private SimpleImmutableEntry<String, String> splitQueryParameter(String pair) {
    int eq = pair.indexOf("=");
    final String name = (eq > 0) ? pair.substring(0, eq) : pair;
    final String value = (eq > 0 && eq < pair.length()) ? pair.substring(eq + 1) : null;
    return new SimpleImmutableEntry<>(name, value);
  }
The Query String for the template. Expressions are not resolved.

@return the Query String.
core/src/main/java/feign/RequestTemplate.java