BlockingQueue and guard adding null

newrelic-agent/src/main/java/com/newrelic/agent/service/ServiceManagerImpl.java

@@ -10,7 +10,17 @@
 import com.newrelic.Function;
 import com.newrelic.InfiniteTracing;
 import com.newrelic.InfiniteTracingConfig;
-import com.newrelic.agent.*;
+import com.newrelic.agent.Agent;
+import com.newrelic.agent.AgentConnectionEstablishedListener;
+import com.newrelic.agent.ExpirationService;
+import com.newrelic.agent.GCService;
+import com.newrelic.agent.HarvestService;
+import com.newrelic.agent.HarvestServiceImpl;
+import com.newrelic.agent.RPMServiceManager;
+import com.newrelic.agent.RPMServiceManagerImpl;
+import com.newrelic.agent.ThreadService;
+import com.newrelic.agent.TracerService;
+import com.newrelic.agent.TransactionService;
 import com.newrelic.agent.attributes.AttributesService;
 import com.newrelic.agent.browser.BrowserService;
 import com.newrelic.agent.browser.BrowserServiceImpl;
@@ -43,9 +53,23 @@
 import com.newrelic.agent.samplers.NoopSamplerService;
 import com.newrelic.agent.samplers.SamplerService;
 import com.newrelic.agent.samplers.SamplerServiceImpl;
-import com.newrelic.agent.service.analytics.*;
+import com.newrelic.agent.service.analytics.InfiniteTracingEnabledCheck;
+import com.newrelic.agent.service.analytics.InsightsService;
+import com.newrelic.agent.service.analytics.InsightsServiceImpl;
+import com.newrelic.agent.service.analytics.SpanEventCreationDecider;
+import com.newrelic.agent.service.analytics.SpanEventsService;
+import com.newrelic.agent.service.analytics.TransactionDataToDistributedTraceIntrinsics;
+import com.newrelic.agent.service.analytics.TransactionEventsService;
 import com.newrelic.agent.service.async.AsyncTransactionService;
-import com.newrelic.agent.service.module.*;
+import com.newrelic.agent.service.module.JarAnalystFactory;
+import com.newrelic.agent.service.module.JarCollectorConnectionListener;
+import com.newrelic.agent.service.module.JarCollectorHarvestListener;
+import com.newrelic.agent.service.module.JarCollectorInputs;
+import com.newrelic.agent.service.module.JarCollectorService;
+import com.newrelic.agent.service.module.JarCollectorServiceImpl;
+import com.newrelic.agent.service.module.JarCollectorServiceProcessor;
+import com.newrelic.agent.service.module.JarData;
+import com.newrelic.agent.service.module.TrackedAddSet;
 import com.newrelic.agent.sql.SqlTraceService;
 import com.newrelic.agent.sql.SqlTraceServiceImpl;
 import com.newrelic.agent.stats.StatsEngine;
@@ -62,27 +86,28 @@
 import com.newrelic.api.agent.NewRelic;
 
 import java.net.URL;
-import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
+import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.logging.Level;
 
 /**
  * Service Manager implementation
- *
+ * <p>
  * This class is thread-safe.
  */
 public class ServiceManagerImpl extends AbstractService implements ServiceManager {
 
     private final ConcurrentMap<String, Service> services = new ConcurrentHashMap<>();
     private final CoreService coreService;
     private final ConfigService configService;
-
+    private final BlockingQueue<StatsWork> statsWork = new LinkedBlockingQueue<>();
     private volatile ExtensionService extensionService;
     private volatile ProfilerService profilerService;
     private volatile TracerService tracerService;
@@ -587,10 +612,34 @@ private void replayStartupStatsWork() {
         statsWork.clear();
     }
 
-    private final List<StatsWork> statsWork = new ArrayList<>();
+    @Override
+    public UtilizationService getUtilizationService() {
+        return utilizationService;
+    }
+
+    @Override
+    public DistributedTraceService getDistributedTraceService() {
+        return distributedTraceService;
+    }
+
+    @Override
+    public SpanEventsService getSpanEventsService() {
+        return spanEventsService;
+    }
+
+    @Override
+    public SourceLanguageService getSourceLanguageService() {
+        return sourceLanguageService;
+    }
+
+    @Override
+    public ExpirationService getExpirationService() {
+        return expirationService;
+    }
 
     private class InitialStatsService extends AbstractService implements StatsService {
         private final MetricAggregator metricAggregator = new StatsServiceMetricAggregator(this);
+        private final Logger initialStatsServiceLogger = Agent.LOG.getChildLogger("com.newrelic.InitialStatsService");
 
         protected InitialStatsService() {
             super("Bootstrap stats service");
@@ -603,7 +652,12 @@ public boolean isEnabled() {
 
         @Override
         public void doStatsWork(StatsWork statsWork) {
-            ServiceManagerImpl.this.statsWork.add(statsWork);
+            if (statsWork != null) {
+                ServiceManagerImpl.this.statsWork.add(statsWork);
+            } else {
+                initialStatsServiceLogger.log(Level.WARNING, "Problem adding a StatsWork to queue in InitialStatsService. StatsWork was null.");
+            }
+
         }
 
         @Override
@@ -625,29 +679,4 @@ public MetricAggregator getMetricAggregator() {
         }
     }
 
-    @Override
-    public UtilizationService getUtilizationService() {
-        return utilizationService;
-    }
-
-    @Override
-    public DistributedTraceService getDistributedTraceService() {
-        return distributedTraceService;
-    }
-
-    @Override
-    public SpanEventsService getSpanEventsService() {
-        return spanEventsService;
-    }
-
-    @Override
-    public SourceLanguageService getSourceLanguageService() {
-        return sourceLanguageService;
-    }
-
-    @Override
-    public ExpirationService getExpirationService() {
-        return expirationService;
-    }
-
 }