public Builder mergeMetadata(com.google.cloud.talent.v4.ResponseMetadata value) {
      if (metadataBuilder_ == null) {
        if (((bitField0_ & 0x00000004) != 0)
            && metadata_ != null
            && metadata_ != com.google.cloud.talent.v4.ResponseMetadata.getDefaultInstance()) {
          getMetadataBuilder().mergeFrom(value);
        } else {
          metadata_ = value;
        }
      } else {
        metadataBuilder_.mergeFrom(value);
      }
      if (metadata_ != null) {
        bitField0_ |= 0x00000004;
        onChanged();
      }
      return this;
    }
<pre>
Additional information for the API invocation, such as the request
tracking id.
</pre>

<code>.google.cloud.talent.v4.ResponseMetadata metadata = 3;</code>
java-talent/proto-google-cloud-talent-v4/src/main/java/com/google/cloud/talent/v4/ListCompaniesResponse.java