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

   1 package net.sf.openrocket.file;
   2
   3 import java.io.BufferedInputStream;
   4 import java.io.IOException;
   5 import java.io.InputStream;
   6 import java.nio.charset.Charset;
   7 import java.util.Arrays;
   8 import java.util.zip.GZIPInputStream;
   9 import java.util.zip.ZipEntry;
  10 import java.util.zip.ZipInputStream;
  11
  12 import net.sf.openrocket.document.OpenRocketDocument;
  13 import net.sf.openrocket.file.openrocket.importt.OpenRocketLoader;
  14 import net.sf.openrocket.file.rocksim.importt.RocksimLoader;
  15 import net.sf.openrocket.util.TextUtil;
  16
  17
  18 /**
  19  * A rocket loader that auto-detects the document type and uses the appropriate
  20  * loading.  Supports loading of GZIPed files as well with transparent
  21  * uncompression.
  22  *
  23  * @author Sampo Niskanen <sampo.niskanen@iki.fi>
  24  */
  25 public class GeneralRocketLoader extends AbstractRocketLoader {
  26
  27         private static final int READ_BYTES = 300;
  28
  29         private static final byte[] GZIP_SIGNATURE = { 31, -117 }; // 0x1f, 0x8b
  30         private static final byte[] ZIP_SIGNATURE = TextUtil.convertStringToBytes("PK",Charset.forName("US-ASCII"));
  31         private static final byte[] OPENROCKET_SIGNATURE = TextUtil.convertStringToBytes("<openrocket",Charset.forName("US-ASCII"));
  32         private static final byte[] ROCKSIM_SIGNATURE = TextUtil.convertStringToBytes("<RockSimDoc",Charset.forName("US-ASCII"));
  33
  34         private final OpenRocketLoader openRocketLoader = new OpenRocketLoader();
  35
  36         private final RocksimLoader rocksimLoader = new RocksimLoader();
  37
  38         @Override
  39         protected OpenRocketDocument loadFromStream(InputStream source, MotorFinder motorFinder) throws IOException,
  40                         RocketLoadException {
  41
  42                 // Check for mark() support
  43                 if (!source.markSupported()) {
  44                         source = new BufferedInputStream(source);
  45                 }
  46
  47                 // Read using mark()
  48                 byte[] buffer = new byte[READ_BYTES];
  49                 int count;
  50                 source.mark(READ_BYTES + 10);
  51                 count = source.read(buffer);
  52                 source.reset();
  53
  54                 if (count < 10) {
  55                         throw new RocketLoadException("Unsupported or corrupt file.");
  56                 }
  57
  58                 // Detect the appropriate loader
  59
  60                 // Check for GZIP
  61                 if (buffer[0] == GZIP_SIGNATURE[0] && buffer[1] == GZIP_SIGNATURE[1]) {
  62                         OpenRocketDocument doc = loadFromStream(new GZIPInputStream(source), motorFinder);
  63                         doc.getDefaultStorageOptions().setCompressionEnabled(true);
  64                         return doc;
  65                 }
  66
  67                 // Check for ZIP (for future compatibility)
  68                 if (buffer[0] == ZIP_SIGNATURE[0] && buffer[1] == ZIP_SIGNATURE[1]) {
  69                         // Search for entry with name *.ork
  70                         ZipInputStream in = new ZipInputStream(source);
  71                         while (true) {
  72                                 ZipEntry entry = in.getNextEntry();
  73                                 if (entry == null) {
  74                                         throw new RocketLoadException("Unsupported or corrupt file.");
  75                                 }
  76                                 if (entry.getName().matches(".*\\.[oO][rR][kK]$")) {
  77                                         OpenRocketDocument doc = loadFromStream(in, motorFinder);
  78                                         doc.getDefaultStorageOptions().setCompressionEnabled(true);
  79                                         return doc;
  80                                 }
  81                         }
  82                 }
  83
  84                 // Check for OpenRocket
  85                 int match = 0;
  86                 for (int i = 0; i < count; i++) {
  87                         if (buffer[i] == OPENROCKET_SIGNATURE[match]) {
  88                                 match++;
  89                                 if (match == OPENROCKET_SIGNATURE.length) {
  90                                         return loadUsing(source, openRocketLoader, motorFinder);
  91                                 }
  92                         } else {
  93                                 match = 0;
  94                         }
  95                 }
  96
  97                 byte[] typeIdentifier = Arrays.copyOf(buffer, ROCKSIM_SIGNATURE.length);
  98                 if (Arrays.equals(ROCKSIM_SIGNATURE, typeIdentifier)) {
  99                         return loadUsing(source, rocksimLoader, motorFinder);
 100                 }
 101                 throw new RocketLoadException("Unsupported or corrupt file.");
 102         }
 103
 104         private OpenRocketDocument loadUsing(InputStream source, RocketLoader loader, MotorFinder motorFinder)
 105                         throws RocketLoadException {
 106                 warnings.clear();
 107                 OpenRocketDocument doc = loader.load(source, motorFinder);
 108                 warnings.addAll(loader.getWarnings());
 109                 return doc;
 110         }
 111 }