先在MySql中建一个数据库其中包含三个表，一个book表，一个user表，一个info表
jsp界面只输入图书号，按图书号还书，续借，预约
JavaBean中写了book类，info类，user类，数据库连接类，还有一个时间类
book类
package bean;
public class Book {
private String id;
private String name;
private String author;
private double price;
private String info;
public Book(String id, String name, String author, double price, String info) {
this.id = id;
this.name = name;
this.author = author;
this.price = price;
this.info = info;
}
public Book() {}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public String getInfo() {
return info;
}
public void setInfo(String info) {
this.info = info;
}
}
info类
package bean;
public class Info {
private String id;
private String name;
private String uname;
private String type;
private String lendate;
private String huanqi;
private String cq;
private String info;
private String appoint;
public Info() {}
public Info(String id, String name, String uname, String type, String lendate, String huanqi, String cq,
String info, String appoint) {
this.id = id;
this.name = name;
this.uname = uname;
this.type = type;
this.lendate = lendate;
this.huanqi = huanqi;
this.cq = cq;
this.info = info;
this.appoint = appoint;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getUname() {
return uname;
}
public void setUname(String uname) {
this.uname = uname;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getLendate() {
return lendate;
}
public void setLendate(String lendate) {
this.lendate = lendate;
}
public String getHuanqi() {
return huanqi;
}
public void setHuanqi(String huanqi) {
this.huanqi = huanqi;
}
public String getCq() {
return cq;
}
public void setCq(String cq) {
this.cq = cq;
}
public String getInfo() {
return info;
}
public void setInfo(String info) {
this.info = info;
}
public String getAppoint() {
return appoint;
}
public void setAppoint(String appoint) {
this.appoint = appoint;
}
}
user类
package bean;
public class User {
private String uname;
private String password;
private String info;
public User() {}
public User(String uname, String password, String info) {
this.uname = uname;
this.password = password;
this.info = info;
}
public String getUname() {
return uname;
}
public void setUname(String uname) {
this.uname = uname;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getInfo() {
return info;
}
public void setInfo(String info) {
this.info = info;
}
}
数据库连接类（可作为模板，任何使用JDBC都可以建此类，调用即可）
package bean;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class SJKLJ {
private static String driverName="com.mysql.jdbc.Driver";
private static String userName="root";
private static String userPwd="root";
private static String dbName="bookmanage";
public static Connection getDBconnection() {
String url1="jdbc:mysql://localhost:3306/"+dbName;
String url2="?user="+userName+"&password="+userPwd;
String url3="&useUnicode=true&characterEncoding=GB2312";
String url=url1+url2+url3;
try {
Class.forName(driverName);
Connection conn=DriverManager.getConnection(url);
return conn;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static void closeB(Connection conn,PreparedStatement pstmt,ResultSet rs) {
try {
if(rs!=null)rs.close();
if(pstmt!=null) pstmt.close();
if(conn!=null) conn.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
时间类（其中包含借书，续借，和超期的时间，我只用到了续借）
package bean;
import java.text.SimpleDateFormat;
import java.util.*;
public class Date_d {
private String now;
public String now_time() {
// SimpleDateFormat format = new SimpleDateFormat("yyyy-mm-dd");
Calendar calendar = Calendar.getInstance();
int cur_month=calendar.get(Calendar.MONTH)+1;
int cur_year=calendar.get(Calendar.YEAR);
int cur_day=calendar.get(Calendar.DAY_OF_MONTH);
now = cur_year+"-"+cur_month+"-"+cur_day;
return now;
}
public String huanq() {
Calendar calendar = Calendar.getInstance();
int cur_month=calendar.get(Calendar.MONTH)+2;
int cur_year=calendar.get(Calendar.YEAR);
int cur_day=calendar.get(Calendar.DAY_OF_MONTH);
now = cur_year+"-"+cur_month+"-"+cur_day;
return now;
}
public String Xujie() {
Calendar calendar = Calendar.getInstance();
int cur_month=calendar.get(Calendar.MONTH)+3;
int cur_year=calendar.get(Calendar.YEAR);
int cur_day=calendar.get(Calendar.DAY_OF_MONTH);
now = cur_year+"-"+cur_month+"-"+cur_day;
return now;
}
@SuppressWarnings("unused")
public long chaoq(String bl) throws Exception {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
//开始时间
Date startDate = sdf.parse(bl);
//结束时间
Date endDate = sdf.parse(this.now_time());///
//得到相差的天数 betweenDate
long betweenDate = (endDate.getTime() - startDate.getTime())/(60*60*24*1000);
return betweenDate;
}
}
servlet类，我只写了查询id，三个功能的servlet是一样的，只是跳转到的jsp名不一样
Dao中写了，查找id，还书时（更新book的info为可借，更新info表的info为已还），续借时（只需将info表的huanqi加一个月即可），预约时（更新book表的info为不可预约，更新info表的appoint的信息为已被预约）
package Dao;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import bean.Book;
import bean.Date_d;
import bean.Info;
