frienddbaccess.java

功能描述 1） 后台：管理员负责对整个论坛进行管理

/**
 * 友情链接的增.删.改.查
 */
package bbs.db;

import java.sql.*;
import bbs.bean.BbsFriend;
import com.db.Databasec;
import com.db.face.*;
import java.util.ArrayList;

public class FriendDBAccess
    extends Databasec {
  private java.sql.ResultSet rst;

  /**
   * 插入链接
   * @param friend BbsFriend
   * @return int
   * @throws Exception
   */
  public int insert(BbsFriend friend) throws Exception {
    this.open();
    try {
      String sql = "insert into bbsFriend values('"
          + friend.getFname() + "','"
          + friend.getFaddress() + "')";
      pst = con.prepareStatement(sql);
      return pst.executeUpdate();
    }
    finally {
      this.close();
    }

  }

  /**
   * 删除链接 根据ID号码
   * @param id String
   * @return int
   * @throws Exception
   */
  public int delete(String id) throws Exception {
    try {
      this.open();
      String sql = "delete from bbsFriend where FID=" + id;
      pst = con.prepareStatement(sql);
      return pst.executeUpdate();
    }
    finally {
      this.close();
    }
  }

  /**
   * 更新链接
   * @param friend BbsFriend
   * @return int
   * @throws Exception
   */
  public int update(BbsFriend friend) throws Exception {
    this.open();
    try {
      String sql = "UPDATE bbsFriend SET FName='"
          + friend.getFname() + "', FAddress='"
          + friend.getFaddress() + "' WHERE FID="
          + friend.getFid();
      pst = con.prepareStatement(sql);
      return pst.executeUpdate();
    }
    finally {
      this.close();
    }
  }

  /**
   * 查询链接的方法：
   * @param tabName String
   * @return ArrayList
   * @throws Exception
   */
  public ArrayList select(String tabName) throws Exception {
    return null;
  }

  public ArrayList select() throws Exception {
    ArrayList list = new ArrayList();
    try {
      this.open();
      String sql = "select * from bbsFriend";
      pst = con.prepareStatement(sql);
      rst = pst.executeQuery();
      while (rst.next()) {
        BbsFriend obj = new BbsFriend();
        obj.setFid(rst.getInt("FID"));
        obj.setFname(rst.getString("FName"));
        obj.setFaddress(rst.getString("FAddress"));
        list.add(obj);
      }
    }
    finally {
      this.close();
    }
    return list;
  }

  private int currentPage = 1;
  private int pageCount = 1;
  private int rows = 5;

  public ArrayList select(int page) throws Exception {
    ArrayList list = new ArrayList();
    try {
      this.open();
      String sql = "select count(*) from bbsFriend";
      pst = con.prepareStatement(sql);
      rst = pst.executeQuery();
      rst.next();
      int counts = rst.getInt(1);
      this.close();
      this.pageCount = counts % rows == 0 ? counts / rows : counts / rows + 1;
      if (page > pageCount) {
        page = pageCount;
      }
      if (page < 1) {
        page = 1;
      }
      this.open();
      int pp = (page - 1) * rows;
      sql =  "select top " + rows + " * from bbsFriend "
                + "where fid not in("+ "select top " + pp + " fid from bbsFriend order by fid)"
                + " order by fid";

      pst = con.prepareStatement(sql);
      rst = pst.executeQuery();

      while (rst.next()) {
        BbsFriend obj = new BbsFriend();
        obj.setFid(rst.getInt("FID"));
        obj.setFname(rst.getString("FName"));
        obj.setFaddress(rst.getString("FAddress"));
        list.add(obj);
      }
    }
    finally {
      this.close();
    }
    return list;
  }



  public int getRows() {
    return rows;
  }

  public int getCurrentPage() {
    return currentPage;
  }

  public int getPageCount() {
    return pageCount;
  }

  public void setRows(int rows) {
    this.rows = rows;
  }
}