substitute(sp, callback);
        sp.forEach(properties::setProperty);
    }

    public static void substitute(MavenProperties props, Function<String, String> callback) {
        for (Enumeration<?> e = props.propertyNames(); e.hasMoreElements(); ) {
            String name = (String) e.nextElement();
            String value = props.getProperty(name);
            if (value == null) {
                value = callback.apply(name);

     *
     * @return an enumeration of all the keys in this property list, including the keys in the default property list.
     */
    public Enumeration<?> propertyNames() {
        return Collections.enumeration(storage.keySet());
    }

    /**
     * Calls the map method put. Provided for parallelism with the getProperty method.

    ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();

    for (Enumeration<?> e = properties.propertyNames(); e.hasMoreElements(); ) {
      /*
       * requireNonNull is safe because propertyNames contains only non-null elements.
       *
       * Accordingly, we have it annotated as returning `Enumeration<? extends Object>` in our

    ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();

    for (Enumeration<?> e = properties.propertyNames(); e.hasMoreElements(); ) {
      /*
       * requireNonNull is safe because propertyNames contains only non-null elements.
       *
       * Accordingly, we have it annotated as returning `Enumeration<? extends Object>` in our

        rootLocaleFormat("%s must be inherited.", annotationClass),
        annotationClass.getAnnotation(Inherited.class));

    for (String propertyName : new String[] {"value", "absent"}) {
      Method method = null;
      try {
        method = annotationClass.getMethod(propertyName);
      } catch (NoSuchMethodException e) {
        throw new AssertionError("Annotation is missing required method", e);
      }

        rootLocaleFormat("%s must be inherited.", annotationClass),
        annotationClass.getAnnotation(Inherited.class));

    for (String propertyName : new String[] {"value", "absent"}) {
      Method method = null;
      try {
        method = annotationClass.getMethod(propertyName);
      } catch (NoSuchMethodException e) {
        throw new AssertionError("Annotation is missing required method", e);
      }

                Matcher matcher = EXPRESSION_PROJECT_NAME_PATTERN.matcher(s);
                while (matcher.find()) {
                    String propertyName = matcher.group(0);

                    if (path.startsWith("activation.file.") && "${project.basedir}".equals(propertyName)) {
                        continue;
                    }
                    addViolation(
                            problems,