code: public static void checkState(
        boolean expression, String errorMessageTemplate, Object... errorMessageArgs) {
      com.google.common.base.Preconditions.checkState(
          expression, errorMessageTemplate, errorMessageArgs);
    }
docs: Ensures the truth of an expression involving the state of the calling instance, but not
  involving any parameters to the calling method.
  
  @param expression a boolean expression
  @param errorMessageTemplate a template for the exception message should the check fail. The
  message is formed by replacing each {@code %s} placeholder in the template with an
  argument. These are matched by position - the first {@code %s} gets {@code
  errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
  square braces. Unmatched placeholders will be left as-is.
  @param errorMessageArgs the arguments to be substituted into the message template. Arguments
  are converted to strings using {@link String#valueOf(Object)}.
  @throws IllegalStateException if {@code expression} is false
  @throws NullPointerException if the check fails and either {@code errorMessageTemplate} or
  {@code errorMessageArgs} is null (don't let this happen)