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[cm]

Hi Laurent,

when I run a node on windows (by startNode.bat) then I can see the output of the tasks which are running on this node in the cmd window.
On Linux I start the node with the JPPFNode wrapper. Is there a posibility to see or log the output of the tasks which are running in this node?
I need it for debugging.

Thanks
Christian

[lolo]

Hello CHristian,

I thought the node output was automatically logged in the wrapper's log file (wrapper-node.log file), isn't it the case?
If not, one possibiilty is to use a node initialization hook to redirect System.out and System.err to files, as follows:

Code: [Select]

public class OutputRedirectHook implements InitializationHook {
  @Override
  public void initializing(final UnmodifiableTypedProperties initialConfiguration) {
    try {
      PrintStream out = new PrintStream("stdout.log");
      PrintStream err = new PrintStream("stderr.log");
      System.setOut(out);
      System.setErr(err);
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}
Note that this will be a new feature in JPPF 4.1, which will allow you to specify the redirection directly from configuration properties. See JPPF-214 Ability to redirect std and err output for nodes and drivers for reference.

Sincerely,
-Laurent

[boris.klug]

Hi Christian,

here are my ideas for debugging the tasks:

1) Use a logging framework like log4j. With such a framework you can configure where the output should go: To a (local) file, to the client (using JMX, see the JPPF user manual) or even to a database.

2) Do no output at all: When an exception occurs, set the exception in the result and output/examin the exception in your client program. This is more for the normal operation of the program, not for debugging.