Source:
<code>private void updateClientDetails(final Client client, String audience, String redirectURI, String logoutURI, String homeRealm) { if (!StringUtils.isEmpty(redirectURI)) { String[] allUris = redirectURI.trim().split(" "); List<String> redirectUris = new ArrayList<>(allUris.length); for (String uri : allUris) { if (!StringUtils.isEmpty(uri)) { if (!isValidURI(uri, false)) { throw new InvalidRegistrationException("An invalid redirect URI was specified: " + StringEscapeUtils.escapeHtml4(uri)); } redirectUris.add(uri); } } client.setRedirectUris(redirectUris); } else { <START> client.setRedirectUris(null); <END> } if (!StringUtils.isEmpty(logoutURI)) { String[] logoutUris = logoutURI.split(" "); for (String uri : logoutUris) { if (!isValidURI(uri, false)) { throw new InvalidRegistrationException("An invalid logout URI was specified: " + StringEscapeUtils.escapeHtml4(uri)); } } client.getProperties().put("post_logout_redirect_uris", logoutURI); } else { client.getProperties().remove("post_logout_redirect_uris"); } if (!StringUtils.isEmpty(audience)) { String[] auds = audience.trim().split(" "); List<String> registeredAuds = new ArrayList<>(auds.length); for (String aud : auds) { if (!StringUtils.isEmpty(aud)) { if (!isValidURI(aud, true)) { throw new InvalidRegistrationException("An invalid audience URI was specified: " + StringEscapeUtils.escapeHtml4(aud)); } registeredAuds.add(aud); } } client.setRegisteredAudiences(registeredAuds); } else { client.setRegisteredAudiences(null); } if (homeRealm != null) { client.setHomeRealm(homeRealm); if (homeRealms.containsKey(homeRealm)) { client.getProperties().put("homeRealmAlias", homeRealms.get(homeRealm)); } else { client.getProperties().remove("homeRealmAlias"); } } }</code><technical_language>Change null empty list here</technical_language>

Target:
private void updateClientDetails(final Client client, String audience, String redirectURI, String logoutURI, String homeRealm) { if (!StringUtils.isEmpty(redirectURI)) { String[] allUris = redirectURI.trim().split(" "); List<String> redirectUris = new ArrayList<>(allUris.length); for (String uri : allUris) { if (!StringUtils.isEmpty(uri)) { if (!isValidURI(uri, false)) { throw new InvalidRegistrationException("An invalid redirect URI was specified: " + StringEscapeUtils.escapeHtml4(uri)); } redirectUris.add(uri); } } client.setRedirectUris(redirectUris); } else { client.setRedirectUris(Collections.emptyList()); } if (!StringUtils.isEmpty(logoutURI)) { String[] logoutUris = logoutURI.split(" "); for (String uri : logoutUris) { if (!isValidURI(uri, false)) { throw new InvalidRegistrationException("An invalid logout URI was specified: " + StringEscapeUtils.escapeHtml4(uri)); } } client.getProperties().put("post_logout_redirect_uris", logoutURI); } else { client.getProperties().remove("post_logout_redirect_uris"); } if (!StringUtils.isEmpty(audience)) { String[] auds = audience.trim().split(" "); List<String> registeredAuds = new ArrayList<>(auds.length); for (String aud : auds) { if (!StringUtils.isEmpty(aud)) { if (!isValidURI(aud, true)) { throw new InvalidRegistrationException("An invalid audience URI was specified: " + StringEscapeUtils.escapeHtml4(aud)); } registeredAuds.add(aud); } } client.setRegisteredAudiences(registeredAuds); } else { client.setRegisteredAudiences(Collections.emptyList()); } if (homeRealm != null) { client.setHomeRealm(homeRealm); if (homeRealms.containsKey(homeRealm)) { client.getProperties().put("homeRealmAlias", homeRealms.get(homeRealm)); } else { client.getProperties().remove("homeRealmAlias"); } } }