Java FTPS クライアントでの TLS セッション再利用の問題を解決するにはどうすればよいですか?

@Override
protected void _prepareDataSocket_(final Socket socket) {
    if (preferences.getBoolean("ftp.tls.session.requirereuse")) {
        if (socket instanceof SSLSocket) {
            // Control socket is SSL
            final SSLSession session = ((SSLSocket) _socket_).getSession();
            if (session.isValid()) {
                final SSLSessionContext context = session.getSessionContext();
                context.setSessionCacheSize(preferences.getInteger("ftp.ssl.session.cache.size"));
                try {
                    final Field sessionHostPortCache = context.getClass().getDeclaredField("sessionHostPortCache");
                    sessionHostPortCache.setAccessible(true);
                    final Object cache = sessionHostPortCache.get(context);
                    final Method putMethod = cache.getClass().getDeclaredMethod("put", Object.class, Object.class);
                    putMethod.setAccessible(true);
                    Method getHostMethod;
                    try {
                        getHostMethod = socket.getClass().getMethod("getPeerHost");
                    } catch (NoSuchMethodException e) {
                        // Running in IKVM
                        getHostMethod = socket.getClass().getDeclaredMethod("getHost");
                    }
                    getHostMethod.setAccessible(true);
                    Object peerHost = getHostMethod.invoke(socket);
                    putMethod.invoke(cache, String.format("%s:%s", peerHost, socket.getPort()).toLowerCase(Locale.ROOT), session);
                } catch (NoSuchFieldException e) {
                    // Not running in expected JRE
                    log.warn("No field sessionHostPortCache in SSLSessionContext", e);
                } catch (Exception e) {
                    // Not running in expected JRE
                    log.warn(e.getMessage());
                }
            } else {
                log.warn(String.format("SSL session %s for socket %s is not rejoinable", session, socket));
            }
        }
    }
}