Java tutorial
/* * SSL-Explorer * * Copyright (C) 2003-2006 3SP LTD. All Rights Reserved * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ package com.sslexplorer.jdbc; import java.io.File; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.Arrays; import java.util.Calendar; import java.util.Collection; import java.util.Collections; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Vector; import java.util.regex.Pattern; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import com.sslexplorer.boot.ContextHolder; import com.sslexplorer.boot.SystemProperties; import com.sslexplorer.boot.Util; import com.sslexplorer.core.CoreEvent; import com.sslexplorer.core.CoreEventConstants; import com.sslexplorer.core.CoreListener; import com.sslexplorer.core.CoreServlet; import com.sslexplorer.navigation.DefaultFavorite; import com.sslexplorer.navigation.Favorite; import com.sslexplorer.security.AuthenticationModuleManager; import com.sslexplorer.security.AuthenticationScheme; import com.sslexplorer.security.DefaultAuthenticationScheme; import com.sslexplorer.security.IpRestriction; import com.sslexplorer.security.SystemDatabase; import com.sslexplorer.security.User; import com.sslexplorer.util.CIDRNetwork; /** * Implementation of a {@link com.sslexplorer.security.SystemDatabase} that uses * a JDBC compliant database to store SSL-Explorer's basic configuration and * resources. */ public class JDBCSystemDatabase implements SystemDatabase, CoreListener { private static final Log log = LogFactory.getLog(JDBCSystemDatabase.class); private static final String LOCAL_HOST = "localhost"; private static final String LOCAL_LOOP_BACK_IPV4 = "127.0.0.1"; private static final String LOCAL_LOOP_BACK_IPV6 = "::1"; private static final String LOCAL_LOOP_BACK_IPV6_EXT = "0:0:0:0:0:0:0:1"; private final Collection<String> authorizedIPAddresses = new HashSet<String>(); private final Collection<String> excludedIPAddresses = new HashSet<String>(); private JDBCDatabaseEngine db; /** * Constructor */ public JDBCSystemDatabase() { initialiseIpRestrictionCache(); } /* (non-Javadoc) * @see com.sslexplorer.core.Database#open(com.sslexplorer.core.CoreServlet) */ public void open(CoreServlet controllingServlet) throws Exception { String dbName = SystemProperties.get("sslexplorer.systemDatabase.jdbc.dbName", "explorer_configuration"); controllingServlet.addDatabase(dbName, ContextHolder.getContext().getDBDirectory()); String jdbcUser = SystemProperties.get("sslexplorer.jdbc.username", "sa"); String jdbcPassword = SystemProperties.get("sslexplorer.jdbc.password", ""); String vendorDB = SystemProperties.get("sslexplorer.jdbc.vendorClass", "com.sslexplorer.jdbc.hsqldb.HSQLDBDatabaseEngine"); if (log.isInfoEnabled()) { log.info("System database is being opened..."); log.info("JDBC vendor class implementation is " + vendorDB); } db = (JDBCDatabaseEngine) Class.forName(vendorDB).newInstance(); db.init("systemDatabase", dbName, jdbcUser, jdbcPassword, null); File upgradeDir = new File("install/upgrade"); DBUpgrader upgrader = new DBUpgrader(ContextHolder.getContext().getVersion(), db, ContextHolder.getContext().getDBDirectory(), upgradeDir); upgrader.upgrade(); CoreServlet.getServlet().addCoreListener(this); } /* * (non-Javadoc) * @see com.sslexplorer.boot.Database#close() */ public void close() throws Exception { } /* * (non-Javadoc) * @see com.sslexplorer.boot.Database#cleanup() */ public void cleanup() throws Exception { } /* * (non-Javadoc) * @see com.sslexplorer.core.CoreListener#coreEvent(com.sslexplorer.core.CoreEvent) */ public void coreEvent(CoreEvent evt) { if (evt.getId() == CoreEventConstants.USER_REMOVED) { User user = (User) evt.getParameter(); // LDP - Fix as null user might be passed? if (user == null) return; try { removeUser(user.getPrincipalName()); } catch (Exception e) { log.error("Failed to remove user from system database.", e); } } } private void initialiseIpRestrictionCache() { synchronized (authorizedIPAddresses) { authorizedIPAddresses.clear(); authorizedIPAddresses.addAll(getAlwaysAuthorizedIpAddresses()); excludedIPAddresses.clear(); } } private static Collection<String> getAlwaysAuthorizedIpAddresses() { String property = SystemProperties.get("sslexplorer.iprestrictions.allow", ""); Collection<String> propertyAsCollection = property.length() == 0 ? Collections.