@java.lang.Override
    public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(jobName_)) {
        com.google.protobuf.GeneratedMessageV3.writeString(output, 1, jobName_);
      }
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(projectId_)) {
        com.google.protobuf.GeneratedMessageV3.writeString(output, 2, projectId_);
      }
      getUnknownFields().writeTo(output);
    }
<pre>
Required. The ID of the Google Cloud project that owns the
job.
</pre>

<code>string project_id = 2 [(.google.api.field_behavior) = REQUIRED];</code>

@return The bytes for projectId.
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferProto.java