git.gag.com Git - debian/openrocket/blob - core/src/net/sf/openrocket/file/iterator/ZipDirectoryIterator.java

   1 package net.sf.openrocket.file.iterator;
   2
   3 import java.io.File;
   4 import java.io.FileFilter;
   5 import java.io.IOException;
   6 import java.io.InputStream;
   7 import java.util.Enumeration;
   8 import java.util.zip.ZipEntry;
   9 import java.util.zip.ZipFile;
  10
  11 import net.sf.openrocket.logging.LogHelper;
  12 import net.sf.openrocket.startup.Application;
  13 import net.sf.openrocket.util.Pair;
  14
  15 /**
  16  * A DirectoryIterator that reads files from the specified directory of a
  17  * ZIP (or JAR) file.
  18  *
  19  * TODO: MEDIUM: This is always a recursive search.
  20  *
  21  * @author Sampo Niskanen <sampo.niskanen@iki.fi>
  22  */
  23 public class ZipDirectoryIterator extends FileIterator {
  24
  25         private static final LogHelper logger = Application.getLogger();
  26
  27         private final File zipFileName;
  28         private final String directory;
  29         private final FileFilter filter;
  30
  31         private ZipFile zipFile;
  32         private Enumeration<? extends ZipEntry> entries;
  33
  34
  35         /**
  36          * Sole constructor.
  37          *
  38          * @param zipFileName   the ZIP file to read.
  39          * @param directory             the directory within the ZIP file to read, relative to the
  40          *                                              base (an empty string corresponds to the root directory)
  41          * @param filter                the filter for accepted files.
  42          * @throws IOException  if the ZIP file could not be read.
  43          */
  44         public ZipDirectoryIterator(File zipFileName, String directory, FileFilter filter)
  45                         throws IOException {
  46
  47                 // Process directory and extension
  48                 if (!directory.endsWith("/")) {
  49                         directory += "/";
  50                 }
  51
  52                 this.zipFileName = zipFileName;
  53                 this.directory = directory;
  54                 this.filter = filter;
  55
  56
  57                 // Loop through ZIP entries searching for files to load
  58                 this.zipFile = new ZipFile(zipFileName);
  59                 entries = zipFile.entries();
  60
  61         }
  62
  63
  64         @Override
  65         public void close() {
  66                 super.close();
  67                 if (zipFile != null) {
  68                         try {
  69                                 zipFile.close();
  70                         } catch (IOException e) {
  71                                 logger.error("Closing ZIP file failed", e);
  72                         }
  73                         zipFile = null;
  74                         entries = null;
  75                 }
  76         }
  77
  78
  79         @Override
  80         protected Pair<String, InputStream> findNext() {
  81                 if (entries == null) {
  82                         return null;
  83                 }
  84
  85                 while (entries.hasMoreElements()) {
  86                         ZipEntry entry = entries.nextElement();
  87                         String name = entry.getName();
  88                         File file = new File(name);
  89                         if (name.startsWith(directory) && filter.accept(file)) {
  90                                 try {
  91                                         InputStream is = zipFile.getInputStream(entry);
  92                                         return new Pair<String, InputStream>(name, is);
  93                                 } catch (IOException e) {
  94                                         logger.error("IOException when reading ZIP file " + zipFileName, e);
  95                                 }
  96                         }
  97                 }
  98
  99                 return null;
 100         }
 101
 102
 103 }