Build failed in Jenkins: NPanday-docs #6

[Apache Jenkins Server]

See <https://builds.apache.org/job/NPanday-docs/6/>

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Started by user brett
Building remotely on ubuntu4 in workspace 
<https://builds.apache.org/job/NPanday-docs/ws/>
Updating http://svn.apache.org/repos/asf/incubator/npanday/trunk
At revision 1302892
no change for http://svn.apache.org/repos/asf/incubator/npanday/trunk since the 
previous build
[NPanday-docs] $ mvn -f site/pom.xml 
-Dlocaldocs.folder=file://<https://builds.apache.org/job/NPanday-docs/ws/target/jenkins-site>
 -B -Plocal-docs site-deploy
FATAL: command execution failed
java.io.IOException: Cannot run program "mvn" (in directory 
"<https://builds.apache.org/job/NPanday-docs/ws/";)>: java.io.IOException: 
error=2, No such file or directory
        at java.lang.ProcessBuilder.start(ProcessBuilder.java:475)
        at hudson.Proc$LocalProc.<init>(Proc.java:244)
        at hudson.Proc$LocalProc.<init>(Proc.java:216)
        at hudson.Launcher$LocalLauncher.launch(Launcher.java:707)
        at hudson.Launcher$ProcStarter.start(Launcher.java:338)
        at hudson.Launcher$RemoteLaunchCallable.call(Launcher.java:932)
        at hudson.Launcher$RemoteLaunchCallable.call(Launcher.java:899)
        at hudson.remoting.UserRequest.perform(UserRequest.java:118)
        at hudson.remoting.UserRequest.perform(UserRequest.java:48)
        at hudson.remoting.Request$2.run(Request.java:287)
        at 
hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
        at java.util.concurrent.FutureTask.run(FutureTask.java:166)
        at 
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
        at 
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
        at java.lang.Thread.run(Thread.java:636)
Caused by: java.io.IOException: java.io.IOException: error=2, No such file or 
directory
        at java.lang.UNIXProcess.<init>(UNIXProcess.java:164)
        at java.lang.ProcessImpl.start(ProcessImpl.java:81)
        at java.lang.ProcessBuilder.start(ProcessBuilder.java:468)
        ... 15 more
Build step 'Invoke top-level Maven targets' marked build as failure