1.创建项目，配置tomcat

创建项目
配置tomcat

2.测试项目能否启动

3.创建WEB-INF依赖，导入jar包

导jar
创建WEB-INF依赖

4.编写数据库脚本，利用IDEA建表

连接数据库
建表

--------------------------------------------------------------------
--                创建库，表，约束，过程，用户，权限等脚本
----------------------------------------------------------------------create database res;CREATE DATABASE res DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;use res;create table resadmin(raid int primary key auto_increment,raname varchar(50),rapwd  varchar(50)
);create table resuser(userid int  primary key auto_increment,username varchar(50),pwd varchar(50), email varchar(500)
);--normprice:原价  realprice:现价   description:简介 detail详细的
create table resfood(fid int  primary key auto_increment,fname varchar(50) ,  normprice numeric(8,2),realprice numeric(8,2),detail varchar(2000),fphoto varchar(1000)
);
--订单表:   roid:订单号    userid:外键，下单的用户编号    ordertime:下单时间   uname:收货人姓名    deliverytype:送货方式   payment:支付方式, ps附言
create table resorder(roid int  primary key auto_increment,userid int,address varchar(500),tel varchar( 100),ordertime date,deliverytime date,ps varchar( 2000),status int
);
--订单表的下单人号与用户表中的客户编号有主外键关系.
alter table resorderadd constraint fk_resorderforeign key(userid) references resuser(userid);--dealprice:成交价   roid:订单号   fid:商品号  num:数量
create table resorderitem(roiid int  primary key auto_increment,roid  int,fid   int,dealprice numeric(8,2),num     int
);alter table resorderitem add constraint fk_resorderitem_roidforeign key(roid) references resorder( roid);alter table resorderitemadd constraint fk_tbl_res_fidforeign key( fid ) references resfood( fid);commit;

use res;
insert into resadmin(raname,rapwd) values( 'a','0cc175b9c0f1b6a831c399e269772661');
select * from resadmin;
---用户表初始数据
insert into resuser( username, pwd,email) values( 'a', '0cc175b9c0f1b6a831c399e269772661','a@163.com');
insert into resuser( username, pwd,email) values( 'b', '0cc175b9c0f1b6a831c399e269772661','b@163.com');--插入菜
insert into resfood(fname,normprice,realprice,detail, fphoto)  values('素炒莴笋丝',22.0,20.0,'营养丰富','500008.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)  values('蛋炒饭',22.0,20.0,'营养丰富','500022.jpg');
insert into resfood( fname,normprice,realprice,detail, fphoto)  values('酸辣鱼',42.0,40.0,'营养丰富','500023.jpg');
insert into resfood( fname,normprice,realprice,detail, fphoto)  values('鲁粉',12.0,10.0,'营养丰富','500024.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)  values('西红柿蛋汤',12.0,10.0,'营养丰富','500025.jpg');insert into resfood(fname,normprice,realprice,detail, fphoto)   values('炖鸡',102.0,100.0,'营养丰富','500026.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)  values('炒鸡',12.0,10.0,'营养丰富','500033.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)   values('炒饭',12.0,10.0,'营养丰富','500034.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)   values('手撕前女友',12.0,10.0,'营养丰富','500035.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)  values('面条',12.0,10.0,'营养丰富','500036.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)  values('端菜',12.0,10.0,'营养丰富','500038.jpg');
insert into resfood(fname,normprice,realprice,detail, fphoto)   values('酸豆角',12.0,10.0,'营养丰富','500041.jpg');--不测试:   生成一条订单   a用户订了  1号菜1份,及2号菜2份
insert into resorder(userid,address,tel,ordertime,deliverytime,ps,status)
values( 1,'湖南省衡阳市','13878789999',now(),now(),'送餐上门',0);insert into resorderitem(roid,fid,dealprice,num)
values( 1,1,20,1);insert into resorderitem(roid,fid,dealprice,num)
values( 1,2,20,1);
--注意以上的三条语句要求在事务中处理.
commit; select * from resuser;

5.创建包，即创建项目架构

6.写项目

1.commons

db.properties——mysql

driver_name=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/res?characterEncoding=utf-8
user=root
password=aaaa//mysql数据库密码

db.properties——oracle

driver_name=oracle.jdbc.driver.OracleDriver
url=jdbc:oracle:thin:@localhost:1521:orcl
user=scott
password=a

