Code example:
class StudentDAO extends AbstractDAO <Integer, Student> { private static final String SQL_SELECT_ALL_STUDENT = "SELECT ID, FIRST_NAME, SECOND_NAME, BIRTH_DATE,ENTER_YEAR FROM STUDENT"; private static final String SQL_SELECT_STUDENT_BY_ID = "SELECT FIRST_NAME, SECOND_NAME, BIRTH_DATE,ENTER_YEAR FROM STUDENT WHERE ID=?"; private static final String SQL_SELECT_STUDENT_BY_LASTNAME ="SELECT id,FIRST_NAME,BIRTH_DATE,ENTER_YEAR FROM. STUDENT WHERE SECOND_NAME=?"; private static final String SQL_DELETE_STUDENT_BY_ID = "DELETE FROM STUDENT WHERE ID =?"; private static final String SQL_INSERT_STUDENT = "INSERT INTO STUDENT"+"(FIRST_NAME, SECOND_NAME, BIRTH_DATE, ENTER_YEAR)"+"VALUES (?,?,?,?)"; private PreparedStatement preparedStatement1; private PreparedStatement preparedStatementSelectById; private PreparedStatement preparedStatementfindAll; private PreparedStatement preparedStatementDeleteStudentById; private PreparedStatement preparedStatementInsertStudent; public StudentDAO(Connection connection) throws DAOException, SQLException { super(connection); try { preparedStatementInsertStudent =connection.prepareStatement(SQL_INSERT_STUDENT); preparedStatement1 = connection.prepareStatement(SQL_SELECT_STUDENT_BY_LASTNAME); preparedStatementfindAll = connection.prepareStatement(SQL_SELECT_ALL_STUDENT); preparedStatementDeleteStudentById = connection.prepareStatement(SQL_DELETE_STUDENT_BY_ID); preparedStatementSelectById = connection.prepareStatement(SQL_SELECT_STUDENT_BY_ID); } catch (Exception e) { throw new DAOException(e); } } } Difficulties arose in how to close ps when using them in the class constructor?
