Examples of DBCursor

com.massivecraft.mcore.xlib.mongodb.DBCursor
An iterator over database results. Doing a find() query on a collection returns a DBCursor thus
```
 DBCursor cursor = collection.find( query ); if( cursor.hasNext() ) DBObject obj = cursor.next(); 
```
Warning: Calling toArray or length on a DBCursor will irrevocably turn it into an array. This means that, if the cursor was iterating over ten million results (which it was lazily fetching from the database), suddenly there will be a ten-million element array in memory. Before converting to an array, make sure that there are a reasonable number of results using skip() and limit().
For example, to get an array of the 1000-1100th elements of a cursor, use
```
 List obj = collection.find( query ).skip( 1000 ).limit( 100 ).toArray(); 
```
@dochub cursors
com.mongodb.DBCursor
An iterator over database results. Doing a find() query on a collection returns a DBCursor thus
```
 DBCursor cursor = collection.find( query ); if( cursor.hasNext() ) DBObject obj = cursor.next(); 
```
Warning: Calling toArray or length on a DBCursor will irrevocably turn it into an array. This means that, if the cursor was iterating over ten million results (which it was lazily fetching from the database), suddenly there will be a ten-million element array in memory. Before converting to an array, make sure that there are a reasonable number of results using skip() and limit().
For example, to get an array of the 1000-1100th elements of a cursor, use
```
 List obj = collection.find( query ).skip( 1000 ).limit( 100 ).toArray(); 
```
@dochub cursors
com.sun.sgs.service.store.db.DbCursor
The interface to a cursor for iterating over the contents of a database. A newly created cursor has no current key or value. Cursors are associated with a single transaction, and must be created and closed within that single transaction. Cursors must not be used after the {@link #close close} methodis called. Cursor implementations are not required to be synchronized.

Examples of com.mongodb.DBCursor

            queryBuilder.greaterThanEquals(startValue);
        }
        DBObject query = queryBuilder.get();
        long start = start();
        try {
            DBCursor cursor = dbCollection.find(query).sort(BY_ID_ASC);
            List<T> list;
            try {
                list = new ArrayList<T>();
                for (int i = 0; i < limit && cursor.hasNext(); i++) {
                    DBObject o = cursor.next();
                    T doc = convertFromDBObject(collection, o);
                    if (collection == Collection.NODES && doc != null) {
                        doc.seal();
                        String id = doc.getId();
                        Lock lock = getAndLock(id);
                        CacheValue cacheKey = new StringValue(id);
                        try {
                            // do not overwrite document in cache if the
                            // existing one in the cache is newer
                            NodeDocument cached = nodesCache.getIfPresent(cacheKey);
                            if (cached != null && cached != NodeDocument.NULL) {
                                // check mod count
                                Number cachedModCount = cached.getModCount();
                                Number modCount = doc.getModCount();
                                if (cachedModCount == null || modCount == null) {
                                    throw new IllegalStateException(
                                            "Missing " + Document.MOD_COUNT);
                                }
                                if (modCount.longValue() > cachedModCount.longValue()) {
                                    nodesCache.put(cacheKey, (NodeDocument) doc);
                                }
                            } else {
                                nodesCache.put(cacheKey, (NodeDocument) doc);
                            }
                        } finally {
                            lock.unlock();
                        }
                    }
                    list.add(doc);
                }
            } finally {
                cursor.close();
            }
            return list;
        } finally {
            end("query", start);
        }

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Examples of com.mongodb.DBCursor

        //_deletedOnce == true && _modified < lastModifiedTime
        DBObject query =
                start(NodeDocument.DELETED_ONCE).is(Boolean.TRUE)
                                .put(NodeDocument.MODIFIED_IN_SECS).lessThan(Commit.getModifiedInSecs(lastModifiedTime))
                        .get();
        DBCursor cursor = getNodeCollection().find(query).setReadPreference(ReadPreference.secondaryPreferred());
        return CloseableIterable.wrap(transform(cursor, new Function<DBObject, NodeDocument>() {
            @Override
            public NodeDocument apply(DBObject input) {
                return store.convertFromDBObject(Collection.NODES, input);
            }

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Examples of com.mongodb.DBCursor


    private void logSplitDocIdsTobeDeleted(DBObject query) {
        // Fetch only the id
        final BasicDBObject keys = new BasicDBObject(Document.ID, 1);
        List<String> ids;
        DBCursor cursor = getNodeCollection().find(query, keys)
                .setReadPreference(ReadPreference.secondaryPreferred());
        try {
             ids = ImmutableList.copyOf(Iterables.transform(cursor, new Function<DBObject, String>() {
                 @Override
                 public String apply(@Nullable DBObject input) {
                     return (String) input.get(Document.ID);
                 }
             }));
        } finally {
            cursor.close();
        }
        StringBuilder sb = new StringBuilder("Split documents with following ids were deleted as part of GC \n");
        Joiner.on(StandardSystemProperty.LINE_SEPARATOR.value()).appendTo(sb, ids);
        log.debug(sb.toString());
    }

