public UnframedGrpcErrorHandlerBuilder responseTypes(UnframedGrpcErrorResponseType... responseTypes) {
        requireNonNull(responseTypes, "responseTypes");

        if (this.responseTypes == null) {
            this.responseTypes = EnumSet.noneOf(UnframedGrpcErrorResponseType.class);
        }
        Collections.addAll(this.responseTypes, responseTypes);
        return this;
    }
Specifies the response types that the error handler will support.

<p>This method allows specifying one or more response types (e.g., JSON, PLAINTEXT)
that the error handler can produce. If nothing is specified or multiple types are specified, the actual
response type is determined by the response's content type.

@param responseTypes The response types to support
grpc/src/main/java/com/linecorp/armeria/server/grpc/UnframedGrpcErrorHandlerBuilder.java