public Builder setAttributes(
            com.google.devtools.cloudtrace.v2.Span.Attributes.Builder builderForValue) {
          if (attributesBuilder_ == null) {
            attributes_ = builderForValue.build();
          } else {
            attributesBuilder_.setMessage(builderForValue.build());
          }
          bitField0_ |= 0x00000002;
          onChanged();
          return this;
        }
<pre>
A set of attributes on the annotation. You can have up to 4 attributes
per Annotation.
</pre>

<code>.google.devtools.cloudtrace.v2.Span.Attributes attributes = 2;</code>
java-trace/proto-google-cloud-trace-v2/src/main/java/com/google/devtools/cloudtrace/v2/Span.java