<String>emptyList() : Arrays.asList(property.split(",")); /* BPS - It is possible to spoof localhost, although most firewalls should prevent this happening, * do we really want to just allow localhost? */ Collection<String> alwaysAuthorized = new HashSet<String>(); alwaysAuthorized.add(LOCAL_HOST); alwaysAuthorized.add(LOCAL_LOOP_BACK_IPV4); alwaysAuthorized.add(LOCAL_LOOP_BACK_IPV6); alwaysAuthorized.add(LOCAL_LOOP_BACK_IPV6_EXT); alwaysAuthorized.addAll(propertyAsCollection); return alwaysAuthorized; } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#verifyIPAddress(java.lang.String) */ public boolean verifyIPAddress(String ipAddress) throws Exception { // Check if the state of this ip address is cached if (authorizedIPAddresses.contains(ipAddress)) { return true; } else if (excludedIPAddresses.contains(ipAddress)) { return false; } IpRestriction[] ipRestrictions = getIpRestrictions(); return verifyIPAddress(ipAddress, ipRestrictions); } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#verifyIPAddress(java.lang.String, com.sslexplorer.security.IpRestriction[]) */ public boolean verifyIPAddress(String ipAddress, IpRestriction[] ipRestrictions) throws Exception { synchronized (authorizedIPAddresses) { boolean isValid = isAddressValid(ipAddress, ipRestrictions); if (isValid) { // Cache IP addresses to stop us doing too many lookups authorizedIPAddresses.add(ipAddress); } else { excludedIPAddresses.add(ipAddress); } return isValid; } } /** * @param ipAddress * @param ipRestrictions * @return boolean * @throws Exception */ private boolean isAddressValid(String ipAddress, IpRestriction[] ipRestrictions) throws Exception { /* BPS - It is possible to spoof localhost, although most firewalls should prevent this happening, * do we really want to just allow localhost? */ if (LOCAL_LOOP_BACK_IPV4.equals(ipAddress) || LOCAL_LOOP_BACK_IPV6.equals(ipAddress) || LOCAL_LOOP_BACK_IPV6_EXT.equals(ipAddress) || LOCAL_HOST.equalsIgnoreCase(ipAddress)) { return true; } if (ipAddress.length() == 0) { return true; } // No restrictions at all. Allow. Should only happen on bad upgrades if (ipRestrictions.length == 0) { return true; } /* Get the last matching state. We use the IpRestriction type constants as a convenience while iterating over the restrictions, nothing more */ int state = -1; for (int i = 0; i < ipRestrictions.length; i++) { if (matchesAddress(ipRestrictions[i], ipAddress)) { state = ipRestrictions[i].getAllowed() ? IpRestriction.ALLOWED : IpRestriction.DENIED; } } return state == IpRestriction.ALLOWED; } /** * @param restriction * @param ipAddress * @return boolean */ private boolean matchesAddress(IpRestriction restriction, String ipAddress) { String ipRestrictionAddress = restriction.getAddress(); if (isIpAddressMatch(ipAddress, ipRestrictionAddress)) { return true; } else if (restriction.isWildcardMatch() && isIpAddressWildcardMatch(ipAddress, ipRestrictionAddress)) { return true; } else if (isCIDRMatch(ipAddress, ipRestrictionAddress)) { return true; } return false; } /** * @param toCheck * @param ipRestrictionAddress * @return boolean */ private static boolean isIpAddressMatch(String toCheck, String ipRestrictionAddress) { return toCheck.equals(ipRestrictionAddress); } /** * @param toCheck * @param ipRestrictionAddress * @return boolean */ private static boolean