DAOFactory - 缺少依赖性

时间:2012-04-07 16:26:51

标签: java jsf jsf-2

我想实现这个example这是到目前为止的代码:

import java.io.Serializable;
import java.math.BigDecimal;
import javax.enterprise.context.SessionScoped;
// or import javax.faces.bean.SessionScoped;
import javax.inject.Named;
/* include SQL Packages */
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.annotation.PostConstruct;
import javax.sql.DataSource;
import javax.annotation.Resource;
import javax.faces.component.UICommand;
import javax.faces.context.FacesContext;
import javax.inject.Inject;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
// or import javax.faces.bean.ManagedBean; 
import javax.faces.event.ActionEvent;

import org.glassfish.osgicdi.OSGiService;

//http://balusc.blogspot.com/2008/10/effective-datatable-paging-and-sorting.html

@Named("SessionsController")
@SessionScoped
public class Sessions implements Serializable {

    /* Call the Oracle JDBC Connection driver */
    @Resource(name = "jdbc/Oracle")
    private DataSource ds;
    // DAO.
    private static ActiveSessionsDAO dao = DAOFactory.getInstance("javabase").getActiveSessionsDAO();
    // Data.
    private List<ActiveSessions> dataList;
    private int totalRows;
    // Paging.
    private int firstRow;
    private int rowsPerPage;
    private int totalPages;
    private int pageRange;
    private Integer[] pages;
    private int currentPage;
    // Sorting.
    private String sortField;
    private boolean sortAscending;
    // Constants ----------------------------------------------------------------------------------
    private static final String SQL_LIST_BY_ORDER_AND_LIMIT =
            "SELECT * FROM ACTIVESESSIONSLOG ORDER BY %s %s LIMIT ?, ?";
    private static final String SQL_COUNT =
            "SELECT count(*) FROM ACTIVESESSIONSLOG";

    private static class DAOFactory {

        public DAOFactory() {
        }
    }

    private static class ActiveSessions {

        public ActiveSessions() {
        }

        private ActiveSessions(long aLong, String string, Integer integer) {
            throw new UnsupportedOperationException("Not yet implemented");
        }
    }
    // Properties ---------------------------------------------------------------------------------
    private DAOFactory daoFactory;

    // Constructors -------------------------------------------------------------------------------

    Sessions(DAOFactory daoFactory) {
        this.daoFactory = daoFactory;
        // Set default values somehow (properties files?).
        rowsPerPage = 10; // Default rows per page (max amount of rows to be displayed at once).
        pageRange = 10; // Default page range (max amount of page links to be displayed at once).
        sortField = "ASESSIONID"; // Default sort field.
        sortAscending = true; // Default sort direction.
    }

    // Paging actions -----------------------------------------------------------------------------
    public void pageFirst() {
        page(0);
    }

    public void pageNext() {
        page(firstRow + rowsPerPage);
    }

    public void pagePrevious() {
        page(firstRow - rowsPerPage);
    }

    public void pageLast() {
        page(totalRows - ((totalRows % rowsPerPage != 0) ? totalRows % rowsPerPage : rowsPerPage));
    }

    public void page(ActionEvent event) {
        page(((Integer) ((UICommand) event.getComponent()).getValue() - 1) * rowsPerPage);
    }

    private void page(int firstRow) {
        this.firstRow = firstRow;
        loadDataList(); // Load requested page.
    }

    // Sorting actions ----------------------------------------------------------------------------
    public void sort(ActionEvent event) {
        String sortFieldAttribute = (String) event.getComponent().getAttributes().get("sortField");

        // If the same field is sorted, then reverse order, else sort the new field ascending.
        if (sortField.equals(sortFieldAttribute)) {
            sortAscending = !sortAscending;
        } else {
            sortField = sortFieldAttribute;
            sortAscending = true;
        }

        pageFirst(); // Go to first page and load requested page.
    }

    // Loaders ------------------------------------------------------------------------------------
    private void loadDataList() {

        // Load list and totalCount.
        try {
            dataList = dao.list(firstRow, rowsPerPage, sortField, sortAscending);
            totalRows = dao.count();
        } catch (Exception e) {
            throw new RuntimeException(e); // Handle it yourself.
        }

        // Set currentPage, totalPages and pages.
        currentPage = (totalRows / rowsPerPage) - ((totalRows - firstRow) / rowsPerPage) + 1;
        totalPages = (totalRows / rowsPerPage) + ((totalRows % rowsPerPage != 0) ? 1 : 0);
        int pagesLength = Math.min(pageRange, totalPages);
        pages = new Integer[pagesLength];

        // firstPage must be greater than 0 and lesser than totalPages-pageLength.
        int firstPage = Math.min(Math.max(0, currentPage - (pageRange / 2)), totalPages - pagesLength);

