/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.ranger.ldapusersync.process; import java.util.ArrayList; import java.util.Arrays; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Properties; import java.util.Set; import java.util.StringTokenizer; import javax.naming.Context; import javax.naming.InvalidNameException; import javax.naming.NamingEnumeration; import javax.naming.directory.Attribute; import javax.naming.directory.Attributes; import javax.naming.directory.SearchControls; import javax.naming.directory.SearchResult; import javax.naming.ldap.Control; import javax.naming.ldap.InitialLdapContext; import javax.naming.ldap.LdapContext; import javax.naming.ldap.PagedResultsControl; import javax.naming.ldap.PagedResultsResponseControl; import javax.naming.ldap.StartTlsRequest; import javax.naming.ldap.StartTlsResponse; import org.apache.log4j.Logger; import org.apache.ranger.unixusersync.config.UserGroupSyncConfig; import org.apache.ranger.usergroupsync.AbstractUserGroupSource; import org.apache.ranger.usergroupsync.UserGroupSink; public class LdapUserGroupBuilder extends AbstractUserGroupSource { private static final Logger LOG = Logger.getLogger(LdapUserGroupBuilder.class); private static final int PAGE_SIZE = 500; private String ldapUrl; private String ldapBindDn; private String ldapBindPassword; private String ldapAuthenticationMechanism; private String ldapReferral; private String searchBase; private String[] userSearchBase; private String userNameAttribute; private int userSearchScope; private String userObjectClass; private String userSearchFilter; private String extendedUserSearchFilter; private SearchControls userSearchControls; private Set<String> userGroupNameAttributeSet; private boolean pagedResultsEnabled = true; private int pagedResultsSize = 500; private boolean groupSearchFirstEnabled; private boolean userSearchEnabled; private boolean groupSearchEnabled = true; private String[] groupSearchBase; private int groupSearchScope; private String groupObjectClass; private String groupSearchFilter; private String extendedGroupSearchFilter; private String extendedAllGroupsSearchFilter; private SearchControls groupSearchControls; private String groupMemberAttributeName; private String groupNameAttribute; private LdapContext ldapContext; private StartTlsResponse tls; private boolean userNameCaseConversionFlag; private boolean groupNameCaseConversionFlag; private boolean userNameLowerCaseFlag; private boolean groupNameLowerCaseFlag; private boolean groupUserMapSyncEnabled; private Map<String, UserInfo> userGroupMap; public static void main(String[] args) throws Throwable { LdapUserGroupBuilder ugBuilder = new LdapUserGroupBuilder(); ugBuilder.init(); } public LdapUserGroupBuilder() { super(); LOG.info("LdapUserGroupBuilder created"); String userNameCaseConversion = config.getUserNameCaseConversion(); if (UserGroupSyncConfig.UGSYNC_NONE_CASE_CONVERSION_VALUE.equalsIgnoreCase(userNameCaseConversion)) { userNameCaseConversionFlag = false; } else { userNameCaseConversionFlag = true; userNameLowerCaseFlag = UserGroupSyncConfig.UGSYNC_LOWER_CASE_CONVERSION_VALUE.equalsIgnoreCase(userNameCaseConversion); } String groupNameCaseConversion = config.getGroupNameCaseConversion(); if (UserGroupSyncConfig.UGSYNC_NONE_CASE_CONVERSION_VALUE.equalsIgnoreCase(groupNameCaseConversion)) { groupNameCaseConversionFlag = false; } else { groupNameCaseConversionFlag = true; groupNameLowerCaseFlag = UserGroupSyncConfig.UGSYNC_LOWER_CASE_CONVERSION_VALUE.equalsIgnoreCase(groupNameCaseConversion); } } @Override public void init() throws Throwable{ setConfig(); } private void createLdapContext() throws Throwable { Properties env = new Properties(); env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory"); env.put(Context.PROVIDER_URL, ldapUrl); if (ldapUrl.startsWith("ldaps") && (config.getSSLTrustStorePath() != null && !config.getSSLTrustStorePath().trim().isEmpty())) { env.put("java.naming.ldap.factory.socket", "org.apache.ranger.ldapusersync.process.CustomSSLSocketFactory"); } ldapContext = new InitialLdapContext(env, null); if (!ldapUrl.startsWith("ldaps")) { if (config.isStartTlsEnabled()) { tls = (StartTlsResponse) ldapContext.extendedOperation(new StartTlsRequest()); if (config.getSSLTrustStorePath() != null && !config.getSSLTrustStorePath().trim().isEmpty()) { tls.negotiate(CustomSSLSocketFactory.getDefault()); } else { tls.negotiate(); } LOG.info("Starting TLS session..."); } } ldapContext.addToEnvironment(Context.SECURITY_PRINCIPAL, ldapBindDn); ldapContext.addToEnvironment(Context.SECURITY_CREDENTIALS, ldapBindPassword); ldapContext.addToEnvironment(Context.SECURITY_AUTHENTICATION, ldapAuthenticationMechanism); ldapContext.addToEnvironment(Context.REFERRAL, ldapReferral); } private void setConfig() throws Throwable { LOG.info("LdapUserGroupBuilder initialization started"); groupSearchFirstEnabled = config.isGroupSearchFirstEnabled(); userSearchEnabled = config.isUserSearchEnabled(); groupSearchEnabled = config.isGroupSearchEnabled(); ldapUrl = config.getLdapUrl(); ldapBindDn = config.getLdapBindDn(); ldapBindPassword = config.getLdapBindPassword(); ldapAuthenticationMechanism = config.getLdapAuthenticationMechanism(); ldapReferral = config.getContextReferral(); searchBase = config.getSearchBase(); userSearchBase = config.getUserSearchBase().split(";"); userSearchScope = config.getUserSearchScope(); userObjectClass = config.getUserObjectClass(); userSearchFilter = config.getUserSearchFilter(); extendedUserSearchFilter = "(objectclass=" + userObjectClass + ")"; if (userSearchFilter != null && !userSearchFilter.trim().isEmpty()) { String customFilter = userSearchFilter.trim(); if (!customFilter.startsWith("(")) { customFilter = "(" + customFilter + ")"; } extendedUserSearchFilter = "(&" + extendedUserSearchFilter + customFilter + ")"; } userNameAttribute = config.getUserNameAttribute(); Set<String> userSearchAttributes = new HashSet<String>(); userSearchAttributes.add(userNameAttribute); // For Group based search, user's group name attribute should not be added to the user search attributes if (!groupSearchFirstEnabled && !groupSearchEnabled) { userGroupNameAttributeSet = config.getUserGroupNameAttributeSet(); for (String useGroupNameAttribute : userGroupNameAttributeSet) { userSearchAttributes.add(useGroupNameAttribute); } } userSearchControls = new SearchControls(); userSearchControls.setSearchScope(userSearchScope); userSearchControls.setReturningAttributes(userSearchAttributes.toArray( new String[userSearchAttributes.size()])); pagedResultsEnabled = config.isPagedResultsEnabled(); pagedResultsSize = config.getPagedResultsSize(); groupSearchBase = config.getGroupSearchBase().split(";"); groupSearchScope = config.getGroupSearchScope(); groupObjectClass = config.getGroupObjectClass(); groupSearchFilter = config.getGroupSearchFilter(); groupMemberAttributeName = config.getUserGroupMemberAttributeName(); groupNameAttribute = config.getGroupNameAttribute(); extendedGroupSearchFilter = "(objectclass=" + groupObjectClass + ")"; if (groupSearchFilter != null && !groupSearchFilter.trim().isEmpty()) { String customFilter = groupSearchFilter.trim(); if (!customFilter.startsWith("(")) { customFilter = "(" + customFilter + ")"; } extendedGroupSearchFilter = extendedGroupSearchFilter + customFilter; } extendedAllGroupsSearchFilter = "(&" + extendedGroupSearchFilter + ")"; if (!groupSearchFirstEnabled) { extendedGroupSearchFilter = "(&" + extendedGroupSearchFilter + "(|(" + groupMemberAttributeName + "={0})(" + groupMemberAttributeName + "={1})))"; } groupUserMapSyncEnabled = config.isGroupUserMapSyncEnabled(); groupSearchControls = new SearchControls(); groupSearchControls.setSearchScope(groupSearchScope); Set<String> groupSearchAttributes = new HashSet<String>(); groupSearchAttributes.add(groupNameAttribute); groupSearchAttributes.add(groupMemberAttributeName); groupSearchControls.setReturningAttributes(groupSearchAttributes.toArray( new