@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(mimeType_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 1, mimeType_);
    }
    if (!content_.isEmpty()) {
      output.writeBytes(2, content_);
    }
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(displayName_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 3, displayName_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Required. The file's display name.
</pre>

<code>string display_name = 3 [(.google.api.field_behavior) = REQUIRED];</code>

@return The bytes for displayName.
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/FileInputSource.java