in geronimo-openapi-impl/src/main/java/org/apache/geronimo/microprofile/openapi/impl/model/ComponentsImpl.java [153:158]
public Components addHeader(final String key, final Header _headers) {
if (_headers != null) {
(this._headers = this._headers == null ? new LinkedHashMap<>() : this._headers).put(key, _headers);
}
return this;
}