String[groupSearchAttributes.size()])); if (LOG.isInfoEnabled()) { LOG.info("LdapUserGroupBuilder initialization completed with -- " + "ldapUrl: " + ldapUrl + ", ldapBindDn: " + ldapBindDn + ", ldapBindPassword: ***** " + ", ldapAuthenticationMechanism: " + ldapAuthenticationMechanism + ", searchBase: " + searchBase + ", userSearchBase: " + Arrays.toString(userSearchBase) + ", userSearchScope: " + userSearchScope + ", userObjectClass: " + userObjectClass + ", userSearchFilter: " + userSearchFilter + ", extendedUserSearchFilter: " + extendedUserSearchFilter + ", userNameAttribute: " + userNameAttribute + ", userSearchAttributes: " + userSearchAttributes + ", userGroupNameAttributeSet: " + userGroupNameAttributeSet + ", pagedResultsEnabled: " + pagedResultsEnabled + ", pagedResultsSize: " + pagedResultsSize + ", groupSearchEnabled: " + groupSearchEnabled + ", groupSearchBase: " + Arrays.toString(groupSearchBase) + ", groupSearchScope: " + groupSearchScope + ", groupObjectClass: " + groupObjectClass + ", groupSearchFilter: " + groupSearchFilter + ", extendedGroupSearchFilter: " + extendedGroupSearchFilter + ", extendedAllGroupsSearchFilter: " + extendedAllGroupsSearchFilter + ", groupMemberAttributeName: " + groupMemberAttributeName + ", groupNameAttribute: " + groupNameAttribute + ", groupSearchAttributes: " + groupSearchAttributes + ", groupUserMapSyncEnabled: " + groupUserMapSyncEnabled + ", groupSearchFirstEnabled: " + groupSearchFirstEnabled + ", userSearchEnabled: " + userSearchEnabled + ", ldapReferral: " + ldapReferral ); } } private void closeLdapContext() throws Throwable { if (tls != null) { tls.close(); } if (ldapContext != null) { ldapContext.close(); } } @Override public boolean isChanged() { // we do not want to get the full ldap dit and check whether anything has changed return true; } @Override public void updateSink(UserGroupSink sink) throws Throwable { LOG.info("LDAPUserGroupBuilder updateSink started"); userGroupMap = new HashMap<String, UserInfo>(); if (!groupSearchFirstEnabled) { LOG.info("Performing user search first"); getUsers(sink); LOG.debug("Total No. of users saved = " + userGroupMap.size()); //Iterator<UserInfo> userInfoIterator = userGroupMap. for (UserInfo userInfo : userGroupMap.values()) { String userName = userInfo.getUserName(); if (groupSearchEnabled) { // Perform group search LOG.info("groupSearch is enabled, would search for groups and compute memberships"); getGroups(sink, userInfo); } List<String> groupList = userInfo.getGroups(); if (userNameCaseConversionFlag) { if (userNameLowerCaseFlag) { userName = userName.toLowerCase(); } else { userName = userName.toUpperCase(); } } if (userNameRegExInst != null) { userName = userNameRegExInst.transform(userName); } try { sink.addOrUpdateUser(userName, groupList); } catch (Throwable t) { LOG.error("sink.addOrUpdateUser failed with exception: " + t.getMessage() + ", for user: " + userName + ", groups: " + groupList); } } } else { LOG.info("Performing Group search first"); getGroups(sink, null); if (userSearchEnabled) { LOG.info("User search is enabled and hence computing user membership."); getUsers(sink); } else { LOG.info("User search is disabled and hence using the group member attribute for username."); // Go through the userInfo map and update ranger admin. for (UserInfo userInfo : userGroupMap.values()) { String userName = getShortUserName(userInfo.getUserFullName()); List<String> groupList = userInfo.getGroups(); if (userNameCaseConversionFlag) { if (userNameLowerCaseFlag) { userName = userName.toLowerCase(); } else { userName = userName.toUpperCase(); } } if (userNameRegExInst != null) { userName = userNameRegExInst.transform(userName); } try { sink.addOrUpdateUser(userName, groupList); } catch (Throwable t) { LOG.error("sink.addOrUpdateUser failed with exception: " + t.getMessage() + ", for user: " + userName + ", groups: " + groupList); } } } } } private