assignmentdaoimpl.java~

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        } catch(SQLException ae) {
            throw new AssignmentDAOSysException("SQLException while getting " +
                      "assignment; id = " + assignmentId + " :\n" + ae);
        } finally {
            closeResultSet(result);
            closeStatement(stmt);
            closeConnection();
        }
    }

    private void deleteassignment (String assignmentId) throws
                                         AssignmentDAODBUpdateException,
                                         AssignmentDAOSysException {
        String queryStr = "DELETE FROM " + DatabaseNames.ASSIGNMENT_TABLE
        + " WHERE assign_ID = " + "'" + assignmentId.trim() + "'";
        PreparedStatement stmt = null;
        Debug.println("queryString is: "+ queryStr);

        try {
            getDBConnection();
            //stmt = dbConnection.createStatement();
            //int resultCount = stmt.executeUpdate(queryStr);
            stmt = createPreparedStatement(dbConnection, queryStr);
            int resultCount = stmt.executeUpdate();

            if (resultCount != 1)
                throw new AssignmentDAODBUpdateException
                ("ERROR deleteing assignment from ASSIGNMENT_TABLE!! resultCount = "+
                 resultCount);
        } catch(SQLException se) {
            throw new AssignmentDAOSysException("SQLException while removing " +
                            "assignment; id = " + assignmentId + " :\n" + se);
        } finally {
            closeStatement(stmt);
            closeConnection();
        }
    }

    private void updateassignment(AssignmentModel assignmentinfo) throws
                                         AssignmentDAODBUpdateException,
                                         AssignmentDAOAppException,
                                         AssignmentDAOSysException {
        if (!isValidData(assignmentinfo))
            throw new AssignmentDAOAppException("Illegal data values for update");

        String queryStr = "UPDATE " + DatabaseNames.ASSIGNMENT_TABLE + " SET "
            +"assign_name = " + "'" + assignmentinfo.getAssign_name().trim() + "',"
            +"task = " + "'" + assignmentinfo.getTask().trim() + "',"
            +"user = " + "'" + assignmentinfo.getUser().trim() + "',"
            +"desc = " + "'" + assignmentinfo.getDesc().trim() + "',"
            +"comment = " + "'" + assignmentinfo.getComment().trim() + "'"
            + " WHERE assign_ID = " + "'" + assignmentinfo.getAssign_ID().trim() + "'";
        Debug.println("queryString is: "+ queryStr);

        PreparedStatement stmt = null;
        try {
            getDBConnection();
            stmt = createPreparedStatement(dbConnection, queryStr);
            int resultCount = stmt.executeUpdate();
            if (resultCount != 1)
                throw new AssignmentDAODBUpdateException
                ("ERROR updating assignment in ASSIGNMENT_TABLE!! resultCount = " +
                 resultCount);
        } catch(SQLException se) {
            throw new AssignmentDAOSysException("SQLException while updating " +
                     "assignment; id = " + assignmentinfo.getAssign_ID() + " :\n" + se);
        } finally {
            closeStatement(stmt);
            closeConnection();
        }
    }

    private void getDBConnection() throws AssignmentDAOSysException {
        try {
            dbConnection = datasource.getConnection();
        } catch (SQLException se) {
            throw new AssignmentDAOSysException("SQL Exception while getting " +
                                "DB connection : \n" + se);
        }
        return;
    }

    private void closeConnection() throws AssignmentDAOSysException {
        try {
            if (dbConnection != null && !dbConnection.isClosed()) {
                dbConnection.close();
        }
        } catch (SQLException se) {
            throw new AssignmentDAOSysException("SQL Exception while closing " +
                                        "DB connection : \n" + se);
        }
    }

    private void closeResultSet(ResultSet result) throws AssignmentDAOSysException {
        try {
            if (result != null) {
                result.close();
            }
        } catch (SQLException se) {
            throw new AssignmentDAOSysException("SQL Exception while closing " +
                                        "Result Set : \n" + se);
        }
    }

