int parallelism = DEFAULT_BUILDER_PARALLELISM;
            try {
                String str = request.getUserProperties().getProperty(BUILDER_PARALLELISM);
                if (str == null) {
                    str = request.getSystemProperties().getProperty(BUILDER_PARALLELISM);
                }
                if (str != null) {
                    parallelism = Integer.parseInt(str);
                }

  static final boolean GENERATE_CANCELLATION_CAUSES;

  static {
    // System.getProperty may throw if the security policy does not permit access.
    boolean generateCancellationCauses;
    try {
      generateCancellationCauses =
          Boolean.parseBoolean(
              System.getProperty("guava.concurrent.generate_cancellation_cause", "false"));
    } catch (SecurityException e) {

                Supplier<? extends Activation.Builder> creator, Activation.Builder builder, Activation target) {
            stk.push(nextFrame("property", Activation::getProperty));
            try {
                return super.transformActivation_Property(creator, builder, target);
            } finally {
                stk.pop();
            }
        }

        @Override