MyProperties

public class MyProperties extends Properties {//懒汉单例  防止实例未初始化public static MyProperties instance = new MyProperties();private MyProperties(){try {this.load(this.getClass().getClassLoader().getResourceAsStream("com/yc/commons/db.properties"));} catch (IOException e) {e.printStackTrace();}}public static MyProperties getInstince(){return instance;}
}

DbHelper

public class DbHelper {//驱动加载static{try {Class.forName(MyProperties.getInstince().getProperty("driver_name"));} catch (ClassNotFoundException e) {e.printStackTrace();}}//全局变量private Connection conn;private Statement stmt;private PreparedStatement pstmt;private ResultSet rs;//获取连接对象 Connection connpublic Connection getConn(){try {Properties p = MyProperties.getInstince();conn = DriverManager.getConnection(p.getProperty("url"),p);} catch (SQLException e) {System.out.println("获取连接对象失败："+e.getMessage());e.printStackTrace();}return conn;}//获取 Statement stmtpublic Statement getStmt(){try {stmt = conn.createStatement();} catch (SQLException e) {e.printStackTrace();}return stmt;}//关闭所有资源型public void closeAll(Connection conn,Statement pstmt,ResultSet rs){if(rs!=null){try {rs.close();} catch (SQLException e) {e.printStackTrace();}}if(pstmt!=null){try {pstmt.close();} catch (SQLException e) {e.printStackTrace();}}if(conn!=null){try {conn.close();} catch (SQLException e) {e.printStackTrace();}}}//给sql设置参数public void setParams(PreparedStatement pstmt,Object...params) throws Exception{if(params==null||params.length<=0){return ;}for(int i=0;i<params.length;i++){pstmt.setObject(i+1, params[i]);}}//单条sql语句更新public int update(String sql,Object...params) throws Exception{int result=0;try {conn=getConn();pstmt=conn.prepareStatement(sql);setParams(pstmt, params);result=pstmt.executeUpdate();} catch (SQLException e) {e.printStackTrace();System.out.println("单条更新异常："+e.getMessage());throw e;//将异常抛出到调用部分，这样可以将错误信息显示在客户端}finally {closeAll(conn, pstmt, null);}return result;}/*** 多条更新sql语句(带了事务的更新操作)*/public int update(List<String> sqls,List<List<Object>> params) throws Exception{int result = 0;try {conn=getConn();//将事务设为手动处理，即关闭隐式事务提交conn.setAutoCommit(false);//循环所有的sql语句for(int i=0;i<sqls.size();i++){//获取单条sql语句String sql = sqls.get(i);//获取与sql语句对应位置的参数设置ListList<Object> param = params.get(i);pstmt=conn.prepareStatement(sql);//设置参数setParams(pstmt, param.toArray());//将集合转为对象数组result=pstmt.executeUpdate();if(result<=0){//更新受影响的函数认为更新失败，撤销前面所有的操作conn.rollback();return result;}}//执行成功——手动提交事务conn.commit();//一次性将所有的事务提交} catch (SQLException e) {//事务回滚conn.rollback();result=0;e.printStackTrace();System.out.println("多条更新异常："+e.getMessage());throw e;}finally {//事务还原conn.setAutoCommit(true);closeAll(conn, pstmt, null);}return result;}//获取所有列名public List<String> getColumnNames(ResultSet rs) throws SQLException{List<String> colunmNames = new ArrayList<String>();//通过结果集对象获取结果集所有的列及属性ResultSetMetaData data = rs.getMetaData();// 获取此 ResultSet 对象的列的编号、类型和属性int count = data.getColumnCount();//根据sql语句查看列的条数//System.out.println(count);//列的编号从1开始for(int i=1;i<=count;i++){colunmNames.add(data.getColumnName(i));}//System.out.println(colunmNames);return colunmNames;}//获取 T 对象中所有的set方法private List<Method> getAllSetMethod(Class cls){List<Method> setMethods = new ArrayList<Method>();Method[] methods = cls.getMethods();for (Method m:methods){if (m.getName().startsWith("set")){//如果set开头setMethods.add(m);}}return setMethods;}//将 Map 中的数据转存到 T 对象private <T>T parseMapToT(Class<T> cls,Map<String,Object> map) throws Exception{T t = cls.newInstance();//2.从cls中取出所有的set方法，设置值List<Method> setMethods = getAllSetMethod(cls);//3.