[FLINK-1164] Uninformative error message when having an identity iteration with the Scala API

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.7.0-incubating
• Assignee: Stephan Ewen
• Reporter: Till Rohrmann
• Created: 13/Oct/14 22:31
• Updated: 18/Oct/14 17:48
• Resolved: 18/Oct/14 17:48

Description

If one implements an identity mapper with the Scala API, then one gets a strange error message which might be very confusing for the user:

Exception in thread "main" org.apache.flink.runtime.client.JobExecutionException: java.lang.Exception: Failed to deploy the task PartialSolution (BulkIteration (Bulk Iteration)) (1/8) - execution #0 to slot SubSlot 1 (0bbe935796159bfe18abca6f1b32769a (0) - ALLOCATED/ALIVE): java.lang.Exception: The number of writers created in 'registerInputOutput()' is different than the number of connected outgoing edges in the job graph.