Example usage for com.mongodb DBCursor skip

List of usage examples for com.mongodb DBCursor skip

Introduction

In this page you can find the example usage for com.mongodb DBCursor skip.

Prototype

public DBCursor skip(final int numberOfElements) 

Source Link

Document

Discards a given number of elements at the beginning of the cursor.

Usage

From source file:io.liveoak.mongo.MongoCollectionResource.java

License:Open Source License

@Override
public Collection<Resource> members(RequestContext ctx) throws Exception {

    LinkedList<Resource> members = new LinkedList<>();

    DBObject returnFields = new BasicDBObject();
    if (ctx.returnFields() != null && !ctx.returnFields().child(LiveOak.MEMBERS).isEmpty()) {
        ReturnFields membersReturnFields = ctx.returnFields().child(LiveOak.MEMBERS);
        if (!membersReturnFields.isAll()) {
            membersReturnFields.forEach((fieldName) -> {
                returnFields.put(fieldName, true);
            });/*ww  w.j  av  a 2 s.c  o m*/
        }
    }

    DBCursor dbCursor = dbCollection.find(queryObject, returnFields);

    ResourceParams resourceParams = ctx.resourceParams();
    if (resourceParams != null && resourceParams.contains("hint")) {
        String hint = resourceParams.value("hint");
        if (hint.startsWith("{")) {
            try {
                DBObject hintObject = (DBObject) JSON.parse(hint);
                dbCursor.hint(hintObject);
            } catch (Exception e) {
                throw new NotAcceptableException(uri().toString(),
                        "Invalid JSON format for the 'hint' parameter", e);
            }
        } else {
            dbCursor.hint(hint);
        }
    }

    if (explainQuery) {
        members.add(new MongoEmbeddedObjectResource(this, dbCursor.explain()));
    } else {
        Sorting sorting = ctx.sorting();
        if (sorting != null) {
            BasicDBObject sortingObject = new BasicDBObject();
            for (Sorting.Spec spec : sorting) {
                sortingObject.append(spec.name(), spec.ascending() ? 1 : -1);
            }
            dbCursor = dbCursor.sort(sortingObject);
        }

        Pagination pagination = ctx.pagination();
        if (pagination != null) {
            dbCursor.limit(pagination.limit());
            dbCursor.skip(pagination.offset());
        }

        try {
            dbCursor.hasNext();
        } catch (Exception e) {
            throw new ResourceProcessingException(
                    "Exception encountered trying to fetch data from the Mongo Database", e);
        }

        dbCursor.forEach((dbObject) -> {
            members.add(new MongoBaseObjectResource(this, dbObject));
        });
    }

    return members;
}

From source file:jahspotify.storage.statistics.MongoDBHistoricalStorage.java

License:Apache License

@Override
public Collection<TrackHistory> getHistory(final int index, final int count,
        final HistoryCriteria... historyCriterias) {
    final DBCollection tracks = _db.getCollection("history");

    final DBCursor dbObjects = tracks.find();
    dbObjects.skip(index);
    dbObjects.limit(count);//from  ww  w  . j  a  v  a2s  .c  o  m
    final BasicDBObject orderBy = new BasicDBObject();
    orderBy.put("startTime", -1);
    dbObjects.sort(orderBy);

    return new AbstractCollection<TrackHistory>() {
        @Override
        public Iterator<TrackHistory> iterator() {
            return new MongoDBHistoryCursor(dbObjects);
        }

        @Override
        public int size() {
            return dbObjects.size();
        }
    };
}

From source file:me.carbou.mathieu.tictactoe.db.DBCollection.java

License:Apache License

public Stream<Map<String, Object>> find(Map where, Map fields, Map sort, Function<Map, Map> transform,
        int limit, int skip) {
    final DBCursor cursor = getCollection().find(new BasicDBObject(addWhere(where)),
            new BasicDBObject(preFind(fields)));
    if (!sort.isEmpty())
        cursor.sort(new BasicDBObject(sort));
    if (skip > 0)
        cursor.skip(skip);
    if (limit > DB.NO_LIMIT)
        cursor.limit(limit);/*  w  w w  .  j a va 2s .c  o m*/
    int est = cursor.size();
    Spliterator<Map<String, Object>> spliterator = new Spliterators.AbstractSpliterator<Map<String, Object>>(
            est, NONNULL | ORDERED | SIZED | IMMUTABLE) {
        @Override
        public boolean tryAdvance(Consumer<? super Map<String, Object>> action) {
            if (cursor.hasNext()) {
                action.accept(postFind(where, cursor.next(), transform));
                return true;
            } else {
                cursor.close();
                return false;
            }
        }
    };
    return StreamSupport.stream(spliterator, false);
}

