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