When a GET/PUT/POST operations includes queryParams, then the feign generator wrongly generates the Basename instead of the paramName. That leads to
a java.illegalstateException ("Body parameters cannot be used with form parameters") in Feign Contract when attempting to invoke the Method.
i.e: a generated feign client:
public interface PersonClientTest extends RestApi {
@RequestLine("GET /personen/{kundenNummer}?mitUnterstruktur={mitUnterstruktur}")
@headers({
"Accept: application/json",
"If-None-Match: {ifNoneMatch}"
})
PersonOut getPersonByKundenNummer(@param(value="kundenNummer", expander=ParamExpander.class) String kundenNummer, @param(value="If-None-Match", expander=ParamExpander.class) String ifNoneMatch, @param(value="mitUnterstruktur", expander=ParamExpander.class) Boolean mitUnterstruktur);
}

in the headers:
"If-None-Match: {ifNoneMatch}"
but in the method:
@param(value="If-None-Match", expander=ParamExpander.class) String ifNoneMatch
the value should be ifNoneMatch instead of "If-None-Match"

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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

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