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

   1 /**
   2 * Copyright (C) 2007 EDIT
   3 * European Distributed Institute of Taxonomy
   4 * http://www.e-taxonomy.eu
   5 *
   6 * The contents of this file are subject to the Mozilla Public License Version 1.1
   7 * See LICENSE.TXT at the top of this package for the full license terms.
   8 */
   9
  10 package eu.etaxonomy.cdm.database;
  11
  12 import java.sql.Connection;
  13 import java.sql.DriverManager;
  14 import java.sql.ResultSet;
  15 import java.sql.SQLException;
  16 import java.sql.Statement;
  17
  18 import org.apache.log4j.Logger;
  19
  20 import eu.etaxonomy.cdm.database.types.IDatabaseType;
  21
  22 /**
  23  * @author a.mueller
  24  * @created 18.12.2008
  25  * @version 1.0
  26  */
  27 abstract class CdmDataSourceBase implements ICdmDataSource {
  28         private static final Logger logger = Logger.getLogger(CdmDataSourceBase.class);
  29
  30
  31         private Connection getConnection() {
  32
  33                 Connection mConn = null;
  34                 try {
  35                         IDatabaseType dbType = getDatabaseType().getDatabaseType();
  36                         String classString = dbType.getClassString();
  37                         Class.forName(classString);
  38                         String mUrl = dbType.getConnectionString(this);
  39                         mConn = DriverManager.getConnection(mUrl, getUsername(), getPassword());
  40                 } catch (ClassNotFoundException e) {
  41                         logger.error("Database driver class could not be loaded\n" + "Exception: " + e.toString());
  42                 } catch(SQLException e) {
  43                         logger.error("Problems with database connection\n" + "Exception: " + e.toString());
  44                 }
  45                 return mConn;
  46         }
  47
  48
  49         /* (non-Javadoc)
  50          * @see eu.etaxonomy.cdm.database.ICdmDataSource#testConnection()
  51          */
  52         public boolean testConnection() throws DataSourceNotFoundException {
  53
  54                 IDatabaseType dbType = getDatabaseType().getDatabaseType();
  55                 String classString = dbType.getClassString();
  56                 try {
  57                         Class.forName(classString);
  58                         String mUrl = dbType.getConnectionString(this);
  59                         Connection mConn = DriverManager.getConnection(mUrl, getUsername(), getPassword());
  60                         if (mConn != null){
  61                                 return true;
  62                         }
  63                 } catch (ClassNotFoundException e) {
  64                         throw new DataSourceNotFoundException(e);
  65                 } catch (SQLException e) {
  66                         throw new DataSourceNotFoundException(e);
  67                 }
  68                 return false;
  69         }
  70
  71
  72     /**
  73      * Executes a query and returns the ResultSet.
  74      * @return ResultSet for the query.
  75      */
  76         public ResultSet executeQuery (String query) {
  77
  78                 ResultSet rs;
  79                 try {
  80                         if (query == null){
  81                                 return null;
  82                         }
  83                         Connection mConn = getConnection();
  84                         Statement mStmt = mConn.createStatement();
  85                         rs = mStmt.executeQuery(query);
  86                         return rs;
  87                 } catch(SQLException e) {
  88                         logger.error("Problems when executing query \n  " + query + " \n" + "Exception: " + e);
  89                         return null;
  90                 }
  91         }
  92
  93     /**
  94      * Executes an update
  95      * @return return code
  96      */
  97         public int executeUpdate (String sqlUpdate) {
  98
  99                 int result;
 100                 try {
 101                         if (sqlUpdate == null){
 102                                 return 0;
 103                         }
 104                         Connection mConn = getConnection();
 105                         Statement mStmt = mConn.createStatement();
 106                         result = mStmt.executeUpdate(sqlUpdate);
 107                         return result;
 108                 } catch(SQLException e) {
 109                         logger.error("Problems when executing update\n  " + sqlUpdate + " \n" + "Exception: " + e);
 110                         return 0;
 111                 }
 112         }
 113 }