gerrit.onap Code Review - appc.git/blob

   1 /*-
   2  * ============LICENSE_START=======================================================
   3  * APPC
   4  * ================================================================================
   5  * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
   6  * Copyright (C) 2017 Amdocs
   7  * ================================================================================
   8  * Licensed under the Apache License, Version 2.0 (the "License");
   9  * you may not use this file except in compliance with the License.
  10  * You may obtain a copy of the License at
  11  *
  12  *      http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  * ============LICENSE_END=========================================================
  20  * ECOMP is a trademark and service mark of AT&T Intellectual Property.
  21  */
  22
  23 package org.openecomp.appc.lockmanager.impl.sql.pessimistic;
  24
  25 import java.sql.CallableStatement;
  26 import java.sql.Connection;
  27 import java.sql.ResultSet;
  28 import java.sql.SQLException;
  29
  30 import org.openecomp.appc.lockmanager.api.LockRuntimeException;
  31
  32 public class MySqlLockManager extends SqlLockManager {
  33
  34         private static final int DEF_CRITICAL_SECTION_WAIT_TIMEOUT = 3;
  35
  36         protected int criticalSectionWaitTimeoutSecs = DEF_CRITICAL_SECTION_WAIT_TIMEOUT;
  37
  38         public void setCriticalSectionWaitTimeoutSecs(int criticalSectionWaitTimeoutSecs) {
  39                 this.criticalSectionWaitTimeoutSecs = criticalSectionWaitTimeoutSecs;
  40         }
  41
  42         @Override
  43         protected void enterCriticalSection(Connection connection, String resource) {
  44                 try {
  45                         CallableStatement statement = connection.prepareCall("SELECT COALESCE(GET_LOCK(?,?),0)");
  46                         try {
  47                                 statement.setString(1, resource);
  48                                 statement.setInt(2, criticalSectionWaitTimeoutSecs);
  49                                 boolean execRes = statement.execute();
  50                                 int result = 0;
  51                                 if(execRes) {
  52                                         ResultSet resultSet = statement.getResultSet();
  53                                         try {
  54                                                 if(resultSet.next()) {
  55                                                         result = resultSet.getInt(1);
  56                                                 }
  57                                         } finally {
  58                                                 resultSet.close();
  59                                         }
  60                                 }
  61                                 if(result != 1) { // lock is not obtained
  62                                         throw new LockRuntimeException("Cannot obtain critical section lock for resource [" + resource + "].");
  63                                 }
  64                         } finally {
  65                                 statement.close();
  66                         }
  67                 } catch(SQLException e) {
  68             throw new LockRuntimeException("Cannot obtain critical section lock for resource [" + resource + "].", e);
  69                 }
  70         }
  71
  72         @Override
  73         protected void leaveCriticalSection(Connection connection, String resource) {
  74                 try {
  75                         CallableStatement statement = connection.prepareCall("SELECT RELEASE_LOCK(?)");
  76                         try {
  77                                 statement.setString(1, resource);
  78                                 statement.execute();
  79                         } finally {
  80                                 statement.close();
  81                         }
  82                 } catch(SQLException e) {
  83                         throw new LockRuntimeException("Error releasing critical section lock.", e);
  84                 }
  85         }
  86 }