循环取键值for (Map.Entry<String,Object> entry : map.entrySet()){String key = entry.getKey().toString();Object values = entry.getValue();for (Method m:setMethods){if(m.getName().equalsIgnoreCase("set"+key)){//依次取出每个参数的类型  setXXX的参数String typeName = m.getParameterTypes()[0].getTypeName();if("int".equalsIgnoreCase(typeName) || "java.lang.Integer".equalsIgnoreCase(typeName)){m.invoke(t,Integer.parseInt(values.toString()));}else if("long".equalsIgnoreCase(typeName) || "java.lang.Long".equalsIgnoreCase(typeName)){m.invoke(t,Long.parseLong(values.toString()));}else if("float".equalsIgnoreCase(typeName) || "java.lang.Float".equalsIgnoreCase(typeName)){m.invoke(t,Float.parseFloat(values.toString()));}else if("double".equalsIgnoreCase(typeName) || "java.lang.Double".equalsIgnoreCase(typeName)){m.invoke(t,Double.parseDouble(values.toString()));}else if("boolean".equalsIgnoreCase(typeName) || "java.lang.Boolean".equalsIgnoreCase(typeName)){m.invoke(t,Boolean.parseBoolean(values.toString()));}else {m.invoke(t,values.toString());}break;}}}return t;}//返回一条记录查询操作public Map<String,Object> findSingle(String sql,Object...params) throws Exception{Map<String,Object> map=null;try {conn=getConn();pstmt=conn.prepareStatement(sql);setParams(pstmt, params);//给？设置参数//返回结果集对象rs = pstmt.executeQuery();//获取所有的列名List<String> columnNames=getColumnNames(rs);if(rs.next()){map = new HashMap<String,Object>();for(String name:columnNames){//根据名称获取值Object obj = rs.getObject(name);if(obj==null)continue;//获取当前值的数据类型String typeName = obj.getClass().getName();//数据库不擅长存BLOB和CLOB等大数据,性能太差-->每种服务器的使用场景不同，尽量避免使用短板map.put(name, rs.getObject(name));}}} catch (SQLException e) {e.printStackTrace();System.out.println("单条查询异常："+e.getMessage());throw e;}finally {closeAll(conn, pstmt, rs);}return map;}//单条查询到的 Map 结果转成 T 对象public <T>T findSingle(Class<T> cls,String sql,Object...params) throws Exception{Map<String,Object> map = findSingle(sql,params);return parseMapToT(cls,map);}//返回多条记录查询操作public List<Map<String,Object>> findMutipl(String sql,Object...params)throws Exception{Map<String,Object> map=null;List<Map<String,Object>> list=new ArrayList<Map<String,Object>>();try {conn=getConn();pstmt=conn.prepareStatement(sql);setParams(pstmt, params);rs = pstmt.executeQuery();List<String> columnNames=getColumnNames(rs);//System.out.println(columnNames);//多条数据while(rs.next()){map = new HashMap<String,Object>();for(String name:columnNames){//根据名称获取值Object obj = rs.getObject(name);//System.out.println(obj);if(obj==null)continue;//获取当前值的数据类型String typeName = obj.getClass().getName();map.put(name, rs.getObject(name));}list.add(map);//System.out.println("list:"+list);}} catch (SQLException e) {e.printStackTrace();System.out.println("单条查询异常："+e.getMessage());throw e;}finally {closeAll(conn, pstmt, rs);}return list;}//单条查询到的 List 结果转成 T 对象后再次封装到 List返回public <T>List<T> findMutipl(Class<T> cls,String sql,Object...params)throws Exception{List<Map<String,Object>> list = findMutipl(sql,params);List<T> listT = new ArrayList<T>();for (Map<String,Object> map:list){listT.add(parseMapToT(cls,map));}return listT;}//聚合函数查询  单个聚合函数 select count(*) from 表名public double getPloymer(String sql,Object...params) throws Exception{double result=0;try {conn=getConn();pstmt=conn.prepareStatement(sql);setParams(pstmt, params);rs=pstmt.executeQuery();if(rs.next()){result=rs.getDouble(1);//double 的形式获取此 ResultSet 对象的当前行中指定列的值   列1}} catch (SQLException e) {e.printStackTrace();throw new Exception("聚合函数查询失败："+e.getMessage());}finally{closeAll(conn, pstmt, rs);}return result;}
}

