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Creating new request services

asked 2013-04-12 01:31:20 -0600

jforkey gravatar image

updated 2013-04-12 01:48:58 -0600

dornhege gravatar image

I am struggling with creating new requests dynamically. I have defined my own messages and I want to do something like request.setTask("xyz"); The request will happily take whatever I pass to it if I hardcode the tasks, but I want to have a separate function that I can call and will generate these responses. Do I need to create a ServiceManager and ServiceFactory?


final rosd_messages.RosDRequest request = serviceClient.newMessage();

works fine. However, what if we have another task "abc" that we want to execute? What if we aren't sure how many requests there will be? I can create a new request, but I can't initialize it to serviceClient.newMessage(); as the serviceClient is final.

Any help?

Thanks! James

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answered 2013-04-22 11:30:52 -0600

jforkey gravatar image

updated 2013-04-22 11:45:27 -0600

I've managed to achieve this by starting my third party application (where the requests derive from) in a separate thread then making the thread wait when you issue the request using:

synchronized (thread1) {

Then, wake it up in the onSuccess (and onFailure - don't want it getting stuck waiting) with:

  synchronized (thread1) {

Then I created a method to construct the requests that my third party client can call:

 public static void buildRequest(String str){

    final rosd_messages.RosDRequest req;
    req = node1.getServiceRequestMessageFactory().newFromType(rosd_messages.RosD._TYPE);
     ServiceClient<rosd_messages.RosDRequest, rosd_messages.RosDResponse> sClient;

    try {
        sClient = node1.newServiceClient("abc123", rosd_messages.RosD._TYPE);
      } catch (ServiceNotFoundException e) {
            throw new RosRuntimeException(e);

Note: There is no reason you have to use custom requests. I think this gives you the ability to build your own requests dynamically in a fairly efficient way. If you have a better idea, I am all ears.

Cheers! -James

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Asked: 2013-04-12 01:31:20 -0600

Seen: 261 times

Last updated: Apr 22 '13