import bean.SJKLJ;
public class Dao {
public List<Info> select(String id) throws Exception{
String sql="select id,name,uname,type,lendate,huanqi,cq,info,appoint from info where id="+id;
Connection conn=null;
PreparedStatement pstmt=null;
ResultSet rs=null;
List<Info> list=new ArrayList<Info>();
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
rs=pstmt.executeQuery();
rs.last();
if(rs.getRow()!=0) {
rs.beforeFirst();
while(rs.next()) {
String id1=rs.getString("id");
String name=rs.getString("name");
String uname=rs.getString("uname");
String type=rs.getString("type");
String lendate=rs.getString("lendate");
String huanqi=rs.getString("huanqi");
String cq=rs.getString("cq");
String info=rs.getString("info");
String appoint=rs.getString("appoint");
Info in=new Info(id1,name,uname,type,lendate,huanqi,cq,info,appoint);
list.add(in);
}
}
SJKLJ.closeB(conn, pstmt, rs);
return list;
}
public int update_b(String id) throws Exception{
String sql="update book set info = '可借' where id = "+id;
Connection conn=null;
PreparedStatement pstmt=null;
int n=0;
@SuppressWarnings("unused")
String m=null;
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
n=pstmt.executeUpdate();
SJKLJ.closeB(conn, pstmt, null);
return n;
}
public int update_i(String id) throws Exception{
String sql="update info set info ='已还' where id ="+id;
Connection conn=null;
PreparedStatement pstmt=null;
int n=0;
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
n=pstmt.executeUpdate() ;
SJKLJ.closeB(conn, pstmt, null);
return n;
}
public int update_in(String id)throws Exception{
Date_d dd=new Date_d();
String now=dd.Xujie();
String sql="update info set huanqi='"+now+"' where id="+id;
Connection conn=null;
PreparedStatement pstmt=null;
int n=0;
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
n=pstmt.executeUpdate() ;
SJKLJ.closeB(conn, pstmt, null);
return n;
}
public int update_bo(String id)throws Exception{
String sql="update book set info='不可预约' where id="+id;
Connection conn=null;
PreparedStatement pstmt=null;
int n=0;
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
n=pstmt.executeUpdate() ;
SJKLJ.closeB(conn, pstmt, null);
return n;
}
public int update_inf(String id)throws Exception{
String sql="update info set appoint='已被预约' where id="+id;
Connection conn=null;
PreparedStatement pstmt=null;
int n=0;
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
n=pstmt.executeUpdate() ;
SJKLJ.closeB(conn, pstmt, null);
return n;
}
public List<Book> select_b(String id)throws Exception{
String sql="select id,name,author,price,info from book where id="+id;
Connection conn=null;
PreparedStatement pstmt=null;
ResultSet rs=null;
conn=SJKLJ.getDBconnection();
pstmt=conn.prepareStatement(sql);
rs=pstmt.executeQuery();
rs.last();
List<Book> list=new ArrayList<Book>();
if(rs.getRow()!=0) {
rs.beforeFirst();
while(rs.next()) {
String id1=rs.getString("id");
String name=rs.getString("name");
String author=rs.getString("author");
Double price=rs.getDouble("price");
String info=rs.getString("info");
Book bb=new Book(id1,name,author,price,info);
list.add(bb);
}
}
SJKLJ.closeB(conn, pstmt, null);
return list;
}
}
最后的show.jsp中，还书和预约相似，续借更为简单
还书：
<%@ page language="java" import="bean.*" import="java.util.*" import="Dao.Dao"
import="java.sql.*" import="bean.SJKLJ" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
Dao d=new Dao();
//System.out.println("111");
@SuppressWarnings("unchecked")
List<Info> list=(List<Info>)session.getAttribute("list");
if(list.get(0).getInfo().equals("")){
//System.out.println("444");
//System.out.println(list.get(0).getId());
int nn=d.update_i(list.get(0).getId());
//System.out.println("222");
if(nn==1){
int mm=d.update_b(list.get(0).getId());
if(mm==1){
%>还书成功！<%
}else{
%>还书失败，出现异常错误！<%
}
}
}else{
%>您已经还过此书！<%
}
%>
</body>
</html>
续借：
<%@ page language="java" import="bean.*" import="Dao.Dao" import="java.util.*" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
Dao d=new Dao();
System.out.println("222");
@SuppressWarnings("unchecked")
List<Info> list=(List<Info>)session.getAttribute("list");
System.out.println("333");
int m=d.update_in(list.get(0).getId());
System.out.println("444");
if(m==1){
System.out.println("555");
//Date_d dd=new Date_d();
//String hq=dd.huanq();
%>续借成功！续借时间为30天，请按时还书！<%
}else{
%>续借失败！<%
}
%>
</body>
</html>
预约：
<%@ page language="java" import="bean.*" import="java.util.*" import="Dao.Dao"
import="java.sql.*" import="bean.SJKLJ" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
Dao d=new Dao();
@SuppressWarnings("unchecked")
List<Book> list=(List<Book>)session.getAttribute("list");
if(list.get(0).getInfo().equals("预约")){
//System.out.println("444");
//System.out.println(list.get(0).getId());
int nn=d.update_inf(list.get(0).getId());
//System.out.println("222");
if(nn==1){
%>预约成功！<%
}else{
%>出现异常错误！<%
}
}else{
%>预约失败！<%
}
%>
</body>
</html>
想要添加其他的功能只需在Dao里添加即可！
