基于jsp+servlet+mysql简单的实现了商品的增删改查(高分课程设计)

package dao; import java.sql.ResultSet; import java.util.ArrayList; import Entity.Product; import jdbc.JDBCUtils; public class ProductDaoImpl implements ProductDao { /** * 插入一个商品 * @param Product * @return */ public boolean insert(Product product) { try { String sql = "insert into product(pno,pname,price,category,num) "+ "values(" + product.getPno() + ",'" + product.getPname() + "'," + product.getPrice() + ",'" + product.getCategory() + "'," +product.getNum() + ")"; boolean flag = JDBCUtils.executeUpdate(sql); return flag; } catch (Exception e) { e.printStackTrace(); } return false; } /** * 查询所有商品数据 * @return */ public ArrayList<Product> findAllProduct() { //定义商品集合 ArrayList<Product> list = new ArrayList<Product>(); try { String sql = "select * from product"; ResultSet rs = JDBCUtils.executeQuery(sql); //循环遍历结果集并放入商品集合中 while (rs.next()) { Product product = new Product(); product.setPno(rs.getInt("pno")); product.setPname(rs.getString("pname")); product.setPrice(rs.getDouble("price")); product.setCategory(rs.getString("category")); product.setNum(rs.getInt("num")); list.add(product); } return list; } catch (Exception e) { e.printStackTrace(); } return null; } // 根据学号查询某个商品（前题学号是唯一） public Product findProductByPno(int pno) { try { String sql = "select * from Product where pno=" + pno; ResultSet rs = JDBCUtils.executeQuery(sql); while (rs.next()) { Product product = new Product(); product.setPno(rs.getInt("pno")); product.setPname(rs.getString("pname")); product.setPrice(rs.getDouble("price")); product.setCategory(rs.getString("category")); product.setNum(rs.getInt("num")); return product; } return null; } catch (Exception e) { e.printStackTrace(); } return null; } /** * 根据学号删除商品 * @param sno 学号 * @return true/false */ public boolean deleteProductByPno(int pno) { try { String sql = "delete from Product where pno=" + pno; boolean flag = JDBCUtils.executeUpdate(sql); return flag; } catch (Exception e) { e.printStackTrace(); } return false; } /** * 更新一个商品信息(根据商品号pno) * @param Product * @return true/false */ public boolean update(Product product) { try { String sql = "update product set pname='" + product.getPname() + "',price="+product.getPrice() + ",category='"+ product.getCategory() + "',num="+product.getNum() +" where pno=" + product.getPno(); boolean flag = JDBCUtils.executeUpdate(sql); return flag; } catch (Exception e) { e.printStackTrace(); } return false; } /** * 带查询条件的查询所有商品数据 * @param p 查询条件 * @return 商品集合 */ public ArrayList<Product> findAllProduct(Product p) { //定义商品集合 ArrayList<Product> list = new ArrayList<Product>(); try { String sql = "select * from product where 1=1 "; if(p.getPname()!=null&&!"".equals(p.getPname())) { sql+="and pname like '%"+p.getPname()+"%'"; } if(p.getCategory()!=null&&!"".equals(p.getCategory())) { sql+="and category ='"+p.getCategory()+"'"; } ResultSet rs = JDBCUtils.executeQuery(sql); //循环遍历结果集并放入商品集合中 while (rs.next()) { Product product = new Product(); product.setPno(rs.getInt("pno")); product.setPname(rs.getString("pname")); product.setPrice(rs.getDouble("price")); product.setCategory(rs.getString("category")); product.setNum(rs.getInt("num")); list.add(product); } return list; } catch (Exception e) { e.printStackTrace(); } return null; } }