コード例 #1
0
 /* write a chunk data to the region file at specified sector number */
 private void write(int sectorNumber, byte[] data, int length) throws IOException {
   debugln(" " + sectorNumber);
   file.seek(sectorNumber * SECTOR_BYTES);
   file.writeInt(length + 1); // chunk length
   file.writeByte(VERSION_DEFLATE); // chunk version number
   file.write(data, 0, length); // chunk data
 }
コード例 #2
0
  public RegionFile(File path) {
    offsets = new int[SECTOR_INTS];
    chunkTimestamps = new int[SECTOR_INTS];

    fileName = path;
    debugln("REGION LOAD " + fileName);

    sizeDelta = 0;

    try {
      if (path.exists()) {
        lastModified = path.lastModified();
      }

      file = new RandomAccessFile(path, "rw");

      if (file.length() < SECTOR_BYTES) {
        /* we need to write the chunk offset table */
        for (int i = 0; i < SECTOR_INTS; ++i) {
          file.writeInt(0);
        }
        // write another sector for the timestamp info
        for (int i = 0; i < SECTOR_INTS; ++i) {
          file.writeInt(0);
        }

        sizeDelta += SECTOR_BYTES * 2;
      }

      if ((file.length() & 0xfff) != 0) {
        /* the file size is not a multiple of 4KB, grow it */
        for (int i = 0; i < (file.length() & 0xfff); ++i) {
          file.write((byte) 0);
        }
      }

      /* set up the available sector map */
      int nSectors = (int) file.length() / SECTOR_BYTES;
      sectorFree = new ArrayList<Boolean>(nSectors);

      for (int i = 0; i < nSectors; ++i) {
        sectorFree.add(true);
      }

      sectorFree.set(0, false); // chunk offset table
      sectorFree.set(1, false); // for the last modified info

      file.seek(0);
      for (int i = 0; i < SECTOR_INTS; ++i) {
        int offset = file.readInt();
        offsets[i] = offset;
        if (offset != 0 && (offset >> 8) + (offset & 0xFF) <= sectorFree.size()) {
          for (int sectorNum = 0; sectorNum < (offset & 0xFF); ++sectorNum) {
            sectorFree.set((offset >> 8) + sectorNum, false);
          }
        }
      }
      for (int i = 0; i < SECTOR_INTS; ++i) {
        int lastModValue = file.readInt();
        chunkTimestamps[i] = lastModValue;
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
コード例 #3
0
 private void setTimestamp(int x, int z, int value) throws IOException {
   chunkTimestamps[x + z * 32] = value;
   file.seek(SECTOR_BYTES + (x + z * 32) * 4);
   file.writeInt(value);
 }
コード例 #4
0
 private void setOffset(int x, int z, int offset) throws IOException {
   offsets[x + z * 32] = offset;
   file.seek((x + z * 32) * 4);
   file.writeInt(offset);
 }