JSP+Servlet实现购物车功能

最近期末的JSP要交大作业，我选择的是做一个在线购物书店,实现登陆注册购物车结算的功能。

一.项目总览以及使用的JS组件框架:

捕获.JPG

根据项目结构 知道用的是DAO设计模式，然后使用了 JS组件库SUI,然后看看项目完成以后大概是这样.
引导页

引导页.gif

注册

注册.gif

登陆

登陆.gif

图书列表

图书列表 (1).gif

图书详情以及购物车

图书详情以及购物车.gif

结算

结算.gif

二.数据库设计以及代码实现

user_profile表:实现登陆注册

user_profile表.JPG

book_details表:实现图书列表以及图书详情

book_details表.JPG

payment表:实现结算

payment表.JPG

然后是代码:首先是根据数据库表生成的实体类:
UserProfile:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package pack;

import java.io.Serializable;
import java.util.Collection;
import javax.persistence.Basic;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlTransient;

/**
 *
 * @author sl
 */
@Entity
@Table(name = "user_profile")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "UserProfile.findAll", query = "SELECT u FROM UserProfile u")
    , @NamedQuery(name = "UserProfile.findByIdUserProfile", query = "SELECT u FROM UserProfile u WHERE u.idUserProfile = :idUserProfile")
    , @NamedQuery(name = "UserProfile.findByUsername", query = "SELECT u FROM UserProfile u WHERE u.username = :username")
    , @NamedQuery(name = "UserProfile.findByPassword", query = "SELECT u FROM UserProfile u WHERE u.password = :password")
    , @NamedQuery(name = "UserProfile.findByFirstname", query = "SELECT u FROM UserProfile u WHERE u.firstname = :firstname")
    , @NamedQuery(name = "UserProfile.findByMiddlename", query = "SELECT u FROM UserProfile u WHERE u.middlename = :middlename")
    , @NamedQuery(name = "UserProfile.findByLastname", query = "SELECT u FROM UserProfile u WHERE u.lastname = :lastname")
    , @NamedQuery(name = "UserProfile.findByAddress1", query = "SELECT u FROM UserProfile u WHERE u.address1 = :address1")
    , @NamedQuery(name = "UserProfile.findByAddress2", query = "SELECT u FROM UserProfile u WHERE u.address2 = :address2")
    , @NamedQuery(name = "UserProfile.findByCity", query = "SELECT u FROM UserProfile u WHERE u.city = :city")
    , @NamedQuery(name = "UserProfile.findByState", query = "SELECT u FROM UserProfile u WHERE u.state = :state")
    , @NamedQuery(name = "UserProfile.findByPincode", query = "SELECT u FROM UserProfile u WHERE u.pincode = :pincode")
    , @NamedQuery(name = "UserProfile.findByEmail", query = "SELECT u FROM UserProfile u WHERE u.email = :email")
    , @NamedQuery(name = "UserProfile.findByPhone", query = "SELECT u FROM UserProfile u WHERE u.phone = :phone")})
public class UserProfile implements Serializable {

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "username")
    private Collection paymentCollection;

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "idUser_Profile")
    private Integer idUserProfile;
    @Basic(optional = false)
    @Column(name = "username")
    private String username;
    @Basic(optional = false)
    @Column(name = "password")
    private String password;
    @Basic(optional = false)
    @Column(name = "firstname")
    private String firstname;
    @Basic(optional = false)
    @Column(name = "middlename")
    private String middlename;
    @Basic(optional = false)
    @Column(name = "lastname")
    private String lastname;
    @Basic(optional = false)
    @Column(name = "address1")
    private String address1;
    @Basic(optional = false)
    @Column(name = "address2")
    private String address2;
    @Basic(optional = false)
    @Column(name = "city")
    private String city;
    @Basic(optional = false)
    @Column(name = "state")
    private String state;
    @Basic(optional = false)
    @Column(name = "pincode")
    private String pincode;
    @Basic(optional = false)
    @Column(name = "email")
    private String email;
    @Basic(optional = false)
    @Column(name = "phone")
    private int phone;

    public UserProfile() {
    }

    public UserProfile(Integer idUserProfile) {
        this.idUserProfile = idUserProfile;
    }