void getUsers(UserGroupSink sink) throws Throwable { UserInfo userInfo; NamingEnumeration<SearchResult> userSearchResultEnum = null; NamingEnumeration<SearchResult> groupSearchResultEnum = null; try { createLdapContext(); int total; // Activate paged results if (pagedResultsEnabled) { ldapContext.setRequestControls(new Control[]{ new PagedResultsControl(pagedResultsSize, Control.NONCRITICAL) }); } // When multiple OUs are configured, go through each OU as the user search base to search for users. for (int ou=0; ou<userSearchBase.length; ou++) { byte[] cookie = null; int counter = 0; try { do { userSearchResultEnum = ldapContext .search(userSearchBase[ou], extendedUserSearchFilter, userSearchControls); while (userSearchResultEnum.hasMore()) { // searchResults contains all the user entries final SearchResult userEntry = userSearchResultEnum.next(); if (userEntry == null) { if (LOG.isInfoEnabled()) { LOG.info("userEntry null, skipping sync for the entry"); } continue; } Attributes attributes = userEntry.getAttributes(); if (attributes == null) { if (LOG.isInfoEnabled()) { LOG.info("attributes missing for entry " + userEntry.getNameInNamespace() + ", skipping sync"); } continue; } Attribute userNameAttr = attributes.get(userNameAttribute); if (userNameAttr == null) { if (LOG.isInfoEnabled()) { LOG.info(userNameAttribute + " missing for entry " + userEntry.getNameInNamespace() + ", skipping sync"); } continue; } String userName = (String) userNameAttr.get(); if (userName == null || userName.trim().isEmpty()) { if (LOG.isInfoEnabled()) { LOG.info(userNameAttribute + " empty for entry " + userEntry.getNameInNamespace() + ", skipping sync"); } continue; } if (!groupSearchFirstEnabled) { userInfo = new UserInfo(userName, userEntry.getNameInNamespace()); Set<String> groups = new HashSet<String>(); // Get all the groups from the group name attribute of the user only when group search is not enabled. if (!groupSearchEnabled) { for (String useGroupNameAttribute : userGroupNameAttributeSet) { Attribute userGroupfAttribute = userEntry.getAttributes().get(useGroupNameAttribute); if (userGroupfAttribute != null) { NamingEnumeration<?> groupEnum = userGroupfAttribute.getAll(); while (groupEnum.hasMore()) { String gName = getShortGroupName((String) groupEnum .next()); if (groupNameCaseConversionFlag) { if (groupNameLowerCaseFlag) { gName = gName.toLowerCase(); } else { gName = gName.toUpperCase(); } } if (groupNameRegExInst != null) { gName = groupNameRegExInst.transform(gName); } groups.add(gName); } } } } userInfo.addGroups(groups); //populate the userGroupMap with username, userInfo. //userInfo contains details of user that will be later used for //group search to compute group membership as well as to call sink.addOrUpdateUser() if (userGroupMap.containsKey(userName)) { LOG.warn("user object with username " + userName + " already exists and is replaced with the latest user object." ); } userGroupMap.put(userName, userInfo); //List<String> groupList = new ArrayList<String>(groups); List<String> groupList = userInfo.getGroups(); counter++; if (counter <= 2000) { if (LOG.isInfoEnabled()) { LOG.info("Updating user count: " + counter + ", userName: " + userName + ", groupList: " + groupList); } if ( counter == 2000 ) { LOG.info("===> 2000 user records have been synchronized so far. From now on, only a summary progress log will be written for every 100 users. To continue to see detailed log for every user, please enable Trace level logging. <==="); } } else { if (LOG.isTraceEnabled()) { LOG.trace("Updating user count: " + counter + ", userName: " + userName + ", groupList: " + groupList); } else { if ( counter % 100 == 0) { LOG.info("Synced " + counter + " users till now"); } } } } else { // If the user from the search result is present in the usersList, // then update user name in the userInfo map with the value from the search result // and update ranger admin. String userFullName = (userEntry.getNameInNamespace()).toLowerCase(); LOG.debug("Chekcing if the user " + userFullName + " is part of the retrieved groups"); userInfo = userGroupMap.get(userFullName); if (userInfo == null) { userInfo = userGroupMap.get(userName.toLowerCase()); } if (userInfo != null) { counter++; LOG.info("Updating username for " + userFullName + " with " + userName); userInfo.updateUserName(userName); List<String> groupList = userInfo.getGroups(); if (userNameCaseConversionFlag) { if (userNameLowerCaseFlag) { userName = userName.toLowerCase(); } else { userName = userName.toUpperCase(); } } if (userNameRegExInst != null) { userName = userNameRegExInst.transform(userName); } try { sink.addOrUpdateUser(userName, groupList); } catch (Throwable t) { LOG.error("sink.addOrUpdateUser failed with exception: " + t.getMessage() + ", for user: " + userName + ", groups: " + groupList); } } } } // Examine the paged results control response Control[] controls = ldapContext.getResponseControls(); if (controls != null) { for (int i = 0; i < controls.length; i++) { if (controls[i] instanceof PagedResultsResponseControl) { PagedResultsResponseControl prrc = (PagedResultsResponseControl)controls[i]; total = prrc.getResultSize(); if (total != 0) { LOG.debug("END-OF-PAGE total : " + total); } else { LOG.debug("END-OF-PAGE total : unknown"); } cookie = prrc.getCookie(); } } } else { LOG.debug("No controls were sent from the server"); } // Re-activate paged results if (pagedResultsEnabled) { ldapContext.setRequestControls(new Control[]{ new PagedResultsControl(PAGE_SIZE, cookie, Control.CRITICAL) }); } } while (cookie != null); LOG.info("LDAPUserGroupBuilder.getUsers() completed with user count: " + counter); } catch (Throwable t) { LOG.error("LDAPUserGroupBuilder.getUsers() failed with exception: " + t); LOG.info("LDAPUserGroupBuilder.getUsers() user count: " + counter); } } } finally { if (userSearchResultEnum != null) { userSearchResultEnum.close(); } if (groupSearchResultEnum != null) { groupSearchResultEnum.close(); } closeLdapContext(); } } private void getGroups(UserGroupSink sink, UserInfo userInfo) throws Throwable { NamingEnumeration<SearchResult> groupSearchResultEnum = null; try { createLdapContext(); int total; // Activate paged results if (pagedResultsEnabled) { ldapContext.setRequestControls(new Control[]{ new PagedResultsControl(pagedResultsSize, Control.NONCRITICAL) }); } for (int ou=0; ou<groupSearchBase.length; ou++) { byte[] cookie = null; int counter = 0; try { do { if (!groupSearchFirstEnabled) { if (userInfo == null) { // Should never reach this. LOG.error("No user information provided for group search!"); return; } groupSearchResultEnum = ldapContext .search(groupSearchBase[ou], extendedGroupSearchFilter, new Object[]{userInfo.getUserFullName(), userInfo.getUserName()}, groupSearchControls); } else { // If group based search is enabled, then first retrieve all the groups based on the group configuration. groupSearchResultEnum = ldapContext .search(groupSearchBase[ou], extendedAllGroupsSearchFilter, groupSearchControls); } while (groupSearchResultEnum.hasMore()) { final SearchResult groupEntry = groupSearchResultEnum.next(); if (groupEntry != null) { counter++; Attribute groupNameAttr = groupEntry.getAttributes().get(groupNameAttribute); if (groupNameAttr == null) { if (LOG.isInfoEnabled()) { LOG.info(groupNameAttribute + " empty for entry " + groupEntry.getNameInNamespace() + ", skipping sync"); } continue; } String gName = (String) groupNameAttr.get(); if (groupNameCaseConversionFlag) { if (groupNameLowerCaseFlag) { gName = gName.toLowerCase(); } else { gName = gName.toUpperCase(); } } if (groupNameRegExInst != null) { gName = groupNameRegExInst.transform(gName); } if (!groupSearchFirstEnabled) { //computedGroups.add(gName); if (LOG.isInfoEnabled()) { LOG.info("computed groups for user: " + userInfo.getUserName() +", groups: " + gName); } userInfo.addGroup(gName); } else { // If group based search is enabled, then // update the group name to ranger admin // check for group members and populate userInfo object with user's full name and group mapping Attribute groupMemberAttr = groupEntry.getAttributes().get(groupMemberAttributeName); LOG.debug("Update Ranger admin with " + gName); sink.addOrUpdateGroup(gName); int userCount = 0; if (groupMemberAttr == null || groupMemberAttr.size() <= 0) { LOG.info("No members available for " + gName); continue; } NamingEnumeration<?