我在java中为dbcursor设置了’notimeout’选项:
BasicDBObject nearbyQueries = new BasicDBObject("$gt", 0)
.append("$lte", 2);
DBCursor trueClassInstances = locationsCollection.find(new BasicDBObject("distanceFromHotel", nearbyQueries)).addOption(Bytes.QUERYOPTION_NOTIMEOUT).limit(100000);
double counter = 0;
int currentPresent = 0;
for (DBObject instance : trueClassInstances) {
...
}
即使我设置了此选项,也会抛出此异常:
Exception in thread "main" com.mongodb.MongoCursorNotFoundException: Query Failed with error code -5 and error message 'Cursor 1876954464377 not found on server XXXXXX:27017' on server XXXXXXXX:27017
at com.mongodb.connection.GetMoreProtocol.receiveMessage(GetMoreProtocol.java:115)
at com.mongodb.connection.GetMoreProtocol.execute(GetMoreProtocol.java:68)
at com.mongodb.connection.GetMoreProtocol.execute(GetMoreProtocol.java:37)
at com.mongodb.connection.DefaultServer$DefaultServerProtocolExecutor.execute(DefaultServer.java:155)
at com.mongodb.connection.DefaultServerConnection.executeProtocol(DefaultServerConnection.java:219)
at com.mongodb.connection.DefaultServerConnection.getMore(DefaultServerConnection.java:194)
at com.mongodb.operation.QueryBatchCursor.getMore(QueryBatchCursor.java:197)
at com.mongodb.operation.QueryBatchCursor.hasNext(QueryBatchCursor.java:93)
at com.mongodb.MongoBatchCursorAdapter.hasNext(MongoBatchCursorAdapter.java:46)
at com.mongodb.DBCursor.hasNext(DBCursor.java:152)
at locationExtraction.distanceClassification.FeatureAnalyzer.main(FeatureAnalyzer.java:27)
FeatureAnalyzer.java:27是for循环行.
此问题出现在具有类似设置的其他项目中…
我究竟做错了什么?也许我选择’for’循环而不是这种迭代会导致这种奇怪的行为?
while(cursor.hasNext())
{
DBObject next = cursor.next();
}
谢谢
解决方法:
看起来您无法在时间限制内处理每个批次.尝试减少批量大小,以便在时间用完之前消耗每批次.这应该有所帮助.
cursor.addOption(com.mongodb.Bytes.QUERYOPTION_NOTIMEOUT).batchSize(100)