Android Question How to run jRDC2 ?

SamuelP

Member
Licensed User
Hello,

I want to create a android app (using B4A) that communicates with my (public) sql-Server.

What I have already achieved:
- I set up a virtual machine with Windows 10 x64.
- I installed jdk and jre.
- I ran rdc using the RunRLC.bat
- I got a positives browser test (http://10.0.0.13:17178/test) from a other computer in the same network.
- Unfortunately I always got a "Job.Success = False" in my B4A-app.

- So I installed also B4J at the VM and ran the jRDC.b4j.
- I did same firewall and router settings ...
- and my B4A-app ist now working, also with public access: req.Initialize(Me, "http://80.121.142.217:17178/rdc")
- That's fine !!


Now my questions:
- What is the minimal need at a VM to let jRDC run?

- within the B4J-IDE I tried 'Project' --> 'Compile To Libary', but always got the error: 'Cannot access excluded module: main'. Is there no need to compile it and use it as a jar-file?

- Is there any way to make the querys more "open"? Or do I really have to predefine each query in the config.properties first?


Thanks for having created such a great thing. It seems B4A is what I have been looking for a long time.
Samuel
 
Hi Samuel,
the whole point of RDC (and similar) solution is to avoid the openness for security reason. No IT manager will let a DBMS exposed to the Internet and sending queries from your B4A app will be dangerous as well . This is the reason why you have to place them on the server and simply command their execution from the outside (mobile app); this way no "unexpected" DB command could be executed (e.g. DROP all tables).
Please search the Forum more on this topic since there are a lot of interesting hints on how to secure your installation.

udg
 
Last edited:
Upvote 0
Hi Samuel,
the whole point of RDC (and similar) solution is to avoid the openness for security reason. No IT manager will let a DBMS exposed to the Internet and sending queries from your B4A app will be dangerous as well . This is the reason why you have to place them on the server and simply command their execution from the outside (mobile app); this way no "unexpected" DB command could be executed (e.g. DROP all tables).
Please search the Forum more on this topic since there are a lot of interesting hints on how to secure your installation.

udg

That makes sense to me. Thanks for your answer.
 
Upvote 0
within the B4J-IDE I tried 'Project' --> 'Compile To Libary'
From within the B4j project jrdc2?

This is a mistake. To create the jar you just RUN the B4J project... F5
 
Upvote 0
From within the B4j project jrdc2?

This is a mistake. To create the jar you just RUN the B4J project... F5

I have a B4J-Project (that one, that I could download in this forum; and adapt to my needs) and what to compile a jar-file, so that I can run it at a server.
When I use F5 within the b4j-IDE, i can't find any changed jar-file at my hdd.
So please, can you say me where I can find the compiled jar, or what is the right way to create it?
 
Upvote 0
That was the first path I was looking for it. :-)
But it is empty!

I opened "d:\Downloads\jRDC\jRDC.b4j", ran it, test it (it's working), but "d:\Downloads\jRDC\Objects\" stays empty.
 
Upvote 0
but "d:\Downloads\jRDC\Objects\" stays empty.
i never encountered such a issue.

I just downloaded jrdc, extract, run (F5).

B4J version: 5.50 BETA #2
Parsing code. (0.01s)
Compiling code. (0.04s)
Compiling layouts code. (0.00s)
Organizing libraries. (0.00s)
Compiling generated Java code. (4.37s)
Building jar file. (1.47s)
Jar file created: E:\B4J\Projekte\jRDC\Objects\jRDC.jar
Running application. (0.68s)
Completed successfully.

And the file E:\B4J\Projekte\jRDC\Objects\jRDC.jar is there...
 
Upvote 0
Back
Top