@SuppressWarnings({"rawtypes"})
      protected com.google.protobuf.MapFieldReflectionAccessor internalGetMapFieldReflection(
          int number) {
        switch (number) {
          case 1:
            return internalGetAttributeMap();
          default:
            throw new RuntimeException("Invalid map field number: " + number);
        }
      }
<pre>
A set of attributes as key-value pairs.
</pre>

Protobuf type {@code google.devtools.cloudtrace.v2.Span.Attributes}
java-trace/proto-google-cloud-trace-v2/src/main/java/com/google/devtools/cloudtrace/v2/Span.java