        // Create pages (page numbers for page links).
        for (int i = 0; i < pagesLength; i++) {
            pages[i] = ++firstPage;
        }
    }

    // Getters ------------------------------------------------------------------------------------
    public List<ActiveSessions> getDataList() {
        if (dataList == null) {
            loadDataList(); // Preload page for the 1st view.
        }
        return dataList;
    }

    public int getTotalRows() {
        return totalRows;
    }

    public int getFirstRow() {
        return firstRow;
    }

    public int getRowsPerPage() {
        return rowsPerPage;
    }

    public Integer[] getPages() {
        return pages;
    }

    public int getCurrentPage() {
        return currentPage;
    }

    public int getTotalPages() {
        return totalPages;
    }

    // Setters ------------------------------------------------------------------------------------
    public void setRowsPerPage(int rowsPerPage) {
        this.rowsPerPage = rowsPerPage;
    }

    // Actions ------------------------------------------------------------------------------------
    /**
     * Returns list of ActiveSessions items starting at the given first index with the given row count,
     * sorted by the given sort field and sort order.
     * @param firstRow First index of rows to be returned.
     * @param rowCount Amount of rows to be returned.
     * @param sortField Field to sort the data on.
     * @param sortAscending Whether to sort data ascending or not.
     * @return list of ActiveSessions items starting at the given first index with the given row count,
     * sorted by the given sort field and sort order.
     * @throws DAOException If something fails at DAO level.
     */
    public List<ActiveSessions> list(int firstRow, int rowCount, String sortField, boolean sortAscending)
            throws Exception {
        Object[] values = {firstRow, rowCount};

        if (ds == null) {
            throw new SQLException();
        }

        String sortDirection = sortAscending ? "ASC" : "DESC";
        String sql = String.format(SQL_LIST_BY_ORDER_AND_LIMIT, sortField, sortDirection);
        Connection conn = ds.getConnection();
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;
        List<ActiveSessions> dataList = new ArrayList<ActiveSessions>();

        try {
            conn.setAutoCommit(false);
            boolean committed = false;
//            connection = daoFactory.getConnection();
            preparedStatement = conn.prepareStatement(sql);
            resultSet = preparedStatement.executeQuery();
            while (resultSet.next()) {
                dataList.add(mapActiveSessions(resultSet));
            }
        } catch (SQLException e) {
            throw new Exception(e);
        } finally {
            conn.close();
        }

        return dataList;
    }

    /**
     * Returns total amount of rows in table.
     * @return Total amount of rows in table.
     * @throws DAOException If something fails at DAO level.
     */
    public int count() throws Exception {
//        Connection connection = null;
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;
        int count = 0;

        try {
//            connection = daoFactory.getConnection();
            Connection conn = ds.getConnection();
            preparedStatement = conn.prepareStatement(SQL_COUNT);
            resultSet = preparedStatement.executeQuery();
            if (resultSet.next()) {
                count = resultSet.getInt(1);
            }
        } catch (SQLException e) {
            throw new Exception(e);
        } finally {
            //close the connection
        }

        return count;
    }

    /**
     * Map the current row of the given ResultSet to ActiveSessions.
     * @param resultSet The ResultSet of which the current row is to be mapped to ActiveSessions.
     * @return The mapped ActiveSessions from the current row of the given ResultSet.
     * @throws SQLException If something fails at database level.
     */
    private static ActiveSessions mapActiveSessions(ResultSet resultSet) throws SQLException {
        return new ActiveSessions(
                resultSet.getLong("ASESSIONID"),
                resultSet.getString("USERID"),
                resultSet.getObject("value") != null ? resultSet.getInt("value") : null);
                /*
                CREATE TABLE ACTIVESESSIONSLOG(
                    ASESSIONID VARCHAR2(30 ) NOT NULL,
                    USERID VARCHAR2(30 ),
                    ACTIVITYSTART TIMESTAMP(6),
                    ACTIVITYEND TIMESTAMP(6),
                    ACTIVITY CLOB
                )
                */
    }
}

我注意到Netbeans在这一行给了我一个错误:

private static ActiveSessionsDAO dao = DAOFactory.getInstance("javabase").getActiveSessionsDAO();

错误消息是:

cannot find symbol
  symbol:   class ActiveSessionsDAO
  location: class com.DX_57.HM_57.Sessions

cannot find symbol
  symbol:   method getInstance(java.lang.String)
  location: class com.DX_57.HM_57.Sessions.DAOFactory

我必须导入哪些依赖项?我可以简化代码并使用简单的JDBC连接从数据库中获取数据吗?

祝福

0 个答案:

没有答案