diff --git a/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/JobCollector.java b/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/JobCollector.java
index f72f6db..63e5de1 100644
--- a/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/JobCollector.java
+++ b/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/JobCollector.java
@@ -5,6 +5,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 import java.util.stream.Collectors;
 
@@ -48,7 +49,7 @@ public Map<PluginWrapper, JobsPerPlugin> getJobsPerPlugin()
                     }
                 }
             } catch(Exception e){
-                LOGGER.warning("Exception caught: " + e );
+                LOGGER.log(Level.WARNING, "Exception caught: " + e , e);
             }
         }
 
@@ -68,9 +69,9 @@ public Map<PluginWrapper, JobsPerPlugin> getJobsPerPlugin()
                         addItem(item, plugin);
                     }
                 } catch(Exception e){
-                    LOGGER.warning("Exception caught in job " + item.getFullName() + ": " + e );
+                    LOGGER.log(Level.WARNING, "Exception caught in job " + item.getFullName() + ": " + e , e);
                 } catch (Throwable e){
-                    LOGGER.severe("Exception caught in job " + item.getFullName() + ": " + e );
+                    LOGGER.log(Level.SEVERE,"Exception caught in job " + item.getFullName() + ": " + e, e);
                 }
             }
         }
diff --git a/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/PipelineLastBuildAnalyzer.java b/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/PipelineLastBuildAnalyzer.java
index 604e1a2..3e660bc 100644
--- a/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/PipelineLastBuildAnalyzer.java
+++ b/src/main/java/org/jenkinsci/plugins/pluginusage/analyzer/PipelineLastBuildAnalyzer.java
@@ -98,7 +98,9 @@ private void coreStepProcess(Set<PluginWrapper> plugins, FlowNode f) {
             if (describable != null) {
                 final Descriptor<?> descriptor = SymbolLookup.get()
                         .findDescriptor(Describable.class, describable.getSymbol());
-                plugins.add(getPluginFromClass(descriptor.clazz));
+                if (descriptor != null){
+                    plugins.add(getPluginFromClass(descriptor.clazz));
+                }
             }
         }
     }