From source file:me.yyam.mongodbutils.MongoDbOperater.java

public List find(QueryInfo queryInfo) {
    DB db = mongoClient.getDB(queryInfo.dbName);
    DBCollection coll = db.getCollection(queryInfo.collName);
    DBCursor cursor = null;
    if (queryInfo.query != null) {
        cursor = coll.find(queryInfo.query);
    } else {//from w ww . j a  v a 2 s . co m
        cursor = coll.find();
    }
    if (queryInfo.order != null) {
        cursor = cursor.sort(queryInfo.order);
    }
    if (queryInfo.limit != null) {
        cursor.limit(queryInfo.limit.intValue());
    }
    if (queryInfo.skip != null) {
        cursor.skip(queryInfo.skip.intValue());
    }
    return cursor2list(cursor);
}

From source file:me.yyam.mongodbutils.MongoDbOperater.java

public List<Map> find(DBCollection coll, DBObject query, DBObject order, int start, int limit) {
    DBCursor cursor = null;
    if (query == null) {
        cursor = coll.find();//w w w .  j  a v  a 2  s . co  m
    } else {
        cursor = coll.find(query);
    }

    if (order != null)
        cursor = cursor.sort(order);

    if (start != 0 && limit != 0) {
        cursor.skip(start).limit(limit);
    }
    if (start == 0 && limit != 0) {
        cursor.limit(limit);
    }

    return cursor2list(cursor);
}

From source file:mongodb.findPagging.java

public static void pageResults(DBCollection collection, Integer skip) {
    BasicDBObject query = new BasicDBObject("first", "w");
    DBCursor cursor = collection.find(query);
    cursor.sort(new BasicDBObject("word", 1));
    cursor.limit(10);//from ww  w  .  j  av a  2 s  .  c  o  m
    cursor.skip(skip);
    System.out.println("Page " + new Integer(skip + 1).toString() + " to "
            + new Integer(skip + cursor.size()).toString() + ":");
    findPagging.displayCursor(cursor);
    if (cursor.size() == 10) {
        findPagging.pageResults(collection, skip + 10);
    }
}

From source file:net.kamradtfamily.mongorest.AggregateServlet.java

License:GNU General Public License

@Override
protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

    log.fine("doPost()");

    InputStream is = req.getInputStream();
    String db_name = req.getParameter("dbname");
    String col_name = req.getParameter("colname");
    if (db_name == null || col_name == null) {
        error(res, SC_BAD_REQUEST, Status.get("param name missing"));
        return;/*w w  w  .j a  v a  2  s  . co  m*/
    }
    String skip = req.getParameter("skip");
    String limit = req.getParameter("limit");

    DB db = mongo.getDB(db_name);
    DBCollection col = db.getCollection(col_name);

    BufferedReader r = null;
    DBObject q = null, sort = null;
    try {

        r = new BufferedReader(new InputStreamReader(is));
        String data = r.readLine();
        if (data == null) {
            error(res, SC_BAD_REQUEST, Status.get("no data"));
            return;
        }
        try {
            q = (DBObject) JSON.parse(data);
        } catch (JSONParseException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse data"));
            return;
        }
        // sort param
        data = r.readLine();
        if (data != null) {
            try {
                sort = (DBObject) JSON.parse(data);
            } catch (JSONParseException e) {
                error(res, SC_BAD_REQUEST, Status.get("can not parse sort arg"));
                return;
            }
        }

    } finally {
        if (r != null)
            r.close();
    }

    DBCursor c;
    if (sort == null)
        c = col.find(q);
    else
        c = col.find(q).sort(sort);
    if (c == null) {
        error(res, SC_NOT_FOUND, Status.get("no documents found"));
        return;
    }

    res.setIntHeader("X-Documents-Count", c.count());

    if (limit != null) {
        try {
            c.limit(Math.min(Integer.parseInt(limit), MAX_FIELDS_TO_RETURN));
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse limit"));
            c.close();
            return;
        }
    } else
        c.limit(MAX_FIELDS_TO_RETURN);

    if (skip != null) {
        try {
            c.skip(Integer.parseInt(skip));
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse skip"));
            c.close();
            return;
        }
    }

    StringBuilder buf = tl.get();
    // reset buf
    buf.setLength(0);

    int no = 0;
    buf.append("[");
    while (c.hasNext()) {

        DBObject o = c.next();
        JSON.serialize(o, buf);
        buf.append(",");
        no++;

