cdmlib-persistence/src/main/java/eu/etaxonomy/cdm/database/update/TableDroper.java

   1 // $Id$
   2 /**
   3 * Copyright (C) 2009 EDIT
   4 * European Distributed Institute of Taxonomy
   5 * http://www.e-taxonomy.eu
   6 *
   7 * The contents of this file are subject to the Mozilla Public License Version 1.1
   8 * See LICENSE.TXT at the top of this package for the full license terms.
   9 */
  10 package eu.etaxonomy.cdm.database.update;
  11
  12 import org.apache.log4j.Logger;
  13
  14 import eu.etaxonomy.cdm.common.monitor.IProgressMonitor;
  15 import eu.etaxonomy.cdm.database.DatabaseTypeEnum;
  16 import eu.etaxonomy.cdm.database.ICdmDataSource;
  17
  18 /**
  19  * @author a.mueller
  20  * @date 16.09.2010
  21  *
  22  */
  23 public class TableDroper extends AuditedSchemaUpdaterStepBase<TableDroper> implements ISchemaUpdaterStep {
  24         private static final Logger logger = Logger.getLogger(TableDroper.class);
  25
  26         private boolean ifExists = true;
  27
  28         public static final TableDroper NewInstance(String stepName, String tableName, boolean includeAudTable){
  29                 return new TableDroper(stepName, tableName, includeAudTable, true);
  30         }
  31
  32         /**
  33          * @param stepName
  34          * @param tableName
  35          * @param includeAudTable
  36          * @param ifExists if false, and error will be thrown if the table does not exist and can therefore not be dropped.
  37          * @see #NewInstance(String, String, boolean)
  38          * @return
  39          */
  40         public static final TableDroper NewInstance(String stepName, String tableName, boolean includeAudTable, boolean ifExists){
  41                 return new TableDroper(stepName, tableName, includeAudTable, ifExists);
  42         }
  43
  44
  45         protected TableDroper(String stepName, String tableName, boolean includeAudTable, boolean ifExists) {
  46                 super(stepName);
  47                 this.tableName = tableName;
  48                 this.includeAudTable = includeAudTable;
  49                 this.ifExists = ifExists;
  50         }
  51
  52         @Override
  53         protected boolean invokeOnTable(String tableName, ICdmDataSource datasource, IProgressMonitor monitor, CaseType caseType) {
  54                 boolean result = true;
  55                 try {
  56                         String updateQuery = getUpdateQueryString(tableName, datasource, monitor);
  57                         datasource.executeUpdate(updateQuery);
  58                         if (! this.isAuditing){
  59                                 removeFromHibernateSequences(datasource, monitor, tableName);
  60                         }
  61                         return result;
  62                 } catch ( Exception e) {
  63                         monitor.warning(e.getMessage(), e);
  64                         logger.error(e);
  65                         return false;
  66                 }
  67         }
  68
  69         private boolean removeFromHibernateSequences(ICdmDataSource datasource, IProgressMonitor monitor, String tableName) {
  70                 try {
  71                         //TODO do we need to "case" this table name?
  72                         String sql = " DELETE FROM hibernate_sequences WHERE sequence_name = '%s'";
  73                         sql = String.format(sql, tableName);
  74                         datasource.executeUpdate(sql);
  75                         return true;
  76                 } catch (Exception e) {
  77                         String message = "Exception occurred when trying to read or update hibernate_sequences table for value " + this.tableName + ": " + e.getMessage();
  78                         monitor.warning(message, e);
  79                         logger.error(message);
  80                         return false;
  81                 }
  82
  83         }
  84
  85         /**
  86          * @param tableName cased tableName
  87          * @param datasource
  88          * @param monitor
  89          * @param caseType
  90          * @return
  91          * @throws DatabaseTypeNotSupportedException
  92          */
  93         public String getUpdateQueryString(String tableName, ICdmDataSource datasource, IProgressMonitor monitor) throws DatabaseTypeNotSupportedException {
  94                 String updateQuery;
  95                 DatabaseTypeEnum type = datasource.getDatabaseType();
  96
  97                 updateQuery = "DROP TABLE @ifExists @tableName ";
  98                 if (type.equals(DatabaseTypeEnum.SqlServer2005)){
  99                         //MySQL allows both syntaxes
 100                         updateQuery = " if exists (select * from INFORMATION_SCHEMA.TABLES where TABLE_NAME='@tableName') BEGIN drop table @tableName end ";
 101                 }else if (type.equals(DatabaseTypeEnum.H2) || type.equals(DatabaseTypeEnum.PostgreSQL) || type.equals(DatabaseTypeEnum.MySQL)){
 102 //                      updateQuery = "ALTER TABLE @tableName @addSeparator @columnName @columnType";
 103                 }else{
 104                         updateQuery = null;
 105                         String warning = "Update step '" + this.getStepName() + "' is not supported by " + type.getName();
 106                         monitor.warning(warning);
 107                         throw new DatabaseTypeNotSupportedException(warning);
 108                 }
 109                 updateQuery = updateQuery.replace("@tableName", tableName);
 110                 if (ifExists == true){
 111                         updateQuery = updateQuery.replace("@ifExists", "IF EXISTS");
 112                 }else{
 113                         updateQuery = updateQuery.replace("@ifExists", "");
 114                 }
 115
 116                 return updateQuery;
 117         }
 118
 119
 120 }