    public UserProfile(Integer idUserProfile, String username, String password, String firstname, String middlename, String lastname, String address1, String address2, String city, String state, String pincode, String email, int phone) {
        this.idUserProfile = idUserProfile;
        this.username = username;
        this.password = password;
        this.firstname = firstname;
        this.middlename = middlename;
        this.lastname = lastname;
        this.address1 = address1;
        this.address2 = address2;
        this.city = city;
        this.state = state;
        this.pincode = pincode;
        this.email = email;
        this.phone = phone;
    }

    public Integer getIdUserProfile() {
        return idUserProfile;
    }

    public void setIdUserProfile(Integer idUserProfile) {
        this.idUserProfile = idUserProfile;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getFirstname() {
        return firstname;
    }

    public void setFirstname(String firstname) {
        this.firstname = firstname;
    }

    public String getMiddlename() {
        return middlename;
    }

    public void setMiddlename(String middlename) {
        this.middlename = middlename;
    }

    public String getLastname() {
        return lastname;
    }

    public void setLastname(String lastname) {
        this.lastname = lastname;
    }

    public String getAddress1() {
        return address1;
    }

    public void setAddress1(String address1) {
        this.address1 = address1;
    }

    public String getAddress2() {
        return address2;
    }

    public void setAddress2(String address2) {
        this.address2 = address2;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getState() {
        return state;
    }

    public void setState(String state) {
        this.state = state;
    }

    public String getPincode() {
        return pincode;
    }

    public void setPincode(String pincode) {
        this.pincode = pincode;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public int getPhone() {
        return phone;
    }

    public void setPhone(int phone) {
        this.phone = phone;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (idUserProfile != null ? idUserProfile.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof UserProfile)) {
            return false;
        }
        UserProfile other = (UserProfile) object;
        if ((this.idUserProfile == null && other.idUserProfile != null) || (this.idUserProfile != null && !this.idUserProfile.equals(other.idUserProfile))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "pack.UserProfile[ idUserProfile=" + idUserProfile + " ]";
    }

    @XmlTransient
    public Collection getPaymentCollection() {
        return paymentCollection;
    }

    public void setPaymentCollection(Collection paymentCollection) {
        this.paymentCollection = paymentCollection;
    }
    
}

BookDetails:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package pack;

import java.io.Serializable;
import java.util.Collection;
import javax.persistence.Basic;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlTransient;

/**
 *
 * @author sl
 */
@Entity
@Table(name = "book_details")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "BookDetails.findAll", query = "SELECT b FROM BookDetails b")
    , @NamedQuery(name = "BookDetails.findByIdBookDetails", query = "SELECT b FROM BookDetails b WHERE b.idBookDetails = :idBookDetails")
    , @NamedQuery(name = "BookDetails.findByCategoryName", query = "SELECT b FROM BookDetails b WHERE b.categoryName = :categoryName")
    , @NamedQuery(name = "BookDetails.findByBookId", query = "SELECT b FROM BookDetails b WHERE b.bookId = :bookId")
    , @NamedQuery(name = "BookDetails.findByTitle", query = "SELECT b FROM BookDetails b WHERE b.title = :title")
    , @NamedQuery(name = "BookDetails.findByAuthor", query = "SELECT b FROM BookDetails b WHERE b.author = :author")
    , @NamedQuery(name = "BookDetails.findByPublisher", query = "SELECT b FROM BookDetails b WHERE b.publisher = :publisher")
    , @NamedQuery(name = "BookDetails.findByIsbn", query = "SELECT b FROM BookDetails b WHERE b.isbn = :isbn")
    , @NamedQuery(name = "BookDetails.findByPrice", query = "SELECT b FROM BookDetails b WHERE b.price = :price")
    , @NamedQuery(name = "BookDetails.findByDescription", query = "SELECT b FROM BookDetails b WHERE b.description = :description")})
public class BookDetails implements Serializable {

    @Basic(optional = false)
    @Column(name = "pic")
    private String pic;

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "idBook_Details")
    private Integer idBookDetails;
    @Basic(optional = false)
    @Column(name = "category_name")
    private String categoryName;
    @Basic(optional = false)
    @Column(name = "book_id")
    private int bookId;
    @Basic(optional = false)
    @Column(name = "title")
    private String title;
    @Basic(optional = false)
    @Column(name = "author")
    private String author;
    @Basic(optional = false)
    @Column(name = "publisher")
    private String publisher;
    @Basic(optional = false)
    @Column(name = "isbn")
    private String isbn;
    @Basic(optional = false)
    @Column(name = "price")
    private int price;
    @Column(name = "description")
    private String description;
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "bookId")
    private Collection billTableCollection;

