spring-hateoas-ext/src/main/java/de/escalon/hypermedia/spring/SpringActionInputParameter.java
public boolean isRequired() {
        boolean ret;
        if (isRequestBody()) {
            ret = requestBody.required();
        } else if (isRequestParam()) {
            ret = !(isDefined(requestParam.defaultValue()) || !requestParam.required());
        } else if (isRequestHeader()) {
            ret = !(isDefined(requestHeader.defaultValue()) || !requestHeader.required());
        } else {
            ret = true;
        }
        return ret;
    }
public boolean isRequired() {
        boolean ret;
        if (isRequestBody()) {
            ret = requestBody.required();
        } else if (isRequestParam()) {
            ret = !(isDefined(requestParam.defaultValue()) || !requestParam.required());
        } else if (isRequestHeader()) {
            ret = !(isDefined(requestHeader.defaultValue()) || !requestHeader.required());
        } else {
            ret = true;
        }
        return ret;
    }
Is this action input parameter required, based on the presence of a default value, the parameter annotations and
the kind of input parameter.

@return true if required