Code
package dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.util.ArrayList; import util.DBHelper; import entity.Items; //The business logic class of the product public class ItemsDAO { // get all product information public ArrayList<Items> getAllItems() { Connection conn = null; PreparedStatement stmt = null; ResultSet rs = null; ArrayList<Items> list = new ArrayList<Items>(); // 商品集合 try { conn = DBHelper.getConnection(); String sql = "select * from items;"; // SQL语句 stmt = conn.prepareStatement(sql); rs = stmt.executeQuery(); while (rs.next()) { Items item = new Items(); item.setId(rs.getInt("id")); item.setName(rs.getString("name")); item.setCity(rs.getString("city")); item.setNumber(rs.getInt("number")); item.setPrice(rs.getInt("price")); item.setPicture(rs.getString("picture")); list.add(item);// Add an item to the collection } return list; // Return the collection. } catch (Exception ex) { ex.printStackTrace(); return null; } finally { // release the dataset object if (rs != null) { try { rs.close(); rs = null; } catch (Exception ex) { ex.printStackTrace(); } } // release the statement object if (stmt != null) { try { stmt.close(); stmt = null; } catch (Exception ex) { ex.printStackTrace(); } } } } // Get the product information according to the product number public Items getItemsById(int id) { Connection conn = null; PreparedStatement stmt = null; ResultSet rs = null; try { conn = DBHelper.getConnection(); String sql = "select * from items where id=?;"; // SQL语句 stmt = conn.prepareStatement(sql); stmt.setInt(1, id); rs = stmt.executeQuery(); if (rs.next()) { Items item = new Items(); item.setId(rs.getInt("id")); item.setName(rs.getString("name")); item.setCity(rs.getString("city")); item.setNumber(rs.getInt("number")); item.setPrice(rs.getInt("price")); item.setPicture(rs.getString("picture")); return item; } else { return null; } } catch (Exception ex) { ex.printStackTrace(); return null; } finally { // release the dataset object if (rs != null) { try { rs.close(); rs = null; } catch (Exception ex) { ex.printStackTrace(); } } // release the statement object if (stmt != null) { try { stmt.close(); stmt = null; } catch (Exception ex) { ex.printStackTrace(); } } } } //Get the information of the top five items recently browsed public ArrayList<Items> getViewList(String list) { System.out.println("list:"+list); ArrayList<Items> itemlist = new ArrayList<Items>(); int iCount=5; //return the first five records each time if(list!=null&&list.length()>0) { String[] arr = list.split(","); System.out.println("arr.length="+arr.length); //If the product record is greater than or equal to 5 if(arr.length>=5) { for(int i=arr.length-1;i>=arr.length-iCount;i--) { itemlist.add(getItemsById(Integer.parseInt(arr[i]))); } } else { for(int i=arr.length-1;i>=0;i--) { itemlist.add(getItemsById(Integer.parseInt(arr[i]))); } } return itemlist; } else { return null; } } }