Use the java backend code in Outsystems
Application Type
Service Studio Version
11.10.4 (Build 36716)

Hi All , 

1) Recently my organisation came to know about outsystems and they wanted our struts j2ee application UI to be redesigned in outsystems but the backend logic and the code that is in java needs to be the same. So how can I use the java logic/ import it into the outsystems where I will be redesigning the UI.

2) How can I connect the database that is in MSSQL to my outsystems UI.

Rank: #283


Question #1 : you can use existing backend logic, but you need to create REST API for it, so Outsystems can call those API. So far we cannot directly use existing java code into Outsystems.

Question#2 : this is simple, Outsystems already have configuration for connecting to external DB (see my screenshot). After you connect the external DB, you can use it like Outsystems Entity.


Rank: #395

Hi Phani,

Please refer below post to get more information.


Thanks & Kind Regards,


Rank: #283

Hi Sachin,

This is already not applicable for Outsystems version 11.


Rank: #2

Hi Phani,

First, OutSystems no longer directly supports Java. The Java backend is no longer available in the latest version of the Platform, version 11. The last version supporting Java was version 10, but this version is no longer supported.

Secondly, even if Java were supported, using existing code as-is in OutSystems wouldn't be possible. OutSystems generates Java (up to version 10) or .NET code from the OutSystems visual code. It is possible to include external code if it's in libraries through creating an Extension, but this is not encouraged and would still be quite some work if you have a lot of existing code.

As for your last question, connecting to an MSSQL database is easily possible. See here for more details.