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MD5 Checksum cannot be null

asked 2013-02-15 04:52:03 -0500

Srogacki gravatar image

I start up a subscriber on my android device to listen to a publisher running on my computer. I receive the following error after my subscriber has been created and executed:

E/SubscriberHandshakeHandler(3885): Subscriber handshake failed: Incoming MD5 checksum cannot be null.

I believe it occurs on receipt of the first message, but I am not sure.

I am running jellybean on the tablet and groovy on the pc. They are connected over a wifi connection with the roscore running on the pc.

Any help is appreciated!

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Are you using the latest rosjava? How is the publisher written? In Java as well?

damonkohler gravatar image damonkohler  ( 2013-02-19 10:34:13 -0500 )edit

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answered 2013-02-19 14:01:29 -0500

Srogacki gravatar image

I figured it out. I using a publisher with a custom-built message that was essentially serialized to a string, but still a custom-message in name. My subscriber was looking for std_msgs/String, but not receiving any, so the checksum was off.

Sorry for the confusion.


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Asked: 2013-02-15 04:52:03 -0500

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Last updated: Feb 19 '13