* the new one. The result is a ConcurrentModificationException or other bad behavior.
         *
         * (If we decide that we really, really hate allocating two Iterators per cycle instead of
         * one, we can optimistically store the new Iterator and then be willing to throw it out if
         * the user calls remove().)
         */

        PrintStream olderr = System.err;

        final Set<String> realms;
        if (classWorld != null) {
            realms = new HashSet<>();
            for (ClassRealm realm : classWorld.getRealms()) {
                realms.add(realm.getId());
            }
        } else {
            realms = Collections.emptySet();
        }

        try {
            if (stdout != null) {

 * API</h2>
 *
 * <p>The successor to Guava's caching API is <a
 * href="https://github.com/ben-manes/caffeine/wiki">Caffeine</a>. Its API is designed to make it a
 * nearly drop-in replacement. Note that it is not available for Android or GWT/J2CL and that it may
 * have <a href="https://github.com/ben-manes/caffeine/wiki/Guava">different (usually better)

 * API</h2>
 *
 * <p>The successor to Guava's caching API is <a
 * href="https://github.com/ben-manes/caffeine/wiki">Caffeine</a>. Its API is designed to make it a
 * nearly drop-in replacement. Note that it is not available for Android or GWT/J2CL and that it may
 * have <a href="https://github.com/ben-manes/caffeine/wiki/Guava">different (usually better)

     * used by plugins.
     *
     * @return The project's class realm or {@code null}.
     */
    public ClassRealm getClassRealm() {
        return classRealm;
    }

    /**
     * Sets the artifact filter used to exclude shared extension artifacts from plugin realms. <strong>Warning:</strong>
     * This is an internal utility method that is only public for technical reasons, it is not part of the public API.