public Builder mergeAws(com.google.cloud.vmmigration.v1.AwsSourceDetails value) {
      if (awsBuilder_ == null) {
        if (sourceDetailsCase_ == 12
            && sourceDetails_
                != com.google.cloud.vmmigration.v1.AwsSourceDetails.getDefaultInstance()) {
          sourceDetails_ =
              com.google.cloud.vmmigration.v1.AwsSourceDetails.newBuilder(
                      (com.google.cloud.vmmigration.v1.AwsSourceDetails) sourceDetails_)
                  .mergeFrom(value)
                  .buildPartial();
        } else {
          sourceDetails_ = value;
        }
        onChanged();
      } else {
        if (sourceDetailsCase_ == 12) {
          awsBuilder_.mergeFrom(value);
        } else {
          awsBuilder_.setMessage(value);
        }
      }
      sourceDetailsCase_ = 12;
      return this;
    }
<pre>
AWS type source details.
</pre>

<code>.google.cloud.vmmigration.v1.AwsSourceDetails aws = 12;</code>
java-vmmigration/proto-google-cloud-vmmigration-v1/src/main/java/com/google/cloud/vmmigration/v1/Source.java