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.sun.sgs.service.store.db.DbCursor

      int result;
      byte[] hashValue = classesDb.get(dbTxn, hashKey, false);
      if (hashValue != null) {
    result = DataEncoding.decodeInt(hashValue);
      } else {
    DbCursor cursor = classesDb.openCursor(dbTxn);
    try {
        result = cursor.findLast()
      ? getClassIdFromKey(cursor.getKey()) + 1 : 1; 
        byte[] idKey = getKeyFromClassId(result);
        boolean success =
      cursor.putNoOverwrite(idKey, classInfo);
        if (!success) {
      throw new DataStoreException(
          "Class ID key already present");
        }
    } finally {
        cursor.close();
    }
    boolean success = classesDb.putNoOverwrite(
        dbTxn, hashKey, DataEncoding.encodeInt(result));
    if (!success) {
        throw new DataStoreException(

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

     * @param  oid the object ID or -1
     * @return  the next object ID or -1
     */
    long nextObjectIdRaw(Transaction txn, long oid) {
  TxnInfo txnInfo = checkTxn(txn);
  DbCursor cursor = oidsDb.openCursor(txnInfo.dbTxn);
  try {
      boolean found =  (oid < 0)
    ? cursor.findFirst()
    : cursor.findNext(DataEncoding.encodeLong(oid + 1));
      if (found) {
    return DataEncoding.decodeLong(cursor.getKey());
      } else {
    return -1;
      }
  } finally {
      cursor.close();
  }
    }

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