Review fixes

dd-trace/src/main/java/datadog/trace/tracer/SpanImpl.java

@@ -4,7 +4,6 @@ import com.fasterxml.jackson.annotation.JsonAutoDetect;
 import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
 import com.fasterxml.jackson.annotation.JsonFormat;
 import com.fasterxml.jackson.annotation.JsonGetter;
-import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
@@ -215,7 +214,6 @@ class SpanImpl implements Span {
   }
 
   @Override
-  @JsonIgnore
   public synchronized Map<String, Object> getMeta() {
     return Collections.unmodifiableMap(meta);
   }

dd-trace/src/main/java/datadog/trace/tracer/Tracer.java

@@ -148,6 +148,8 @@ public class Tracer implements Closeable {
 
   @Override
   public void close() {
+    // FIXME: Handle the possibility of close being called more than once or not at all.
+    // FIXME: Depends on order of execution between finalize, GC, and the shutdown hook.
     writer.close();
   }
 

dd-trace/src/test/groovy/datadog/trace/tracer/TracerTest.groovy

@@ -45,6 +45,26 @@ class TracerTest extends Specification {
     0 * _  // don't allow any other interaction
   }
 
+  def "finalize closes writer"() {
+    setup:
+    def writer = Mock(Writer)
+    def tracer = Tracer.builder().writer(writer).build()
+
+    when:
+    tracer.finalize()
+
+    then: "closed writer"
+    1 * writer.close()
+    0 * _  // don't allow any other interaction
+
+    when:
+    tracer.finalize()
+
+    then: "thrown error swallowed"
+    1 * writer.close() >> { throw new Exception("test error") }
+    0 * _  // don't allow any other interaction
+  }
+
   def "test create current timestamp"() {
     setup:
     def tracer = Tracer.builder().config(config).build()