    private void closeStatement(PreparedStatement stmt) throws AssignmentDAOSysException {
        try {
            if (stmt != null) {
                stmt.close();
            }
        } catch (SQLException se) {
            throw new AssignmentDAOSysException("SQL Exception while closing " +
                                        "Statement : \n" + se);
        }
    }
    
    public Collection findAll() throws
    AssignmentDAOFinderException,
    AssignmentDAOSysException {
        PreparedStatement stmt = null;
        ResultSet result = null;
        AssignmentModel tmodel = null;
        boolean returnValue = false;
        ArrayList results = new ArrayList();
        String queryStr ="SELECT * FROM " +
        DatabaseNames.ASSIGNMENT_TABLE;
        Debug.println("queryString is: "+ queryStr);
        try {
            getDBConnection();
            stmt = createPreparedStatement(dbConnection, queryStr);
            result = stmt.executeQuery();
            while(result.next()) {
                                tmodel = new AssignmentModel(result.getString(1),result.getString(2), result.getString(3),result.getString(4),
                                       result.getString(5), result.getString(6));
                results.add(tmodel);
            }
        } catch(SQLException se) {
            throw new AssignmentDAOSysException(
            "SQLException while selecting"
            + " existing all assignment  -> "  + " :\n" + se);
        } finally {
            closeResultSet(result);
            closeStatement(stmt);
            closeConnection();
        }
        return (results);
    }

    public Collection findByField(String fieldname, String fieldkey) throws
    AssignmentDAOFinderException,
    AssignmentDAOSysException {
        PreparedStatement stmt = null;
        ResultSet result = null;
        AssignmentModel tmodel = null;
        boolean returnValue = false;
        ArrayList results = new ArrayList();
        String queryStr ="SELECT * FROM " +
        DatabaseNames.ASSIGNMENT_TABLE
        + " WHERE "+fieldname+" = " + "'" + fieldkey.trim() + "'";
        Debug.println("queryString is: "+ queryStr);
        
        try {
            getDBConnection();
            stmt = createPreparedStatement(dbConnection, queryStr);
            result = stmt.executeQuery();
            while(result.next()) {                
                tmodel = new AssignmentModel(result.getString(1),result.getString(2), result.getString(3),result.getString(4),
                                       result.getString(5), result.getString(6));

                results.add(tmodel);
            }
        } catch(SQLException se) {
            throw new AssignmentDAOSysException(
            "SQLException while selecting"
            + " existing task " + fieldname + " -> " + fieldkey + " :\n" + se);
        } finally {
            closeResultSet(result);
            closeStatement(stmt);
            closeConnection();
        }
        return (results);
    }


    /**
     * This method allows us to create a prepared search statement that will be friendly
     * To Japanese in cloudscape and other databases.
     * Basically we use a prepared statement that contants '?' where Japanese characters
     * may occur and then we use the stmt.setString(index, "search string")
     *
     * This technique should not affect the English searchs.
     *
    */

    private PreparedStatement createPreparedStatement(Connection con, String querry)
            throws SQLException {
        ArrayList targetStrings = new ArrayList();
        String processedQuerry = "";
        int startIndex = 0;
        if (startIndex != -1) {
            int index = startIndex;
            int literalStart = -1;
            while (index < querry.length()) {
                if (querry.charAt(index) == '\'') {
                    if (literalStart == -1 && index + 1 < querry.length()) {
                        literalStart = index +1;
                    } else {
                        String targetString = querry.substring(literalStart, index);
                        targetStrings.add(targetString);
                        literalStart = -1;
                        processedQuerry += "?";
                        index++;
                    }
                }
               if (index < querry.length() && literalStart == -1) {
                    processedQuerry += querry.charAt(index);
                }
                index++;
            }
            PreparedStatement stmt = con.prepareStatement(processedQuerry + " ");
            Iterator it = targetStrings.iterator();
            int counter =1;
            while (it.hasNext()) {
                String arg = (String)it.next();
                stmt.setString(counter++, arg);
            }
            return stmt;
        } else {
            PreparedStatement stmt = con.prepareStatement(querry);
            return stmt;
        }
    }
}