    public BookDetails() {
    }

    public BookDetails(Integer idBookDetails) {
        this.idBookDetails = idBookDetails;
    }

    public BookDetails(Integer idBookDetails, String categoryName, int bookId, String title, String author, String publisher, String isbn, int price) {
        this.idBookDetails = idBookDetails;
        this.categoryName = categoryName;
        this.bookId = bookId;
        this.title = title;
        this.author = author;
        this.publisher = publisher;
        this.isbn = isbn;
        this.price = price;
    }

    public Integer getIdBookDetails() {
        return idBookDetails;
    }

    public void setIdBookDetails(Integer idBookDetails) {
        this.idBookDetails = idBookDetails;
    }

    public String getCategoryName() {
        return categoryName;
    }

    public void setCategoryName(String categoryName) {
        this.categoryName = categoryName;
    }

    public int getBookId() {
        return bookId;
    }

    public void setBookId(int bookId) {
        this.bookId = bookId;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public String getPublisher() {
        return publisher;
    }

    public void setPublisher(String publisher) {
        this.publisher = publisher;
    }

    public String getIsbn() {
        return isbn;
    }

    public void setIsbn(String isbn) {
        this.isbn = isbn;
    }

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    @XmlTransient
    public Collection getBillTableCollection() {
        return billTableCollection;
    }

    public void setBillTableCollection(Collection billTableCollection) {
        this.billTableCollection = billTableCollection;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (idBookDetails != null ? idBookDetails.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof BookDetails)) {
            return false;
        }
        BookDetails other = (BookDetails) object;
        if ((this.idBookDetails == null && other.idBookDetails != null) || (this.idBookDetails != null && !this.idBookDetails.equals(other.idBookDetails))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "pack.BookDetails[ idBookDetails=" + idBookDetails + " ]";
    }

    public String getPic() {
        return pic;
    }

    public void setPic(String pic) {
        this.pic = pic;
    }
    
}

Payment:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package pack;

import java.io.Serializable;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;

/**
 *
 * @author sl
 */
@Entity
@Table(name = "payment")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Payment.findAll", query = "SELECT p FROM Payment p")
    , @NamedQuery(name = "Payment.findByIdPayment", query = "SELECT p FROM Payment p WHERE p.idPayment = :idPayment")
    , @NamedQuery(name = "Payment.findByTotalAmount", query = "SELECT p FROM Payment p WHERE p.totalAmount = :totalAmount")
    , @NamedQuery(name = "Payment.findByCreditcardNum", query = "SELECT p FROM Payment p WHERE p.creditcardNum = :creditcardNum")
    , @NamedQuery(name = "Payment.findByCreditcardType", query = "SELECT p FROM Payment p WHERE p.creditcardType = :creditcardType")})
public class Payment implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @Basic(optional = false)
    @Column(name = "idPayment")
    private Integer idPayment;
    @Basic(optional = false)
    @Column(name = "total_amount")
    private int totalAmount;
    @Basic(optional = false)
    @Column(name = "creditcard_num")
    private int creditcardNum;
    @Basic(optional = false)
    @Column(name = "creditcard_type")
    private int creditcardType;
    @JoinColumn(name = "bill_num", referencedColumnName = "bill_num")
    @ManyToOne(optional = false)
    private BillTable billNum;
    @JoinColumn(name = "username", referencedColumnName = "username")
    @ManyToOne(optional = false)
    private UserProfile username;

    public Payment() {
    }

    public Payment(Integer idPayment) {
        this.idPayment = idPayment;
    }

    public Payment(Integer idPayment, int totalAmount, int creditcardNum, int creditcardType) {
        this.idPayment = idPayment;
        this.totalAmount = totalAmount;
        this.creditcardNum = creditcardNum;
        this.creditcardType = creditcardType;
    }

    public Integer getIdPayment() {
        return idPayment;
    }

    public void setIdPayment(Integer idPayment) {
        this.idPayment = idPayment;
    }

    public int getTotalAmount() {
        return totalAmount;
    }

    public void setTotalAmount(int totalAmount) {
        this.totalAmount = totalAmount;
    }

    public int getCreditcardNum() {
        return creditcardNum;
    }

    public void setCreditcardNum(int creditcardNum) {
        this.creditcardNum = creditcardNum;
    }

    public int getCreditcardType() {
        return creditcardType;
    }

    public void setCreditcardType(int creditcardType) {
        this.creditcardType = creditcardType;
    }

    public BillTable getBillNum() {
        return billNum;
    }

    public void setBillNum(BillTable billNum) {
        this.billNum = billNum;
    }

    public UserProfile getUsername() {
        return username;
    }

    public void setUsername(UserProfile username) {
        this.username = username;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (idPayment != null ? idPayment.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Payment)) {
            return false;
        }
        Payment other = (Payment) object;
        if ((this.idPayment == null && other.idPayment != null) || (this.idPayment != null && !this.idPayment.equals(other.idPayment))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "pack.Payment[ idPayment=" + idPayment + " ]";
    }
    
