Java "resteasy" ApiClient not adding default HTTP headers correctly

Description

In the ApiClient.java file around line 592 the following code is responsible for adding the default http headers to the request.

for (Entry<String, String> defaultHeaderEnrty: defaultHeaderMap.entrySet()) {
  if (!headerParams.containsKey(defaultHeaderEnrty.getKey())) {
    String value = defaultHeaderEnrty.getKey();
    if (value != null) {
      invocationBuilder = invocationBuilder.header(defaultHeaderEnrty.getKey(), value);
    }
  }
}

The line "String value = defaultHeaderEnrty.getKey();" is wrong and should have been "String value = defaultHeaderEnrty.getValue();"

Swagger-codegen version

2.3.1

Open ApiClient.java around line 592 and inspect how defaultHeaderMap entries are used when building the request. Confirm the header value comes from each entry's value rather than its key, then verify that generated resteasy clients send configured default HTTP headers correctly.