saveLocationInfo error
com.mongodb.MongoSocketReadException: Prematurely reached end of stream
at com.mongodb.connection.socketStream.read(SocketStream.java:88)
at com.mongodb.connection.InternalStreamConnection.receiveResponseBuffers(InternalStreamConnection.java:494)
at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:224)
at com.mongodb.connection.CommandHelper.receiveReply(CommandHelper.java:134)
at com.mongodb.connection.CommandHelper.receiveCommandResult(CommandHelper.java:121)
at com.mongodb.connection.CommandHelper.executeCommand(CommandHelper.java:32)
at com.mongodb.connection.InternalStreamConnectionInitializer.initializeConnectionDescription(InternalStreamConnectionInitializer.java:85)
经检查发现maxConnectionIdleTime设置的时间太短，导致连接被关闭了。
