How to use

findMaxPrefix

method

in

org.apache.zookeeper.common.PathTrie

/**
 * If there is a quota set, return the appropriate prefix for that quota
 * Else return null
 * @param path The ZK path to check for quota
 * @return Max quota prefix, or null if none
 */
public String getMaxPrefixWithQuota(String path) {
  // do nothing for the root.
  // we are not keeping a quota on the zookeeper
  // root node for now.
  String lastPrefix = pTrie.findMaxPrefix(path);
  if (rootZookeeper.equals(lastPrefix) || "".equals(lastPrefix)) {
    return null;
  }
  else {
    return lastPrefix;
  }
}

/**
 * If there is a quota set, return the appropriate prefix for that quota
 * Else return null
 * @param path The ZK path to check for quota
 * @return Max quota prefix, or null if none
 */
public String getMaxPrefixWithQuota(String path) {
  // do nothing for the root.
  // we are not keeping a quota on the zookeeper
  // root node for now.
  String lastPrefix = pTrie.findMaxPrefix(path);
  if (!rootZookeeper.equals(lastPrefix) && !("".equals(lastPrefix))) {
    return lastPrefix;
  }
  else {
    return null;
  }
}

@Test(timeout = 60000)
public void testPathTrieClearOnDeserialize() throws Exception {
  //Create a DataTree with quota nodes so PathTrie get updated
  DataTree dserTree = new DataTree();
  dserTree.createNode("/bug", new byte[20], null, -1, 1, 1, 1);
  dserTree.createNode(Quotas.quotaZookeeper+"/bug", null, null, -1, 1, 1, 1);
  dserTree.createNode(Quotas.quotaPath("/bug"), new byte[20], null, -1, 1, 1, 1);
  dserTree.createNode(Quotas.statPath("/bug"), new byte[20], null, -1, 1, 1, 1);
  //deserialize a DataTree; this should clear the old /bug nodes and pathTrie
  DataTree tree = new DataTree();
  ByteArrayOutputStream baos = new ByteArrayOutputStream();
  BinaryOutputArchive oa = BinaryOutputArchive.getArchive(baos);
  tree.serialize(oa, "test");
  baos.flush();
  ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
  BinaryInputArchive ia = BinaryInputArchive.getArchive(bais);
  dserTree.deserialize(ia, "test");
  Field pfield = DataTree.class.getDeclaredField("pTrie");
  pfield.setAccessible(true);
  PathTrie pTrie = (PathTrie)pfield.get(dserTree);
  //Check that the node path is removed from pTrie
  Assert.assertEquals("/bug is still in pTrie", "", pTrie.findMaxPrefix("/bug"));
}

public Stat setData(String path, byte data[], int version, long zxid,
    long time) throws KeeperException.NoNodeException {
  Stat s = new Stat();
  DataNode n = nodes.get(path);
  if (n == null) {
    throw new KeeperException.NoNodeException();
  }
  byte lastdata[] = null;
  synchronized (n) {
    lastdata = n.data;
    n.data = data;
    n.stat.setMtime(time);
    n.stat.setMzxid(zxid);
    n.stat.setVersion(version);
    n.copyStat(s);
  }
  // now update if the path is in a quota subtree.
  String lastPrefix = pTrie.findMaxPrefix(path);
  // do nothing for the root.
  // we are not keeping a quota on the zookeeper
  // root node for now.
  if (!rootZookeeper.equals(lastPrefix) && !("".equals(lastPrefix))) {
    this.updateBytes(lastPrefix, (data == null ? 0 : data.length)
        - (lastdata == null ? 0 : lastdata.length));
  }
  dataWatches.triggerWatch(path, EventType.NodeDataChanged);
  return s;
}

String lastPrefix = pTrie.findMaxPrefix(path);
if (!rootZookeeper.equals(lastPrefix) && !("".equals(lastPrefix))) {

String lastPrefix = pTrie.findMaxPrefix(path);
if (!rootZookeeper.equals(lastPrefix) && !("".equals(lastPrefix))) {