    }

    if (no > 0)
        buf.setCharAt(buf.length() - 1, ']');
    else
        buf.append(']');

    res.setIntHeader("X-Documents-Returned", no);

    out_str(req, buf.toString(), "application/json");

}

From source file:net.kamradtfamily.mongorest.AggregateServlet.java

License:GNU General Public License

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

    log.fine("doGet()");

    String db_name = req.getParameter("dbname");
    String col_name = req.getParameter("colname");
    if (db_name == null || col_name == null) {
        error(res, SC_BAD_REQUEST, Status.get("param name missing"));
        return;/* w  w w .  j  a  v a  2s.  com*/
    }
    String skip = req.getParameter("skip");
    String limit = req.getParameter("limit");

    DB db = mongo.getDB(db_name);
    DBCollection col = db.getCollection(col_name);

    DBCursor c = col.find();
    if (c == null) {
        error(res, SC_NOT_FOUND, Status.get("no documents found"));
        return;
    }

    res.setIntHeader("X-Documents-Count", c.count());

    if (limit != null) {
        try {
            c.limit(Math.min(Integer.parseInt(limit), MAX_FIELDS_TO_RETURN));
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse limit"));
            c.close();
            return;
        }
    } else
        c.limit(MAX_FIELDS_TO_RETURN);

    if (skip != null) {
        try {
            c.skip(Integer.parseInt(skip));
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse skip"));
            c.close();
            return;
        }
    }

    StringBuilder buf = tl.get();
    buf.setLength(0);

    int no = 0;
    buf.append("[");
    while (c.hasNext()) {

        DBObject o = c.next();
        JSON.serialize(o, buf);
        buf.append(",");
        no++;

    }

    if (no > 0)
        buf.setCharAt(buf.length() - 1, ']');
    else
        buf.append(']');

    res.setIntHeader("X-Documents-Returned", no);

    out_str(req, buf.toString(), "application/json");

}

From source file:net.kamradtfamily.mongorest.QueryServlet.java

License:GNU General Public License

@Override
protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

    log.fine("doPost()");

    // server auth
    String ret;//from w w  w . ja v a2s  . co m

    InputStream is = req.getInputStream();
    String db_name = req.getParameter("dbname");
    String col_name = req.getParameter("colname");
    if (db_name == null || col_name == null) {
        String names[] = req2mongonames(req);
        if (names != null) {
            db_name = names[0];
            col_name = names[1];
        }
        if (db_name == null || col_name == null) {
            error(res, SC_BAD_REQUEST, Status.get("param name missing"));
            return;
        }
    }
    String skip = req.getParameter("skip");
    String limit = req.getParameter("limit");

    String _fields = req.getParameter("fields");
    String fields[] = null;
    if (_fields != null)
        fields = _fields.split("[,]");

    DB db = mongo.getDB(db_name);

    // mongo auth
    String user = req.getParameter("user");
    String passwd = req.getParameter("passwd");
    if (user != null && passwd != null && (!db.isAuthenticated())) {
        boolean auth = db.authenticate(user, passwd.toCharArray());
        if (!auth) {
            res.sendError(SC_UNAUTHORIZED);
            return;
        }
    }

    DBCollection col = db.getCollection(col_name);

    StringBuilder buf = tl.get();
    // reset buf
    buf.setLength(0);

    BufferedReader r = null;
    DBObject q = null, sort = null;

    try {

        r = new BufferedReader(new InputStreamReader(is));
        String data = r.readLine();
        if (data == null) {
            error(res, SC_BAD_REQUEST, Status.get("no data"));
            return;
        }
        try {
            q = (DBObject) JSON.parse(data);
            if (cache != null) {
                buf.append(db_name);
                buf.append(col_name);
                buf.append(data);
            }
        } catch (JSONParseException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse data"));
            return;
        }
        // sort param
        data = r.readLine();
        if (data != null) {
            try {
                sort = (DBObject) JSON.parse(data);
            } catch (JSONParseException e) {
                error(res, SC_BAD_REQUEST, Status.get("can not parse sort arg"));
                return;
            }
            if (cache != null)
                buf.append(data);
        }

    } finally {
        if (r != null)
            r.close();
    }

    // limit
    int lim;
    if (limit != null) {
        try {
            lim = Math.min(Integer.parseInt(limit), MAX_FIELDS_TO_RETURN);
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse limit"));
            return;
        }
    } else {
        lim = MAX_FIELDS_TO_RETURN;
    }
    if (cache != null) {
        buf.append(";limit=");
        buf.append(lim);
    }

    // skip
    int sk = -1;
    if (skip != null) {
        try {
            sk = Integer.parseInt(skip);
            if (cache != null) {
                buf.append(";skip=");
                buf.append(sk);
            }
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse skip"));
            return;
        }
    }

