2016-09-14 04:59:50,035 SEVERE [hudson.triggers.SafeTimerTask] (jenkins.util.Timer [#8]) Timer task hudson.slaves.NodeProvisioner$NodeProvisionerInvoker@77be2155 failed
java.lang.NullPointerException
        at com.redhat.foreman.ForemanSharedNodeCloud.canProvision(ForemanSharedNodeCloud.java:155)
        at hudson.slaves.NodeProvisioner$StandardStrategyImpl.apply(NodeProvisioner.java:661)
        at hudson.slaves.NodeProvisioner.update(NodeProvisioner.java:286)
        at hudson.slaves.NodeProvisioner.access$000(NodeProvisioner.java:57)
        at hudson.slaves.NodeProvisioner$NodeProvisionerInvoker.doRun(NodeProvisioner.java:775)
        at hudson.triggers.SafeTimerTask.run(SafeTimerTask.java:51)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
        at java.util.concurrent.FutureTask$Sync.innerRunAndReset(FutureTask.java:317)
        at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:150)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$101(ScheduledThreadPoolExecutor.java:98)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.runPeriodic(ScheduledThreadPoolExecutor.java:180)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:204)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
        at java.lang.Thread.run(Thread.java:682)

    @Override
    public boolean canProvision(Label label) {
        Map<String, String> hostsMap = getForemanAPI().getCompatibleHosts();
        Set<String> hosts = hostsMap.keySet();
        for (String host: hosts) {
            boolean match = label.matches(Label.parse(hostsMap.get(host)));
            if (match) {
                    return true;
            }
        }
        return false;
    }

boolean match = label.matches(Label.parse(hostsMap.get(host)));