Examples of com.massivecraft.mcore.xlib.mongodb.DBCursor

Package com.massivecraft.mcore.xlib.mongodb

Examples of com.massivecraft.mcore.xlib.mongodb.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

     * @throws MongoException 
     */
    public List<GridFSDBFile> find( DBObject query , DBObject sort){
        List<GridFSDBFile> files = new ArrayList<GridFSDBFile>();


        DBCursor c = null;
        try {
            c = _filesCollection.find( query );
            if (sort != null) {
                c.sort(sort);
            }
            while ( c.hasNext() ){
                files.add( _fix( c.next() ) );
            }
        } finally {
             if (c != null){
                 c.close();
             }
        }
        return files;
    }

View Full Code Here

  
  @Override
  public boolean containsId(Coll<?> coll, String id)
  {
    DBCollection dbcoll = fixColl(coll);
    DBCursor cursor = dbcoll.find(new BasicDBObject(ID_FIELD, id));
    return cursor.count() != 0;
  }

View Full Code Here

  {
    List<String> ret = null;
    
    DBCollection dbcoll = fixColl(coll);
    
    DBCursor cursor = dbcoll.find(dboEmpty, dboKeysId);
    try
    {
      ret = new ArrayList<String>(cursor.count());
      while(cursor.hasNext())
      {
        Object remoteId = cursor.next().get(ID_FIELD);
        ret.add(remoteId.toString());
      }
    }
    finally
    {
      cursor.close();
    }
    
    return ret;
  }

View Full Code Here

  {
    Map<String, Long> ret = null;
    
    DBCollection dbcoll = fixColl(coll);
    
    DBCursor cursor = dbcoll.find(dboEmpty, dboKeysIdandMtime);
    try
    {
      ret = new HashMap<String, Long>(cursor.count());
      while(cursor.hasNext())
      {
        BasicDBObject raw = (BasicDBObject)cursor.next();
        Object remoteId = raw.get(ID_FIELD);
        if ( ! raw.containsField(MTIME_FIELD)) continue; // This should not happen! But better to ignore than crash?
        Long mtime = raw.getLong(MTIME_FIELD);
        ret.put(remoteId.toString(), mtime);
      }
    }
    finally
    {
      cursor.close();
    }
    
    return ret;
  }

View Full Code Here

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Related Classes of com.massivecraft.mcore.xlib.mongodb.DBCursor

com.massivecraft.mcore.store.DriverMongo

com.massivecraft.mcore.xlib.mongodb.gridfs.GridFS

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