}

工具类util包下的数据库连接类BaseDao:

package util;

 import java.sql.Connection;
  import java.sql.DriverManager;
  import java.sql.PreparedStatement;
  import java.sql.ResultSet;
  import java.sql.SQLException;
/**
 *
 * @author sl
 */
public class BaseDao {
     private static String driver="com.mysql.jdbc.Driver";
      private static String url="jdbc:mysql://localhost/mydb";
      private static String user="***";
     private static String password="******";//这里数据库账号密码就不贴了
     
      /***
 22      * 连接数据库的方法
 23      * @return
 24      * @throws ClassNotFoundException
 25      * @throws SQLException
 26      */
     public static Connection getCon() throws ClassNotFoundException, SQLException{
          Class.forName(driver);//加载数据库驱动
          System.out.println("测试加载数据库成功");
        Connection con=DriverManager.getConnection(url, user, password);
         System.out.println("测试数据库链接成功");
         return con;
     }
  
     /***
 36      * 关闭数据库的方法
 37      * @param con
 38      * @param ps
 39      * @param rs
 40      */
      public static void close(Connection con,PreparedStatement ps,ResultSet rs){
         if(rs!=null){//关闭资源，避免出现异常
             try {
                 rs.close();
             } catch (SQLException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
              }
         }
         if(ps!=null){
             try {
                 ps.close();
             } catch (SQLException e) {
                 // TODO Auto-generated catch block
                  e.printStackTrace();
              }
         }
          if(con!=null){
             try {
                 con.close();
             } catch (SQLException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
              }
         }
      }
      
      /***
 69      * 同意增删改的方法
 70      * @param sql
 71      * @param arr
 72      * @return
 73      */
      public static boolean addUpdateDelete(String sql,Object[] arr){
          Connection con=null;
          PreparedStatement ps=null;
          try {
              con=BaseDao.getCon();//第一步 ：连接数据库的操作
             ps=con.prepareStatement(sql);//第二步：预编译
              //第三步：设置值
              if(arr!=null && arr.length!=0){
                  for(int i=0;i0){
                 return true;
              }else{
                  return false;
              }
          } catch (ClassNotFoundException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          } catch (SQLException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          }
          return false;
     }
     //测试用例
//     public static void main(String[] args) {
//         try {
//             BaseDao.getCon();
//         } catch (ClassNotFoundException e) {
//             // TODO Auto-generated catch block
//             e.printStackTrace();
//         } catch (SQLException e) {
//             // TODO Auto-generated catch block
//             e.printStackTrace();
//         }
//     }
}

然后书DAO数据层的Book类以及User类的接口以及回调方法实现:
BookDao：

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package dao;

import java.util.List;
import pack.BookDetails;

/**
 *
 * @author sl
 */
public interface BookDao {
       /***
15      * 图书的查询的方法
16      * @param sql
17      * @param arr
18      * @return
19      */
     public List select(String sql,Object[] arr);
     
     /***
23      * 按照图书编号进行查询
24      * @param id
25      * @return
26      */
     public BookDetails getBook(Integer id);
     
     public List getBooks(String category);
     
     public List queryAll();
}

BookDaoImpl:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package dao;

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 pack.BookDetails;
import util.BaseDao;

/**
 *
 * @author sl
 */
public class BookDaoImpl implements BookDao{
     @Override
     public List 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 list=new ArrayList();
              while(rs.next()){
                  BookDetails book=new BookDetails();
                  book.setBookId(rs.getInt("book_id"));
                  book.setTitle(rs.getString("title"));
                  book.setAuthor(rs.getString("author"));
                  book.setPublisher(rs.getString("publisher"));
                  book.setIsbn(rs.getString("isbn"));
                  book.setPrice(rs.getInt("price"));
                  book.setPic(rs.getString("pic"));
                  book.setCategoryName("category_name");
                  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;
      }
     
