Add more null annotations (issue #359).

This commit adds some Nullable annotations that are required by the Checker
Framework, but it doesn't change any other code.  It also suppresses some Error
Prone and FindBugs warnings that conflict with the Checker Framework, since the
three tools use different algorithms.

1 files changed, 5 insertions, 5 deletions

diff --git a/impl_core/src/main/java/io/opencensus/implcore/trace/StartEndHandlerImpl.java b/impl_core/src/main/java/io/opencensus/implcore/trace/StartEndHandlerImpl.java
index fdb6147c..e22a86bd 100644
--- a/impl_core/src/main/java/io/opencensus/implcore/trace/StartEndHandlerImpl.java
+++ b/impl_core/src/main/java/io/opencensus/implcore/trace/StartEndHandlerImpl.java
@@ -33,8 +33,8 @@ import javax.annotation.concurrent.ThreadSafe;
 @ThreadSafe
 public final class StartEndHandlerImpl implements StartEndHandler {
   private final SpanExporterImpl spanExporter;
-  private final RunningSpanStoreImpl runningSpanStore;
-  private final SampledSpanStoreImpl sampledSpanStore;
+  @Nullable private final RunningSpanStoreImpl runningSpanStore;
+  @Nullable private final SampledSpanStoreImpl sampledSpanStore;
   private final EventQueue eventQueue;
   // true if any of (runningSpanStore OR sampledSpanStore) are different than null, which
   // means the spans with RECORD_EVENTS should be enqueued in the queue.
@@ -78,7 +78,7 @@ public final class StartEndHandlerImpl implements StartEndHandler {
   // An EventQueue entry that records the start of the span event.
   private static final class SpanStartEvent implements EventQueue.Entry {
     private final SpanImpl span;
-    private final RunningSpanStoreImpl activeSpansExporter;
+    @Nullable private final RunningSpanStoreImpl activeSpansExporter;
 
     SpanStartEvent(SpanImpl span, @Nullable RunningSpanStoreImpl activeSpansExporter) {
       this.span = span;
@@ -96,9 +96,9 @@ public final class StartEndHandlerImpl implements StartEndHandler {
   // An EventQueue entry that records the end of the span event.
   private static final class SpanEndEvent implements EventQueue.Entry {
     private final SpanImpl span;
-    private final RunningSpanStoreImpl runningSpanStore;
+    @Nullable private final RunningSpanStoreImpl runningSpanStore;
     private final SpanExporterImpl spanExporter;
-    private final SampledSpanStoreImpl sampledSpanStore;
+    @Nullable private final SampledSpanStoreImpl sampledSpanStore;
 
     SpanEndEvent(
         SpanImpl span,