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Examples of com.mongodb.DBCursor

                        .put(NodeDocument.MODIFIED_IN_SECS).greaterThanEquals(
                                Commit.getModifiedInSecs(startTime))
                        .get();
        DBObject sortFields = new BasicDBObject(NodeDocument.MODIFIED_IN_SECS, -1);


        DBCursor cursor =
                getNodeCollection().find(query)
                        .sort(sortFields)
                        .setReadPreference(
                                ReadPreference.secondaryPreferred());
        return CloseableIterable.wrap(transform(cursor, new Function<DBObject, NodeDocument>() {

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Examples of com.mongodb.DBCursor

            // Fetch only the lastRev map and id
            final BasicDBObject keys = new BasicDBObject(Document.ID, 1);
            keys.put(Document.MOD_COUNT, 1);


            // Fetch lastRev for each such node
            DBCursor cursor = nodes.find(query.get(), keys);
            result.queryCount++;


            for (DBObject obj : cursor) {
                result.cacheEntriesProcessedCount++;
                String id = (String) obj.get(Document.ID);

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Examples of com.mongodb.DBCursor


                        QueryBuilder query = QueryBuilder.start(Document.ID)
                                .in(idBatch);


                        // Fetch lastRev and modCount for each such nodes
                        DBCursor cursor = nodes.find(query.get(), keys);
                        LOG.debug(
                                "Checking for changed nodes at level {} with {} paths",
                                tn.level(), sameLevelNodes.size());
                        result.queryCount++;
                        try {
                            for (DBObject obj : cursor) {


                                result.cacheEntriesProcessedCount++;


                                Number latestModCount = (Number) obj.get(Document.MOD_COUNT);
                                String id = (String) obj.get(Document.ID);


                                final TreeNode tn2 = sameLevelNodes.get(id);
                                CachedNodeDocument cachedDoc = tn2.getDocument();
                                if (cachedDoc != null) {
                                    boolean noChangeInModCount = Objects.equal(latestModCount, cachedDoc.getModCount());
                                    if (noChangeInModCount) {
                                        result.upToDateCount++;
                                        tn2.markUptodate(startTime);
                                    } else {
                                        result.invalidationCount++;
                                        tn2.invalidate();
                                    }
                                }


                                // Remove the processed nodes
                                sameLevelNodes.remove(tn2.getId());
                            }
                        } finally {
                            cursor.close();
                        }
                    }


                    // NodeDocument present in cache but not in database
                    // Remove such nodes from cache

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Examples of com.mongodb.DBCursor

  public void testCollectionViaCursor() throws UnknownHostException, MongoException {
    MongoDao dao = MongoDao.Factory.newTestMongoDao();
    
    DBCollection col = dao.getDbCollection();
    
    DBCursor cur = col.find();


        while(cur.hasNext()) {
            System.out.println(cur.next());
        }
  }

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Examples of com.mongodb.DBCursor

  }


  @Override
  public Collection<PropertyRecord> find(String propertyName,
      String propertyValue) {
    DBCursor dbCursor = this.dbCollection.find(new BasicDBObject(
        propertyName, propertyValue));
    if (dbCursor == null)
      return null;
    return new PropertyRecordList(dbCursor);
  }

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Examples of com.mongodb.DBCursor

      if (property.getValue() instanceof String) {
        queryParts.add(queryPart);
      }
    }
    logger.debug("query: " + query);
    DBCursor dbCursor = this.dbCollection.find(query);
    if (dbCursor == null)
      return null;
    return new PropertyRecordList(dbCursor);
  }

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Examples of com.sun.sgs.service.store.db.DbCursor

      infoDb.get(dbTxn, firstPlaceholderKey, true));
  if (placeholderOid < 0) {
      logger.log(Level.FINEST, "No allocation placeholders");
      return;
  }
  DbCursor cursor = oidsDb.openCursor(dbTxn);
  try {
      while (cursor.findNext(DataEncoding.encodeLong(placeholderOid))) {
    byte[] key = cursor.getKey();
    if (DataEncoding.decodeLong(key) != placeholderOid) {
        if (logger.isLoggable(Level.FINEST)) {
      logger.log(Level.FINEST,
           "Placeholder oid:{0,number,#} not found",
           placeholderOid);
        }
    } else if (isPlaceholderValue(cursor.getValue())) {
        boolean success = oidsDb.delete(dbTxn, key);
        assert success;
        if (logger.isLoggable(Level.FINEST)) {
      logger.log(Level.FINEST,
           "Removed placeholder at oid:{0,number,#}",
           placeholderOid);
        }
    } else {
        if (logger.isLoggable(Level.FINEST)) {
      logger.log(Level.FINEST,
           "Ignoring oid:{0,number,#} that does not" +
           " refer to a placeholder",
           placeholderOid);
        }
    }
    placeholderOid += ALLOCATION_BLOCK_SIZE;
      }
      infoDb.put(
    dbTxn, firstPlaceholderKey, DataEncoding.encodeLong(-1));
  } finally {
      cursor.close();
  }
    }

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