public void prepare(ColumnFamilyStore cfs) {
      if (tree.partitioner() instanceof RandomPartitioner) {
        // You can't beat an even tree distribution for md5
        tree.init();
      } else {
        List<DecoratedKey> keys = new ArrayList<DecoratedKey>();
        for (DecoratedKey sample : cfs.keySamples(request.range)) {
          assert request.range.contains(sample.token)
              : "Token " + sample.token + " is not within range " + request.range;
          keys.add(sample);
        }

        if (keys.isEmpty()) {
          // use an even tree distribution
          tree.init();
        } else {
          int numkeys = keys.size();
          Random random = new Random();
          // sample the column family using random keys from the index
          while (true) {
            DecoratedKey dk = keys.get(random.nextInt(numkeys));
            if (!tree.split(dk.token)) break;
          }
        }
      }
      logger.debug("Prepared AEService tree of size " + tree.size() + " for " + request);
      ranges = tree.invalids();
    }
示例#2
0
  @Test
  public void testDifference() {
    Range full = new Range(tok(-1), tok(-1));
    int maxsize = 16;
    mt.maxsize(maxsize);
    MerkleTree mt2 = new MerkleTree(partitioner, RECOMMENDED_DEPTH, maxsize);
    mt.init();
    mt2.init();

    TreeRange leftmost = null;
    TreeRange middle = null;
    TreeRange rightmost = null;

    // compact the leftmost, and split the rightmost
    Iterator<TreeRange> ranges = mt.invalids(full);
    leftmost = ranges.next();
    rightmost = null;
    while (ranges.hasNext()) rightmost = ranges.next();
    mt.compact(leftmost.right);
    leftmost = mt.get(leftmost.right); // leftmost is now a larger range
    mt.split(rightmost.right);

    // set the hash for the left neighbor of rightmost
    middle = mt.get(rightmost.left);
    middle.hash("arbitrary!".getBytes());
    byte depth = middle.depth;

    // add dummy hashes to the rest of both trees
    for (TreeRange range : mt.invalids(full)) range.addAll(new HIterator(range.right));
    for (TreeRange range : mt2.invalids(full)) range.addAll(new HIterator(range.right));

    // trees should disagree for leftmost, (middle.left, rightmost.right]
    List<TreeRange> diffs = MerkleTree.difference(mt, mt2);
    assertEquals(diffs + " contains wrong number of differences:", 2, diffs.size());
    assertTrue(diffs.contains(leftmost));
    assertTrue(diffs.contains(new Range(middle.left, rightmost.right)));
  }
示例#3
0
  @Test
  public void testSerialization() throws Exception {
    Range full = new Range(tok(-1), tok(-1));
    ByteArrayOutputStream bout = new ByteArrayOutputStream();
    ObjectOutputStream oout = new ObjectOutputStream(bout);

    // populate and validate the tree
    mt.maxsize(256);
    mt.init();
    for (TreeRange range : mt.invalids(full)) range.addAll(new HIterator(range.right));

    byte[] initialhash = mt.hash(full);
    oout.writeObject(mt);
    oout.close();

    ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
    ObjectInputStream oin = new ObjectInputStream(bin);
    MerkleTree restored = (MerkleTree) oin.readObject();

    // restore partitioner after serialization
    restored.partitioner(partitioner);

    assertHashEquals(initialhash, restored.hash(full));
  }