isIpAddressWildcardMatch(String toCheck, String ipRestrictionAddress) { String regex = Util.parseSimplePatternToRegExp(ipRestrictionAddress); return Pattern.matches(regex, toCheck); } /** * @param toCheck * @param ipRestrictionAddress * @return boolean */ private static boolean isCIDRMatch(String toCheck, String ipRestrictionAddress) { try { CIDRNetwork network = new CIDRNetwork(ipRestrictionAddress); return network.isValidAddressForNetwork(toCheck); } catch (Exception e) { return false; } } public void addIpRestriction(String addressPattern, int type) throws Exception { IpRestriction[] r = getIpRestrictions(); int priority = (r == null || r.length == 0 ? 10 : r[r.length - 1].getPriority()) + 10; JDBCPreparedStatement ps = db.getStatement("addIpRestriction.insert"); try { ps.setString(1, addressPattern); ps.setInt(2, type); ps.setInt(3, priority); ps.execute(); } finally { ps.releasePreparedStatement(); initialiseIpRestrictionCache(); } } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#updateIpRestriction(com.sslexplorer.security.IpRestriction) */ public void updateIpRestriction(IpRestriction restriction) throws Exception { JDBCPreparedStatement ps = db.getStatement("updateIpRestriction.update"); try { ps.setString(1, restriction.getAddress()); ps.setInt(2, restriction.getType()); ps.setInt(3, restriction.getPriority()); ps.setInt(4, restriction.getID()); ps.execute(); } finally { ps.releasePreparedStatement(); initialiseIpRestrictionCache(); } } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#swapIpRestrictions(com.sslexplorer.security.IpRestriction, com.sslexplorer.security.IpRestriction) */ public void swapIpRestrictions(IpRestriction restriction1, IpRestriction restriction2) throws Exception { if (restriction1.isDefault() || restriction2.isDefault()) { throw new IllegalArgumentException("You may not move the default Ip restriction."); } int priority2 = restriction2.getPriority(); restriction2.setPriority(restriction1.getPriority()); restriction1.setPriority(priority2); updateIpRestriction(restriction1); updateIpRestriction(restriction2); } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getIpRestrictions() */ public IpRestriction[] getIpRestrictions() throws Exception { JDBCPreparedStatement statement = db.getStatement("getIpRestrictions.select"); Collection<IpRestriction> restrictions = new ArrayList<IpRestriction>(); ResultSet resultSet = null; try { resultSet = statement.executeQuery(); while (resultSet.next()) { restrictions.add(buildIpRestriction(resultSet)); } } finally { JDBCUtil.cleanup(resultSet); statement.releasePreparedStatement(); } return restrictions.toArray(new IpRestriction[restrictions.size()]); } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getIpRestriction(int) */ public IpRestriction getIpRestriction(int id) throws Exception { JDBCPreparedStatement ps = db.getStatement("getIpRestriction.select"); ps.setInt(1, id); try { ResultSet rs = ps.executeQuery(); try { if (rs.next()) { return buildIpRestriction(rs); } } finally { rs.close(); } } finally { ps.releasePreparedStatement(); } return null; } /** * @param resultSet * @return IpRestriction * @throws SQLException */ private static IpRestriction buildIpRestriction(ResultSet resultSet) throws SQLException { return new IpRestriction(resultSet.getInt("restriction_id"), resultSet.getString("address"), resultSet.getInt("type"), resultSet.getInt("priority")); } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#removeIpRestriction(int) */ public void removeIpRestriction(int id) throws Exception { JDBCPreparedStatement ps = db.getStatement("removeIpRestriction.delete"); try { ps.setInt(1, id); ps.execute(); } finally { ps.releasePreparedStatement(); initialiseIpRestrictionCache(); } } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#addFavorite(int, int, java.lang.String) */ public