Encrypt

/**- 加密工具类- md5加密出来的长度是32位- sha加密出来的长度是40位*/
public class Encrypt {/*** 测试*/public static void main(String[] args) {// md5加密测试   单向加密 没办法恢复成原来密码  但是容易破解String md5_1 = md5("a");String md5_2 = md5("1");System.out.println(md5_1 + "\n" + md5_2);// sha加密测试  单向加密 没办法恢复成原来密码    但是容易破解String sha_1 = sha("a");String sha_2 = sha("1");System.out.println(sha_1 + "\n" + sha_2);//破解  ->   彩虹表 (通过加密出来的密码是固定的 , 网上可以查到)//0cc175b9c0f1b6a831c399e269772661      a//c4ca4238a0b923820dcc509a6f75849b     1//升级： 加盐     多次加密//54f74fbfb94518a527a36474dc904c25     aSystem.out.println( md5( md5( md5("a" ) ) ) );//多次加密//5eb03b8172b979cd387f25e26982b313       aSystem.out.println( md5( sha( md5("a" ) ) ) );//混合加密//应用价值:  因为使用md5和sha加密得到的结果是不一样的(散列效果),所以可以用于制作指纹.识别文件.}/*** 加密** @param inputText* @return*/public static String e(String inputText) {return md5(inputText);}/*** 二次加密，应该破解不了了吧？* @param inputText* @return*/public static String md5AndSha(String inputText) {return sha(md5(inputText));}/*** md5加密* @param inputText* @return*/public static String md5(String inputText) {return encrypt(inputText, "md5");}/*** sha加密* @param inputText* @return*/public static String sha(String inputText) {return encrypt(inputText, "sha-1");}/*** md5或者sha-1加密** @param inputText*            要加密的内容* @param algorithmName*            加密算法名称：md5或者sha-1，不区分大小写* @return*/private static String encrypt(String inputText, String algorithmName) {if (inputText == null || "".equals(inputText.trim())) {throw new IllegalArgumentException("请输入要加密的内容");}if (algorithmName == null || "".equals(algorithmName.trim())) {algorithmName = "md5";}String encryptText = null;try {MessageDigest m = MessageDigest.getInstance(algorithmName);m.update(inputText.getBytes("UTF8"));byte s[] = m.digest();// m.digest(inputText.getBytes("UTF8"));return hex(s);} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (UnsupportedEncodingException e) {e.printStackTrace();}return encryptText;}/*** 返回十六进制字符串* @param arr* @return*/private static String hex(byte[] arr) {StringBuffer sb = new StringBuffer();for (int i = 0; i < arr.length; ++i) {sb.append(Integer.toHexString((arr[i] & 0xFF) | 0x100).substring(1, 3));}return sb.toString();}
}

DataDict

/**- 中间数据类   数据字典类*/
public class DataDict {//保存session中用户信息的键名     方便修改   方便使用public static final String RESUSER="resuser";//购物车public static final String CART="cart";//下单状态public static final Integer ORDER_STATUS_ORDERED=1;
}

2.bean

JsonModel

/*** JSON回送数据模型，将数据包装成一个对象在转成json字符串** implements Serializable：序列化接口*/
public class JsonModel implements Serializable {private Integer code;//是否出错private String msg;//出错之后的异常信息private Object data;//数据public void setCode(Integer code) {this.code = code;}public void setMsg(String msg) {this.msg = msg;}public void setData(Object data) {this.data = data;}public Integer getCode() {return code;}public String getMsg() {return msg;}public Object getData() {return data;}
}

3.biz

OrderConfirm

/**- 自动生成的列的插法和Oracle不同*/
public class OrderConfirm {public void confirm(Resorder resorder, Map<Integer, CartItem> cart) throws Exception {DbHelper dbHelper = new DbHelper();Connection con = dbHelper.getConn();//关闭隐式事务try {con.setAutoCommit(false);String sql = "insert into resorder(userid,address,tel,ordertime,deliverytime,ps,status) values( ?,?,?,now(),?,?,?)";PreparedStatement pstmt = con.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);pstmt.setString(1,resorder.getUserid()+"");pstmt.setString(2,resorder.getAddress()+"");pstmt.setString(3,resorder.getTel()+"");pstmt.setString(4,resorder.getDeliverytime()+"");pstmt.setString(5,resorder.getPs()+"");pstmt.setString(6,resorder.getStatus()+"");pstmt.executeUpdate();Integer roid = null;//获取自动生成的订单号ResultSet rs = pstmt.getGeneratedKeys();if(rs.next()){roid = rs.getInt(1);}if(roid==null){throw new Exception("订单添加失败");}//循环添加订单详情for (Map.Entry<Integer,CartItem> entry:cart.entrySet()){int fid = entry.getKey();CartItem ci = entry.getValue();Resfood resfood = ci.getResfood();int num = ci.getNum();double smallCount = ci.getSmallCount();String sql2 = "insert into resorderitem(roid,fid,dealprice,num) values(?,?,?,?)";PreparedStatement pstmt2 = con.prepareStatement(sql2);pstmt2.setString(1,roid+"");pstmt2.setString(2,resfood.getFid()+"");pstmt2.setString(3,resfood.getRealprice()+"");pstmt2.setString(4,num+"");pstmt2.executeUpdate();}con.commit();}catch (Exception e) {con.rollback();e.printStackTrace();throw e;}finally {if(con!=null && con.isClosed()==false){con.setAutoCommit(true);con.close();}}}
}