    // fields
    if (cache != null && _fields != null) {
        buf.append(";fields=");
        buf.append(_fields);
    }

    // from cache
    String cache_key = null;
    if (cache != null) {
        cache_key = buf.toString();
        try {
            ret = (String) cache.get(cache_key);
        }
        // some wrong char in key
        catch (IllegalArgumentException e) {
            int l = buf.length();
            for (int i = 0; i < l; i++) {
                if (buf.charAt(i) == ' ')
                    buf.setCharAt(i, '*');
            }
            cache_key = buf.toString();
            ret = (String) cache.get(cache_key);
        }
        if (ret != null) {
            out_str(req, ret, "application/json");
            return;
        }
    }

    // cursor
    DBCursor c;
    if (fields != null) {
        StringBuilder sb = new StringBuilder();
        sb.append("{");
        int len = fields.length;
        for (int i = 0; i < len; i++) {
            String s = fields[i];
            sb.append('"');
            sb.append(s);
            sb.append('"');
            sb.append(":1");
            if (i != (len - 1))
                sb.append(",");
        }
        sb.append("}");
        c = col.find(q, (DBObject) JSON.parse(sb.toString()));
    } else
        c = col.find(q);

    if (c == null || c.count() == 0) {
        error(res, SC_NOT_FOUND, Status.get("no documents found"));
        return;
    }

    if (sort != null)
        c.sort(sort);

    res.setIntHeader("X-Documents-Count", c.count());

    c.limit(lim);
    if (sk != -1)
        c.skip(sk);

    // reset buf
    buf.setLength(0);

    int no = 0;
    buf.append("[");
    while (c.hasNext()) {

        DBObject o = c.next();
        if (rm_id)
            o.removeField("_id");
        JSON.serialize(o, buf);
        buf.append(",");
        no++;

    }
    c.close();

    if (no > 0)
        buf.setCharAt(buf.length() - 1, ']');
    else
        buf.append(']');

    res.setIntHeader("X-Documents-Returned", no);

    ret = buf.toString();
    if (cache != null)
        cache.set(cache_key, ret);

    out_str(req, ret, "application/json");

}

From source file:net.kamradtfamily.mongorest.QueryServlet.java

License:GNU General Public License

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

    log.fine("doGet()");

    String db_name = req.getParameter("dbname");
    String col_name = req.getParameter("colname");
    if (db_name == null || col_name == null) {
        String names[] = req2mongonames(req);
        if (names != null) {
            db_name = names[0];//from www.j  a v a 2s.  c  om
            col_name = names[1];
        }
        if (db_name == null || col_name == null) {
            error(res, SC_BAD_REQUEST, Status.get("param name missing"));
            return;
        }
    }
    String skip = req.getParameter("skip");
    String limit = req.getParameter("limit");

    DB db = mongo.getDB(db_name);

    // mongo auth
    String user = req.getParameter("user");
    String passwd = req.getParameter("passwd");
    if (user != null && passwd != null && (!db.isAuthenticated())) {
        boolean auth = db.authenticate(user, passwd.toCharArray());
        if (!auth) {
            res.sendError(SC_UNAUTHORIZED);
            return;
        }
    }

    DBCollection col = db.getCollection(col_name);

    DBCursor c = col.find();
    if (c == null || c.count() == 0) {
        error(res, SC_NOT_FOUND, Status.get("no documents found"));
        return;
    }

    res.setIntHeader("X-Documents-Count", c.count());

    if (limit != null) {
        try {
            c.limit(Math.min(Integer.parseInt(limit), MAX_FIELDS_TO_RETURN));
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse limit"));
            c.close();
            return;
        }
    } else
        c.limit(MAX_FIELDS_TO_RETURN);

    if (skip != null) {
        try {
            c.skip(Integer.parseInt(skip));
        } catch (NumberFormatException e) {
            error(res, SC_BAD_REQUEST, Status.get("can not parse skip"));
            c.close();
            return;
        }
    }

    StringBuilder buf = tl.get();
    buf.setLength(0);

    int no = 0;
    buf.append("[");
    while (c.hasNext()) {

        DBObject o = c.next();
        if (rm_id)
            o.removeField("_id");
        JSON.serialize(o, buf);
        buf.append(",");
        no++;

    }
    c.close();

    if (no > 0)
        buf.setCharAt(buf.length() - 1, ']');
    else
        buf.append(']');

    res.setIntHeader("X-Documents-Returned", no);

    out_str(req, buf.toString(), "application/json");

}