void addFavorite(int type, int favoriteKey, String username) throws Exception { JDBCPreparedStatement ps = db.getStatement("addFavorite.insert"); try { ps.setInt(1, type); ps.setString(2, username == null ? "" : username); ps.setInt(3, favoriteKey); ps.execute(); ps.reset(); } finally { ps.releasePreparedStatement(); } } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#removeFavorite(int, int, java.lang.String) */ public void removeFavorite(int type, int favoriteKey, String username) throws Exception { JDBCPreparedStatement ps = db.getStatement("removeFavorite.delete"); try { ps.setInt(1, type); ps.setString(2, username == null ? "" : username); ps.setInt(3, favoriteKey); ps.execute(); } finally { ps.releasePreparedStatement(); } } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getFavorites(int, com.sslexplorer.security.User) */ public List<Favorite> getFavorites(int type, User user) throws Exception { JDBCPreparedStatement ps = null; if (type == -1) { ps = db.getStatement("getFavorites.selectAllForUser"); ps.setString(1, user == null ? "" : user.getPrincipalName()); } else { ps = db.getStatement("getFavorites.selectTypeForUser"); ps.setString(1, user == null ? "" : user.getPrincipalName()); ps.setInt(2, type); } try { Vector<Favorite> v = new Vector<Favorite>(); ResultSet rs = ps.executeQuery(); try { while (rs.next()) { v.add(new DefaultFavorite(rs.getInt("favorite_id"), type, user == null ? null : user.getPrincipalName(), rs.getInt("favorite_key"))); } } finally { rs.close(); } return v; } finally { ps.releasePreparedStatement(); } } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getFavorite(int, com.sslexplorer.security.User, java.lang.String) */ public Favorite getFavorite(int type, User user, int resourceId) throws Exception { JDBCPreparedStatement ps = db.getStatement("getFavorite.select"); ps.setString(1, user == null ? "" : user.getPrincipalName()); ps.setInt(2, type); ps.setInt(3, resourceId); try { ResultSet rs = ps.executeQuery(); try { if (rs.next()) { return new DefaultFavorite(rs.getInt("favorite_id"), type, user == null ? null : user.getPrincipalName(), rs.getInt("favorite_key")); } } finally { rs.close(); } } finally { ps.releasePreparedStatement(); } return null; } // Authentication Schemes /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getAuthenticationSchemeSequences() */ public List<AuthenticationScheme> getAuthenticationSchemeSequences() throws Exception { JDBCPreparedStatement ps = db.getStatement("getAuthenticationSchemeSequences.select"); try { ResultSet rs = ps.executeQuery(); try { List<AuthenticationScheme> sequences = new ArrayList<AuthenticationScheme>(); while (rs.next()) { AuthenticationScheme sequence = buildAuthenticationSchemeSequence(rs); if (sequence != null) { sequences.add(sequence); } } return sequences; } finally { rs.close(); } } finally { ps.releasePreparedStatement(); } } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getAuthenticationSchemeSequence(int) */ public AuthenticationScheme getAuthenticationSchemeSequence(int id) throws Exception { JDBCPreparedStatement ps = db.getStatement("getAuthenticationSchemeSequence.select"); ResultSet rs = null; try { ps.setInt(1, id); rs = ps.executeQuery(); if (rs.next()) { return buildAuthenticationSchemeSequence(rs); } } finally { JDBCUtil.cleanup(rs); ps.releasePreparedStatement(); } return null; } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#getAuthenticationSchemeSequence(java.lang.String, int) */ public AuthenticationScheme getAuthenticationSchemeSequence(String name, int realmID) throws Exception { JDBCPreparedStatement ps = db.getStatement("getAuthenticationSchemeSequence.select.byName"); ResultSet rs = null; try { ps.setInt(1, realmID); ps.setString(2, name); rs = ps.executeQuery(); if (rs.next()) { return buildAuthenticationSchemeSequence(rs); } } finally { JDBCUtil.cleanup(rs); ps.releasePreparedStatement(); } return null; } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#createAuthenticationSchemeSequence(int, java.lang.String, java.lang.String, java.lang.String[], boolean, int) */ public AuthenticationScheme createAuthenticationSchemeSequence(int realmID, String name, String description, String[] modules, boolean enabled, int priority) throws Exception { Calendar calendar = Calendar.getInstance(); String timestamp = db.formatTimestamp(calendar); JDBCPreparedStatement ps = db.getStatement("createAuthenticationSchemeSequence.insert"); try { ps.setString(1, name); ps.setString(2, description); ps.setString(3, timestamp); ps.setString(4, timestamp); ps.setInt(5, enabled ? 1 : 0); ps.setInt(6, priority); ps.setInt(7, realmID); ps.execute(); int id = db.getLastInsertId(ps, "createAuthenticationSchemeSequence.lastInsertId"); AuthenticationScheme sequence = getAuthenticationSchemeSequence(id); updateAuthenticationSequence(sequence, modules); return sequence; } finally { ps.releasePreparedStatement(); } } private void updateAuthenticationSequence(AuthenticationScheme sequence, String[] modules) throws Exception { for (int index = 0; index < modules.length; index++) { sequence.addModule(modules[index]); } updateSequence(sequence); } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#updateAuthenticationSchemeSequence(com.sslexplorer.security.AuthenticationScheme) */ public void updateAuthenticationSchemeSequence(AuthenticationScheme sequence) throws Exception { JDBCPreparedStatement ps = db.getStatement("updateAuthenticationSchemeSequence.update"); try { ps.setString(1, sequence.getResourceName()); ps.setString(2, sequence.getResourceDescription()); Calendar now = Calendar.getInstance(); ps.setString(3, db.formatTimestamp(now)); ps.setInt(4, sequence.getEnabled() ? 1 : 0); ps.setInt(5, sequence.getResourceId()); ps.execute(); updateSequence(sequence); } finally { ps.releasePreparedStatement(); } } /** * @param sequence * @throws Exception */ private void updateSequence(AuthenticationScheme sequence) throws Exception { deleteAuthenticationSequence(sequence.getResourceId()); updateAuthentictionSequence(sequence); } private void updateAuthentictionSequence(AuthenticationScheme sequence) throws Exception { JDBCPreparedStatement statement = db.getStatement("updateSequence.insert"); try { int seq = 0; for (Iterator itr = sequence.modules(); itr.hasNext();) { String module = (String) itr.next(); statement.setInt(1, sequence.getResourceId()); statement.setString(2, module); statement.setInt(3, seq); statement.execute(); seq += 10; statement.reset(); } } finally { statement.releasePreparedStatement(); } } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#moveAuthenticationSchemeUp(com.sslexplorer.security.AuthenticationScheme, java.util.List) */ public void moveAuthenticationSchemeUp(AuthenticationScheme scheme, List<AuthenticationScheme> schemes) throws Exception { int indexOf = schemes.indexOf(scheme); if (indexOf == 0) throw new IllegalStateException("Scheme is already set to highest priority"); int schemeAboveIndex = indexOf - 1; AuthenticationScheme schemeAbove = schemes.get(schemeAboveIndex); updateAuthenticationSchemePriority(scheme, schemeAbove.getPriorityInt()); updateAuthenticationSchemePriority(schemeAbove, scheme.getPriorityInt()); } /* (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#moveAuthenticationSchemeDown(com.sslexplorer.security.AuthenticationScheme, java.util.List) */ public void moveAuthenticationSchemeDown(AuthenticationScheme scheme, List<AuthenticationScheme> schemes) throws Exception { int indexOf = schemes.indexOf(scheme); if (indexOf == schemes.size() - 1) throw new IllegalStateException("Scheme is already set to lowest priority"); int schemeBelowIndex = indexOf + 