  //根据书的ID查找书本
      @Override
      public BookDetails 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_details where book_id = ? ";
              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()){
                  BookDetails books=new BookDetails();
                  books.setBookId(rs.getInt("book_id"));
                  books.setTitle(rs.getString("title"));
                  books.setAuthor(rs.getString("author"));
                  books.setPublisher(rs.getString("publisher"));
                  books.setIsbn(rs.getString("isbn"));
                  books.setPrice(rs.getInt("price"));
                  books.setPic(rs.getString("pic"));
                   books.setCategoryName("category_name");
                  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;
      }
//根据书的类型查找书本
    @Override
    public List getBooks(String category) {
       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_details where category_name = ? ";
              ps=con.prepareStatement(sql);//第二步：预编译
              ps.setString(1, category);
              
              //第四步执行sql
              rs=ps.executeQuery();
               List list=new ArrayList();
              while(rs.next()){
                  BookDetails books=new BookDetails();
                  books.setBookId(rs.getInt("book_id"));
                  books.setTitle(rs.getString("title"));
                  books.setAuthor(rs.getString("author"));
                  books.setPublisher(rs.getString("publisher"));
                  books.setIsbn(rs.getString("isbn"));
                  books.setPrice(rs.getInt("price"));
                  books.setPic(rs.getString("pic"));
                   books.setCategoryName("category_name");
                  list.add(books);
              }
              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 List queryAll() {
           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_details";
              ps=con.prepareStatement(sql);//第二步：预编译
             
              
              //第四步执行sql
              rs=ps.executeQuery();
             List list=new ArrayList();
              while(rs.next()){
                  BookDetails books=new BookDetails();
                  books.setBookId(rs.getInt("book_id"));
                  books.setTitle(rs.getString("title"));
                  books.setAuthor(rs.getString("author"));
                  books.setPublisher(rs.getString("publisher"));
                  books.setIsbn(rs.getString("isbn"));
                  books.setPrice(rs.getInt("price"));
                  books.setPic(rs.getString("pic"));
                   books.setCategoryName("category_name");
                  list.add(books);
              }
              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;
    }
      
    
      
}

UserDao:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package dao;

import java.util.List;
import pack.UserProfile;

/**
 *
 * @author sl
 */
public interface UserDao {
    //用户登陆方法声明/回调声明 查询的方法都是返回的对象 返回查询的对象 或者是list对象或者是VO类对象
    public UserProfile login(UserProfile user);
    //用户注册方法声明/回调声明 //增加更新删除的方法 插入的方法都是返回一个布尔值 成功或者失败
    public boolean register(UserProfile user);
    //查询用户的信息
    public ListselectUser(String sql,Object[]arr);
}

UserDaoImpl:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import pack.UserProfile;
import util.BaseDao;

/**
 *
 * @author sl
 */
public class UserDaoImpl implements UserDao{
    //数据库的连接都要try catch 不同的是 查询的方法要在数据层DAO层写 增删改则可以借助工具类中 封装好的try catch
    //回调方法 登陆
    @Override
    public UserProfile login(UserProfile user) {//传入一个有用户名和密码的对象 如果查询到了 就返回 没有对象为null
           Connection connection=null;//数据库连接类
           PreparedStatement ps=null;//执行sql语句
           ResultSet rs=null;//返回的结果
           try {
                //1.获取数据库连接
            connection=BaseDao.getCon();
                //2.书写sql语句
                String sql="SELECT * FROM user_profile WHERE username=? AND password=?";
                //3.预编译
                ps=connection.prepareStatement(sql);
                //4.设置查询条件
                ps.setString(1, user.getUsername());
                ps.setString(2, user.getPassword());
                //5.执行sql语句 返回结果集
                rs=ps.executeQuery();
                UserProfile users=null;
                if(rs.next()){
                //数据库返回的数据与vo类进行交互
                users=new UserProfile();
                users.setUsername(rs.getString("username"));
                users.setPassword(rs.getString("password"));
                users.setPhone(rs.getInt("phone"));
                //....还有一些值
                return users;
                }else{
                return  null;
                }
            
        } catch (Exception e) {
            e.printStackTrace();
        }finally{
               //关闭资源 避免出现异常
               BaseDao.close(connection, ps, rs);
           }
           return null;
    }

    //回调方法 注册
    @Override
    public boolean register(UserProfile user) {
         String sql = "INSERT INTO user_profile(username, password, firstname, middlename, lastname, address1, address2, city, state, pincode, email, phone) "  
                + "VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)";  
          List