Where can I get the SLE API about ccsds

[dariol83]

Hi @nculijun,

I will try to explain you the approach I used: if something is unclear, please let me know.

Inside the module eu.dariolucia.ccsds.sle.utl you have a folder containing all the ASN.1 SLE files. If you compare these files with the ones you find on CCSDS website, you will see that they are slightly different: the reason is due to the support to the different versions of the standard (from version 1 to version 5). When you compile the module with Maven, as part of the build process the ASN.1 files are parsed by the fantastic jASN1 compiler and Java classes are generated out of them (check inside the target folder, you will see those). These classes are then used by my library.

If you want to implement the provider side, you have three options:

1. Implement the Java class generation in your own module and use the generated classes to implement the provider side. In fact, the ASN.1 files that I use already define all the PDU and the structure to allow the implementation of the provider role. This is the most complex option, because it means that you have to implement everything almost from scratch.
2. Use the generated classes in module eu.dariolucia.ccsds.sle.utl, and implement the provider side with them: it is enough to have the eu.dariolucia.ccsds.sle.utl as dependency in your module, but still you have to implement the SLE provider classes yourself.
3. Use the already available provider classes in the eu.dariolucia.ccsds.sle.utl module. There are several unit tests that show how to instantiate, configure and use such classes.

Let me know what you want to do, and I can try to give you some hints.

Best regards,
Dario

[nculijun]

Hi Dario,
Thank you very much. I used the C++ API of SLE to implement the client side a few years ago, but now I need cross-platform support(windows and centos), so I am trying to use Java language to implement the client side and provider side of SLE, and I want to compare and test the program performance.

[dariol83]

I would recommend to start from the classes already defined in the eu.dariolucia.ccsds.sle.utl. You can have a look at the Readme.MD here: https://github.com/dariol83/ccsds/tree/master/eu.dariolucia.ccsds.sle.utl , the file explains how to create a provider role. If the supplied classes do not work OK for you, you can implement your own provider by using the generated ASN.1 classes, which are also part of the module.