[HOP-2141] NullPointerException raised on hop-server workflow start

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Cannot Reproduce
• Fix Version/s: Not applicable
• Component/s: Hop Server
• Environment: Windows 10, also tested on Linux (Ubuntu 20.04) with same results
• Assignee: Unassigned
• Reporter: Damir Lampa
• Created: 05/Nov/20 17:23
• Updated: 30/Jul/21 12:44
• Resolved: 26/Jul/21 15:29

Description

After submitting a simple workflow to hop-server (0.3 as well as 0.4 snapshot), I get the following in the hop-server console output:

 

===[Environment Settings - hop-server.bat]====================================
Java identified as java
HOP_OPTIONS=-Xmx2048m -DHOP_PLATFORM_OS=Windows -DHOP_PLATFORM_RUNTIME=GUI -debug

Command to start Hop will be:
java -classpath lib\*;libswt\win64\* -Djava.library.path=lib -Xmx2048m -DHOP_PLATFORM_OS=Windows -DHOP_PLATFORM_RUNTIME=GUI -debug org.apache.hop.www.HopServer 127.0.0.1 8080
===[Starting HopServer]=========================================================
2020/11/05 09:48:46 - HopServer - Installing timer to purge stale objects after 1440 minutes.
2020/11/05 09:48:47 - HopServer - Created listener for webserver @ address : 127.0.0.1:8080
2020/11/05 09:55:03 - testworkflow - Executing this workflow using the Remote Workflow Engine with run configuration 'Remote Workflow'
2020/11/05 09:55:04 - testworkflow - Executing this workflow using the Remote Workflow Engine with run configuration 'Remote Workflow'
2020/11/05 09:55:04 - ERROR: Error starting workflow
log4j:WARN No appenders could be found for logger (org.apache.hop).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
2020/11/05 09:55:04 - ERROR: org.apache.hop.core.exception.HopException:
2020/11/05 09:55:04 - There was an error starting the workflow on the remote server:
2020/11/05 09:55:04 - Unexpected error during workflow start: java.lang.NullPointerException at org.apache.hop.www.HopServerObjectEntry.hashCode(HopServerObjectEntry.java:61) at java.util.concurrent.ConcurrentHashMap.putVal(Unknown Source) at java.util.concurrent.ConcurrentHashMap.put(Unknown Source) at org.apache.hop.www.WorkflowMap.replaceWorkflow(WorkflowMap.java:66) at org.apache.hop.www.StartWorkflowServlet.doGet(StartWorkflowServlet.java:138) at javax.servlet.http.HttpServlet.service(HttpServlet.java:575) at javax.servlet.http.HttpServlet.service(HttpServlet.java:668) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:760) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:547) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1607) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1297) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:485) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1577) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1212) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:221) at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:59) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:501) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) at org.eclipse.jetty.server.Server.handle(Server.java:500) at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:383) at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:547) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:375) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:270) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103) at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:117) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:336) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:313) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:171) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:129) at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:388) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:806) at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:938) at java.lang.Thread.run(Unknown Source)
2020/11/05 09:55:04 -
2020/11/05 09:55:04 - at org.apache.hop.workflow.engines.remote.RemoteWorkflowEngine.sendToHopServer(RemoteWorkflowEngine.java:392)
2020/11/05 09:55:04 - at org.apache.hop.workflow.engines.remote.RemoteWorkflowEngine.startExecution(RemoteWorkflowEngine.java:259)
2020/11/05 09:55:04 - at org.apache.hop.www.StartWorkflowServlet.lambda$runWorkflow$0(StartWorkflowServlet.java:197)
2020/11/05 09:55:04 - at java.lang.Thread.run(Unknown Source)
2020/11/05 09:55:05 - 2020/11/05 09:55:04 - ERROR: Error starting workflow
2020/11/05 09:55:05 - 2020/11/05 09:55:04 - ERROR: org.apache.hop.core.exception.HopException:
2020/11/05 09:55:05 - 2020/11/05 09:55:04 - There was an error starting the workflow on the remote server:
2020/11/05 09:55:05 - 2020/11/05 09:55:04 - Unexpected error during workflow start: java.lang.NullPointerException

More details on the tests undertaken are attached.