简易图书管理系统（主要是jsp的练习）

package com.bie.dao.impl; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import com.bie.dao.BookDao; import com.bie.po.Book; import com.bie.utils.BaseDao; /** * @author BieHongLi * @version 创建时间：2017年2月23日 上午10:24:02 * */ public class BookDaoImpl implements BookDao{ @Override public List<Book> select(String sql, Object[] arr) { Connection con=null; PreparedStatement ps=null; ResultSet rs=null; try { con=BaseDao.getCon();//第一步连接数据库 ps=con.prepareStatement(sql);//第二步：预编译 if(arr!=null){ for(int i=0;i<arr.length;i++){ ps.setObject(i+1, arr[i]); } } //第四步执行sql rs=ps.executeQuery(); List<Book> list=new ArrayList<Book>(); while(rs.next()){ Book book=new Book(); book.setBookid(rs.getInt("bookid")); book.setBookname(rs.getString("bookname")); book.setPrice(rs.getDouble("price")); book.setAuthor(rs.getString("author")); book.setPic(rs.getString("pic")); book.setPublish(rs.getString("publish")); list.add(book); } return list; } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ //关闭资源，避免出现异常 BaseDao.close(con, ps, rs); } return null; } @Override public Book getBook(Integer id) { Connection con=null; PreparedStatement ps=null; ResultSet rs=null; try { con=BaseDao.getCon();//第一步连接数据库 String sql="select * from book where bookid = ? "; ps=con.prepareStatement(sql);//第二步：预编译 ps.setInt(1, id); //第四步执行sql rs=ps.executeQuery(); while(rs.next()){ Book books=new Book(); books.setBookid(rs.getInt("bookid")); books.setBookname(rs.getString("bookname")); books.setPrice(rs.getDouble("price")); books.setAuthor(rs.getString("author")); books.setPic(rs.getString("pic")); books.setPublish(rs.getString("publish")); return books; } } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ //关闭资源，避免出现异常 BaseDao.close(con, ps, rs); } return null; } @Override public List<Book> bookPage(int page, int record) { Connection con=null; PreparedStatement ps=null; ResultSet rs=null; try { con=BaseDao.getCon();//第一步连接数据库 //第二步书写sql语句 String sql="select * from book limit ?,? "; ps=con.prepareStatement(sql);//第三步：预编译 //第几页需要设置好是页数减一乘以每页的记录数即是第多少页 ps.setInt(1, (page-1)*record); ps.setInt(2, record); //第四步执行sql rs=ps.executeQuery(); List<Book> list=new ArrayList<Book>(); while(rs.next()){ Book book=new Book(); book.setBookid(rs.getInt("bookid")); book.setBookname(rs.getString("bookname")); book.setPrice(rs.getDouble("price")); book.setAuthor(rs.getString("author")); book.setPic(rs.getString("pic")); book.setPublish(rs.getString("publish")); list.add(book); } return list; } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); }finally{ //关闭资源，避免出现异常 BaseDao.close(con, ps, rs); } return null; } @Override public int getCount(int record) { Connection con=null; PreparedStatement ps=null; ResultSet rs=null; //设置初始值为-1 int n=-1; try { con=BaseDao.getCon();//第一步连接数据库 //第二步书写sql语句 String sql="select count(*) from book "; ps=con.prepareStatement(sql);//第三步：预编译 //第四步执行sql rs=ps.executeQuery(); if(rs.next()){ //获取第一条记录，因为查询count(1)就一条记录，获取即可,即总记录数 n=rs.getInt(1); //将总记录数除以每页的总记录数然乎向上取整即可 n=(int)Math.ceil(1.0*n/record); } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); }finally{ //关闭资源，避免出现异常 BaseDao.close(con, ps, rs); } return n; } @Override public boolean insertBook(Book book) { String sql="insert into book values(0,?,?,?,?,?)"; List<Object> list=new ArrayList<Object>(); list.add(book.getBookname()); list.add(book.getPrice()); list.add(book.getAuthor()); list.add(book.getPic()); list.add(book.getPublish()); boolean mark=BaseDao.addUpdateDelete(sql, list.toArray()); if(mark){ return true; }else{ return false; } } @Override public boolean updateBook(Book book) { String sql="update book SET bookname=?,price=?,author=?,pic=?,publish=? where bookid=? "; if(book!=null && book.getBookid()!=null){ List<Object> list=new ArrayList<Object>(); list.add(book.getBookname()); list.add(book.getPrice()); list.add(book.getAuthor()); list.add(book.getPic()); list.add(book.getPublish()); list.add(book.getBookid()); boolean mark=BaseDao.addUpdateDelete(sql, list.toArray()); if(mark){ return true; }else{ return false; } } return false; } @Override public boolean deleteBook(Integer id) { String sql="delete from book where bookid=? "; List<Object> list=new ArrayList<Object>(); list.add(id); boolean mark=BaseDao.addUpdateDelete(sql, list.toArray()); if(mark){ return true; }else{ return false; } } }