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2012-12-17 08:46:01 -0600 commented question How to get publisher info from a message?

Thanks for the two suggestions, tfoote. I haven't had any success getting the remapping feature working, so that may be another short-coming of the Java JNI wrappers I'm using. Been thinking about switching to the full Java core implementation and it looks like it's time. Appreciate your help with both of my recent questions. :)

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2012-12-17 08:30:31 -0600 commented question Are there ROS API documents published, and where?

Ah, I see where I went wrong - I started drilling down from the link in the main page, under the section "3. API Reference", and assumed that the link in the top right box for "Package Links" would be the same. Thanks for your patience and quick responses, dornhege and tfoote.

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2012-12-16 21:51:44 -0600 asked a question Are there ROS API documents published, and where?

This seems like a stupid question, but I have honestly tried and failed to find any documentation for the ROS APIs. To better clarify, I'm coming from the Java world, where I can go to Oracle's website and look up the API for any class that's in the standard libraries. Not that I'm asking for the same level of documentation, but it seems like there should be something similar and it's just my failure in finding it. Or do I need to get the source code for the particular library I'm wondering about and reference those files directly?

I just posted previous question that I should have been able to answer for myself if I could have located the API documentation for the roscpp library. Can someone please point me in the right direction?

Thanks! Hung

2012-12-16 21:31:57 -0600 asked a question How to get publisher info from a message?

Can anyone tell me if it's possible to get publisher information in the callback of a particular message?

For the system I'm trying to setup, I've implemented a node that publishes odometry messages (type: nav_msgs/Odometry) and am using a launch file to start multiple instances of this node, under different name spaces. Another node type (call it the coordinator node) will listen for the odometry messages from the multiple publishers. The point of the coordinator node is that it will coordinate the movement of multiple robots based on their reported locations. I'm new to ROS, so I've started by implementing my nodes using the basic templates shown in the tutorials, but I'm now realizing that the example callback method doesn't allow for identifying which particular node broadcasted a given message.

For now, I'm programming in Java and using the client_rosjava_jni library. I was hoping there would be another callback class that would include the publisher info, along with the published message, but I'm not seeing that option, at least in the JNI wrappers. I can imagine getting around this by making my first node type publish a custom message type that includes the pedigree information along with the basic odometry message type, but it seems like this should already be available in the core system. Does anyone know if that's true? Am I not seeing this option because I'm using the JNI wrappers?

Thanks in advance for any help-suggestions.


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2012-11-02 08:40:08 -0600 commented question fatal: unable to connect to

Thanks for the help, Lorenz! You're probably correct that my company's firewall is the cause of the problem. I installed from the debian packages as you suggested and it worked. I'm new to the ROS world and it's great to have help like this. :)

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2012-11-01 09:50:07 -0600 asked a question fatal: unable to connect to

Hi Everyone, I'm trying to install the JNI version of rosjava, and am getting connection failure. Anyone have an idea what's going on with the host site? I've tried three different ways: git, git via rosws set, and sudo. I don't know why the sudo approach failed, but I'm guessing it might the same connection issue. Thanks in advance for any help offered. My steps and terminal output are below.

hq@ubuntu:/opt/ros/fuerte$ roscd
hq@ubuntu:~/fuerte_workspace$ ls
hq@ubuntu:~/fuerte_workspace$ git clone -b cturtle_released git:// client_rosjava
Cloning into 'client_rosjava'...
fatal: unable to connect to[0:]: errno=Connection timed out

hq@ubuntu:~/fuerte_workspace$ rosws set client_rosjava --git  git://

     Add new elements:
  client_rosjava    git  git://   

Continue: (y)es, (n)o: y
Overwriting /home/hq/fuerte_workspace/.rosinstall

Do not forget to do ...
$ source /home/hq/fuerte_workspace/
... in every open terminal.
Config changed, remember to run 'rosws update client_rosjava' to update the folder from git
hq@ubuntu:~/fuerte_workspace$ rosws update client_rosjava
[client_rosjava] Installing git:// (version None) to /home/hq/fuerte_workspace/client_rosjava
WARNING [vcstools] Command failed: 'git clone --recursive git:// /home/hq/fuerte_workspace/client_rosjava'
 errcode: 128:
fatal: unable to connect to[0:]: errno=Connection timed out

Exception caught during install: Error processing 'client_rosjava' : [client_rosjava] Checkout of git:// version None into /home/hq/fuerte_workspace/client_rosjava failed.

ERROR: Error processing 'client_rosjava' : [client_rosjava] Checkout of git:// version None into /home/hq/fuerte_workspace/client_rosjava failed.

hq@ubuntu:~/fuerte_workspace$ sudo apt-get install ros-fuerte-rosjava-jni
[sudo] password for hq: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package ros-fuerte-rosjava-jni