2 * ============LICENSE_START=======================================================
4 * ================================================================================
5 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
6 * ================================================================================
7 * Copyright (C) 2017 Amdocs
8 * =============================================================================
9 * Licensed under the Apache License, Version 2.0 (the "License");
10 * you may not use this file except in compliance with the License.
11 * You may obtain a copy of the License at
13 * http://www.apache.org/licenses/LICENSE-2.0
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
21 * ECOMP is a trademark and service mark of AT&T Intellectual Property.
22 * ============LICENSE_END=========================================================
25 package org.openecomp.appc.lockmanager.impl.sql.optimistic;
27 import java.sql.Connection;
28 import java.sql.PreparedStatement;
29 import java.sql.ResultSet;
30 import java.sql.SQLException;
32 import org.openecomp.appc.lockmanager.api.LockException;
33 import org.openecomp.appc.lockmanager.api.LockRuntimeException;
34 import org.openecomp.appc.lockmanager.impl.sql.JdbcLockManager;
35 import org.openecomp.appc.lockmanager.impl.sql.Messages;
37 abstract class SqlLockManager extends JdbcLockManager {
39 private static final String SQL_LOAD_LOCK_RECORD = "SELECT * FROM %s WHERE RESOURCE_ID=?";
40 private static final String SQL_INSERT_LOCK_RECORD = "INSERT INTO %s (RESOURCE_ID, OWNER_ID, UPDATED, TIMEOUT, VER) VALUES (?, ?, ?, ?, ?)";
41 private static final String SQL_UPDATE_LOCK_RECORD = "UPDATE %s SET OWNER_ID=?, UPDATED=?, TIMEOUT=?, VER=? WHERE RESOURCE_ID=? AND VER=?";
42 // private static final String SQL_DELETE_LOCK_RECORD = "DELETE FROM %s WHERE RESOURCE_ID=? AND VER=?";
43 private static final String SQL_CURRENT_TIMESTAMP = "SELECT CURRENT_TIMESTAMP()";
45 private String sqlLoadLockRecord;
46 private String sqlInsertLockRecord;
47 private String sqlUpdateLockRecord;
48 // private String sqlDeleteLockRecord;
51 public boolean acquireLock(String resource, String owner) throws LockException {
52 return acquireLock(resource, owner, 0);
56 public boolean acquireLock(String resource, String owner, long timeout) throws LockException {
58 throw new LockRuntimeException(Messages.ERR_NULL_LOCK_OWNER.format(resource));
61 Connection connection = openDbConnection();
63 res = lockResource(connection, resource, owner, timeout);
65 closeDbConnection(connection);
71 public void releaseLock(String resource, String owner) throws LockException {
72 Connection connection = openDbConnection();
74 unlockResource(connection, resource, owner);
76 closeDbConnection(connection);
81 public boolean isLocked(String resource) {
82 Connection connection=openDbConnection();
84 LockRecord lockRecord=loadLockRecord(connection,resource);
88 if(lockRecord.getOwner()==null){
90 }else if(isLockExpired(lockRecord, connection)){
96 } catch (SQLException e) {
97 throw new LockRuntimeException(Messages.EXP_CHECK_LOCK.format(resource));
99 closeDbConnection(connection);
103 private boolean lockResource(Connection connection, String resource, String owner, long timeout) throws LockException {
106 LockRecord lockRecord = loadLockRecord(connection, resource);
107 if(lockRecord != null) {
108 // lock record already exists
109 String currentOwner = lockRecord.getOwner();
110 if(currentOwner != null) {
111 if(isLockExpired(lockRecord, connection)) {
113 } else if(!owner.equals(currentOwner)) {
114 throw new LockException(Messages.ERR_LOCK_LOCKED_BY_OTHER.format(resource, owner, currentOwner));
117 // set new owner on the resource lock record
118 if(!updateLockRecord(connection, resource, owner, timeout, lockRecord.getVer())) {
119 // try again - maybe same owner updated the record
120 lockResource(connection, resource, owner, timeout);
122 if(currentOwner == null) {
123 // no one locked the resource before
127 // resource record does not exist in lock table => create new record
129 addLockRecord(connection, resource, owner, timeout);
131 } catch(SQLException e) {
132 if(isDuplicatePkError(e)) {
133 // try again - maybe same owner inserted the record
134 lockResource(connection, resource, owner, timeout);
141 } catch(SQLException e) {
142 throw new LockRuntimeException(Messages.EXP_LOCK.format(resource), e);
146 protected boolean isDuplicatePkError(SQLException e) {
147 return e.getSQLState().startsWith("23");
150 private void unlockResource(Connection connection, String resource, String owner) throws LockException {
152 LockRecord lockRecord = loadLockRecord(connection, resource);
153 if(lockRecord != null) {
155 if(isLockExpired(lockRecord, connection)) {
156 // lock is expired => no lock
160 if((lockRecord == null) || (lockRecord.getOwner() == null)) {
161 // resource is not locked
162 throw new LockException(Messages.ERR_UNLOCK_NOT_LOCKED.format(resource));
164 String currentOwner = lockRecord.getOwner();
165 if(!owner.equals(currentOwner)) {
166 throw new LockException(Messages.ERR_UNLOCK_LOCKED_BY_OTHER.format(resource, owner, currentOwner));
168 if (!updateLockRecord(connection, resource, null, 0, lockRecord.getVer())) {
169 unlockResource(connection, resource, owner);
171 // TODO delete record from table on lock release?