> userEnum = groupMemberAttr.getAll(); while (userEnum.hasMore()) { String originalUserFullName = (String) userEnum.next(); if (originalUserFullName == null || originalUserFullName.trim().isEmpty()) { continue; } String userFullName = originalUserFullName.toLowerCase(); userCount++; if (!userGroupMap.containsKey(userFullName)) { userInfo = new UserInfo(userFullName, originalUserFullName); // Preserving the original full name for later userGroupMap.put(userFullName, userInfo); } else { userInfo = userGroupMap.get(userFullName); } LOG.info("Adding " + gName + " to user " + userInfo.getUserFullName()); userInfo.addGroup(gName); } LOG.info("No. of members in the group " + gName + " = " + userCount); } } } // Examine the paged results control response Control[] controls = ldapContext.getResponseControls(); if (controls != null) { for (int i = 0; i < controls.length; i++) { if (controls[i] instanceof PagedResultsResponseControl) { PagedResultsResponseControl prrc = (PagedResultsResponseControl)controls[i]; total = prrc.getResultSize(); if (total != 0) { LOG.debug("END-OF-PAGE total : " + total); } else { LOG.debug("END-OF-PAGE total : unknown"); } cookie = prrc.getCookie(); } } } else { LOG.debug("No controls were sent from the server"); } // Re-activate paged results if (pagedResultsEnabled) { ldapContext.setRequestControls(new Control[]{ new PagedResultsControl(PAGE_SIZE, cookie, Control.CRITICAL) }); } } while (cookie != null); LOG.info("LDAPUserGroupBuilder.getGroups() completed with group count: " + counter); } catch (Throwable t) { LOG.error("LDAPUserGroupBuilder.getGroups() failed with exception: " + t); LOG.info("LDAPUserGroupBuilder.getGroups() group count: " + counter); } } } finally { if (groupSearchResultEnum != null) { groupSearchResultEnum.close(); } closeLdapContext(); } } private static String getShortGroupName(String longGroupName) throws InvalidNameException { if (longGroupName == null) { return null; } StringTokenizer stc = new StringTokenizer(longGroupName, ","); String firstToken = stc.nextToken(); StringTokenizer ste = new StringTokenizer(firstToken, "="); String groupName = ste.nextToken(); if (ste.hasMoreTokens()) { groupName = ste.nextToken(); } groupName = groupName.trim(); LOG.info("longGroupName: " + longGroupName + ", groupName: " + groupName); return groupName; } private static String getShortUserName(String longUserName) throws InvalidNameException { if (longUserName == null) { return null; } StringTokenizer stc = new StringTokenizer(longUserName, ","); String firstToken = stc.nextToken(); StringTokenizer ste = new StringTokenizer(firstToken, "="); String userName = ste.nextToken(); if (ste.hasMoreTokens()) { userName = ste.nextToken(); } userName = userName.trim(); LOG.info("longUserName: " + longUserName + ", userName: " + userName); return userName; } } class UserInfo { private String userName; private String userFullName; private Set<String> groupList; public UserInfo(String userName, String userFullName) { this.userName = userName; this.userFullName = userFullName; this.groupList = new HashSet<String>(); } public void updateUserName(String userName) { this.userName = userName; } public String getUserName() { return userName; } public String getUserFullName() { return userFullName; } public void addGroups(Set<String> groups) { groupList.addAll(groups); } public void addGroup(String group) { groupList.add(group); } public List<String> getGroups() { return (new ArrayList<String>(groupList)); } }