1; AuthenticationScheme schemeBelow = schemes.get(schemeBelowIndex); updateAuthenticationSchemePriority(scheme, schemeBelow.getPriorityInt()); updateAuthenticationSchemePriority(schemeBelow, scheme.getPriorityInt()); } private void updateAuthenticationSchemePriority(AuthenticationScheme scheme, int priority) throws Exception { JDBCPreparedStatement ps = db.getStatement("updateAuthenticationSchemeSequence.update.priority"); try { ps.setInt(1, priority); ps.setInt(2, scheme.getResourceId()); ps.execute(); } finally { ps.releasePreparedStatement(); } } /* * (non-Javadoc) * @see com.sslexplorer.security.SystemDatabase#deleteAuthenticationSchemeSequence(java.lang.String) */ public void deleteAuthenticationSchemeSequence(int id) throws Exception { AuthenticationScheme scheme = getAuthenticationSchemeSequence(id); if (scheme == null) { throw new Exception("No authentication scheme with " + id + "."); } deleteAuthenticationScheme(id); deleteAuthenticationSequence(id); } private void deleteAuthenticationScheme(int id) throws SQLException, ClassNotFoundException { JDBCPreparedStatement ps = db.getStatement("deleteAuthenticationSchemeSequence.delete.authSchemes"); try { ps.setInt(1, id); ps.execute(); } finally { ps.releasePreparedStatement(); } } private void deleteAuthenticationSequence(int id) throws SQLException, ClassNotFoundException { JDBCPreparedStatement ps; ps = db.getStatement("deleteAuthenticationSchemeSequence.delete.authSequence"); try { ps.setInt(1, id); ps.execute(); } finally { ps.releasePreparedStatement(); } } /** * @param resultSet * @return AuthenticationScheme * @throws Exception */ private AuthenticationScheme buildAuthenticationSchemeSequence(ResultSet resultSet) throws Exception { Calendar created = JDBCUtil.getCalendar(resultSet, "date_created"); Calendar amended = JDBCUtil.getCalendar(resultSet, "date_amended"); boolean enabled = resultSet.getInt("enabled") == 1; AuthenticationScheme seq = new DefaultAuthenticationScheme(resultSet.getInt("realm_id"), resultSet.getInt("resource_id"), resultSet.getString("resource_name"), resultSet.getString("resource_description"), created, amended, enabled, resultSet.getInt("priority")); return isSchemeAvailable(seq) ? seq : null; } private boolean isSchemeAvailable(AuthenticationScheme scheme) throws Exception { JDBCPreparedStatement statement = db.getStatement("buildAuthenticationSchemeSequences.select.scheme"); ResultSet resultSet = null; boolean available = true; try { statement.setInt(1, scheme.getResourceId()); resultSet = statement.executeQuery(); while (resultSet.next()) { String moduleId = resultSet.getString("module_id"); if (!AuthenticationModuleManager.getInstance().isRegistered(moduleId)) { available = false; } scheme.addModule(moduleId); } } finally { JDBCUtil.cleanup(resultSet); statement.releasePreparedStatement(); } return available; } /** * @param username * @throws Exception */ protected void removeUser(String username) throws Exception { String[] statements = { "removeUser.delete.explorerProperties", "removeUser.delete.propertyProfiles" }; for (int i = 0; i < statements.length; i++) { JDBCPreparedStatement ps = db.getStatement(statements[i]); try { ps.setString(1, username); ps.execute(); } finally { ps.releasePreparedStatement(); } } } public List<AuthenticationScheme> getAuthenticationSchemeSequences(int realmID) throws Exception { JDBCPreparedStatement ps = db.getStatement("getAuthenticationSchemeSequences.realm.select"); try { ps.setInt(1, realmID); ResultSet rs = ps.executeQuery(); try { List<AuthenticationScheme> sequences = new ArrayList<AuthenticationScheme>(); while (rs.next()) { AuthenticationScheme sequence = buildAuthenticationSchemeSequence(rs); if (sequence != null) { sequences.add(sequence); } } return sequences; } finally { rs.close(); } } finally { ps.releasePreparedStatement(); } } }