001/**
002 * Copyright 2014 Tampere University of Technology, Pori Department
003 * 
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 * 
008 *   http://www.apache.org/licenses/LICENSE-2.0
009 * 
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package core.tut.pori.dao;
017
018import javax.sql.DataSource;
019
020import org.springframework.beans.factory.annotation.Autowired;
021import org.springframework.jdbc.core.JdbcTemplate;
022import org.springframework.jdbc.datasource.DataSourceTransactionManager;
023import org.springframework.transaction.support.TransactionTemplate;
024
025/**
026 * Base class for SQL DAOs.
027 * 
028 * http://dev.mysql.com/doc/refman/5.0/en/connector-j-usagenotes-spring-config.html
029 * http://dev.mysql.com/doc/refman/5.0/en/connector-j-usagenotes-spring-config-jdbctemplate.html
030 * 
031 * Subclassing this class will automatically add the new class to DAOHandler, and will be retrievable
032 * run-time from ServiceInitializer.getDAOHandler().getSQLDAO(...)
033 */
034public abstract class SQLDAO {
035  /* databases */
036  /** default database schema */
037  protected static final String DATABASE = "ca_frontend";
038  /* common columns */
039  /** COUNT(*) definition */
040  protected static final String COLUMN_COUNT = "COUNT(*)";
041  /** default column name for GUIDs */
042  protected static final String COLUMN_GUID = "guid";
043  /** default column name for row created */
044  protected static final String COLUMN_ROW_CREATED = "row_created";
045  /** default column name for row updated */
046  protected static final String COLUMN_ROW_UPDATED = "row_updated";
047  /** default column name for user id */
048  protected static final String COLUMN_USER_ID = "user_id";
049  /* sql strings */
050  /** SQL string for retrieving the last generated row id */
051  protected static final String SQL_SELECT_LAST_INSERT_ID = "SELECT LAST_INSERT_ID()";
052  /* member variables */
053  private JdbcTemplate _jdbcTemplate = null;
054  private TransactionTemplate _transactionTemplate = null;
055  
056  /**
057   * 
058   * @param dataSource
059   */
060  @Autowired
061  public void setDataSource(DataSource dataSource){
062    _jdbcTemplate = new JdbcTemplate(dataSource);
063  }
064  
065  /**
066   * 
067   * @param tnxManager
068   */
069  @Autowired
070  public void setTnxManager(DataSourceTransactionManager tnxManager){
071    _transactionTemplate = new TransactionTemplate(tnxManager);
072  }
073
074  /**
075   * @return the jdbcTemplate
076   */
077  protected JdbcTemplate getJdbcTemplate() {
078    return _jdbcTemplate;
079  }
080  
081  /**
082   * Note: the template is shared amongst all instances that subclass SQLDAO. It is thread-safe, though you should not
083   * change template settings if you are not absolutely sure what you are doing. If a more specific configuration instance
084   * is required, you should instantiate new TransactionTemplate.
085   * 
086   * @return the transactionTemplate
087   */
088  public TransactionTemplate getTransactionTemplate() {
089    return _transactionTemplate;
090  }
091
092  /**
093   * Helper method for checking if the given column is a COUNT(*) column
094   * 
095   * @param columnName
096   * @param value
097   * @return the value of the count column or < 0 if not an count column
098   */
099  protected long checkCountColumn(String columnName, Object value){
100    if(!COLUMN_COUNT.equalsIgnoreCase(columnName)){
101      return -1;
102    }
103    return (Long)value;
104  }
105}