172 // deleteLockRecord(connection, resource, lockRecord.getVer());
173 } catch(SQLException e) {
174 throw new LockRuntimeException(Messages.EXP_UNLOCK.format(resource), e);
178 protected LockRecord loadLockRecord(Connection connection, String resource) throws SQLException {
179 LockRecord res = null;
180 if(sqlLoadLockRecord == null) {
181 sqlLoadLockRecord = String.format(SQL_LOAD_LOCK_RECORD, tableName);
183 try(PreparedStatement statement = connection.prepareStatement(sqlLoadLockRecord)) {
184 statement.setString(1, resource);
185 try(ResultSet resultSet = statement.executeQuery()) {
186 if(resultSet.next()) {
187 res = new LockRecord(resource);
188 res.setOwner(resultSet.getString(2));
189 res.setUpdated(resultSet.getLong(3));
190 res.setTimeout(resultSet.getLong(4));
191 res.setVer(resultSet.getLong(5));
198 protected void addLockRecord(Connection connection, String resource, String owner, long timeout) throws SQLException {
199 if(sqlInsertLockRecord == null) {
200 sqlInsertLockRecord = String.format(SQL_INSERT_LOCK_RECORD, tableName);
202 try(PreparedStatement statement = connection.prepareStatement(sqlInsertLockRecord)) {
203 statement.setString(1, resource);
204 statement.setString(2, owner);
205 statement.setLong(3, getCurrentTime(connection));
206 statement.setLong(4, timeout);
207 statement.setLong(5, 1);
208 statement.executeUpdate();
212 protected boolean updateLockRecord(Connection connection, String resource, String owner, long timeout, long ver) throws SQLException {
213 if(sqlUpdateLockRecord == null) {
214 sqlUpdateLockRecord = String.format(SQL_UPDATE_LOCK_RECORD, tableName);
216 try(PreparedStatement statement = connection.prepareStatement(sqlUpdateLockRecord)) {
217 long newVer = (ver >= Long.MAX_VALUE) ? 1 : (ver + 1);
218 statement.setString(1, owner);
219 statement.setLong(2, getCurrentTime(connection));
220 statement.setLong(3, timeout);
221 statement.setLong(4, newVer);
222 statement.setString(5, resource);
223 statement.setLong(6, ver);
224 return (statement.executeUpdate() != 0);
228 // protected void deleteLockRecord(Connection connection, String resource, long ver) throws SQLException {
229 // if(sqlDeleteLockRecord == null) {
230 // sqlDeleteLockRecord = String.format(SQL_DELETE_LOCK_RECORD, tableName);
232 // try(PreparedStatement statement = connection.prepareStatement(sqlDeleteLockRecord)) {
233 // statement.setString(1, resource);
234 // statement.setLong(2, ver);
235 // statement.executeUpdate();
239 private boolean isLockExpired(LockRecord lockRecord, Connection connection) throws SQLException {
240 long timeout = lockRecord.getTimeout();
244 long updated = lockRecord.getUpdated();
245 long now = getCurrentTime(connection);
246 long expiration = updated + timeout;
247 return (now > expiration);
250 private long getCurrentTime(Connection connection) throws SQLException {
252 if(connection != null) {
253 try(PreparedStatement statement = connection.prepareStatement(SQL_CURRENT_TIMESTAMP)) {
254 try(ResultSet resultSet = statement.executeQuery()) {
255 if(resultSet.next()) {
256 res = resultSet.getTimestamp(1).getTime();
262 res = System.currentTimeMillis();