)) {
  82                                 return new Photo(data, filename, url);
  83                         }
  84                         else if (_audioFilter.acceptFilename(inPath)) {
  85                                 return new AudioClip(data, filename, url);
  86                         }
  87                         return null;
  88                 }
  89
  90                 // If we haven't got a result by now, try to load plain file
  91                 File file = new File(inPath);
  92                 if (inSourceFile != null && !file.isAbsolute()) {
  93                         file = new File(inSourceFile.getParent(), inPath);
  94                 }
  95                 // awkward construction because new File(startPath, absolutePath) doesn't work
  96                 return createMediaObject(file);
  97         }
  98
  99         /**
 100          * Construct a MediaObject for the given file
 101          * @param inFile file to load
 102          * @return either Photo or AudioClip object as appropriate, or null
 103          */
 104         private static MediaObject createMediaObject(File inFile)
 105         {
 106                 if (inFile == null) {return null;}
 107                 if (!inFile.exists() || !inFile.canRead() || !inFile.isFile()) {return null;}
 108                 initFilters();
 109                 // Check if filename looks like a jpeg
 110                 if (_jpegFilter.acceptFilename(inFile.getName())) {
 111                         return JpegLoader.createPhoto(inFile);
 112                 }
 113                 // Check if filename looks like an audio clip
 114                 if (_audioFilter.acceptFilename(inFile.getName())) {
 115                         return new AudioClip(inFile);
 116                 }
 117                 // Neither photo nor audio
 118                 return null;
 119         }
 120
 121         /**
 122          * Initialise filters if necessary
 123          */
 124         private static void initFilters()
 125         {
 126                 if (_jpegFilter == null) {
 127                         _jpegFilter = new JpegFileFilter();
 128                         _audioFilter = new AudioFileFilter();
 129                 }
 130         }
 131 }