4.web/servlets

CommonServlet（封装提升）

/*通用工具类=====abstract  不能直接用调用顺序1.构造块 构造方法 init()  service()  super.service()  doGet()/doPost()2.                      service()  super.service()  doGet()/doPost()有错==》看是哪一端的错误客户端：在开发者工具服务端：看自己的代码*/public abstract class CommonServlet extends HttpServlet {/*** 每次生命周期一定会执行这个，调用一次===》设置编码*/@Overrideprotected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {req.setCharacterEncoding("utf-8");//必须在super.service(req, resp);的前面执行// 本来在doGet()/doPost()中执行==>此处封装的话若在super.service(req, resp);之后则顺序是//super.service()  doGet()/doPost()   req.setCharacterEncoding("utf-8"); ====》 这样设置的话就晚了super.service(req, resp);//不能删  删除了之后改生命周期以及之后的都不会执行//生命周期执行流程}@Overrideprotected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doPost(request,response);}/*** 判断使用哪个函数*/@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {/*** 解决请求分发*///1.取出请求的路径  yc108_showall/*String pathInfo = req.getPathInfo();System.out.println(pathInfo);//   /show*///String methodName = pathInfo.substring(1);String methodName = req.getParameter("op");//3.激活下面对应的方法//不要采用if-else方=====>太死//策略模式   解决很多if-else问题//拿到这个类中所有的方法，判断这个方法名==methodName//反射Method[] methods = this.getClass().getDeclaredMethods();//getDeclaredMethods()获取本类中的方法//getMethods()只能不到publicboolean isFindPage = false;for (Method m:methods){if(m.getName().equals(methodName)){try {m.setAccessible(true);//设置私有方法的访问权限：可以被访问m.invoke(this,req,resp);//激活方法(哪个对象,参数1,参数2)isFindPage = true;} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}}}if(isFindPage==false){out404(resp);}}/*** 报错* @param resp* @throws IOException*/protected void out404(HttpServletResponse resp) throws IOException {resp.setContentType("text/html;charset=utf-8");PrintWriter out = resp.getWriter();out.println("404");out.close();}/*** 获取界面中的参数，并存入到一个对应的类中保存* 返回一个将参数设置成对应界面信息的类** <T>T  ===  限定类的类型必须为T*    上限  <? extends E>*    下线  <? super E>* Class<T> cls === 一个类的对象T   相当于List<String>*/protected <T>T parseRequest(Class<T> cls,HttpServletRequest req) throws IllegalAccessException, InstantiationException, InvocationTargetException {//cls创建一个对象T t = cls.newInstance();//1.从request中取出所有参数Map<String,String[]> map = req.getParameterMap();//2.从cls中取出所有的set方法，设置值List<Method> setMethods = getAllSetMethod(cls);//3.循环取键值for (Map.Entry<String,String[]> entry : map.entrySet()){String key = entry.getKey().toString();String[] values = entry.getValue();for (Method m:setMethods){if(m.getName().equalsIgnoreCase("set"+key)){//依次取出每个参数的类型  setXXX的参数String typeName = m.getParameterTypes()[0].getTypeName();if("int".equalsIgnoreCase(typeName) || "java.lang.Integer".equalsIgnoreCase(typeName)){m.invoke(t,Integer.parseInt(values[0]));}else if("long".equalsIgnoreCase(typeName) || "java.lang.Long".equalsIgnoreCase(typeName)){m.invoke(t,Long.parseLong(values[0]));}else if("float".equalsIgnoreCase(typeName) || "java.lang.Float".equalsIgnoreCase(typeName)){m.invoke(t,Float.parseFloat(values[0]));}else if("double".equalsIgnoreCase(typeName) || "java.lang.Double".equalsIgnoreCase(typeName)){m.invoke(t,Double.parseDouble(values[0]));}else if("boolean".equalsIgnoreCase(typeName) || "java.lang.Boolean".equalsIgnoreCase(typeName)){m.invoke(t,Boolean.parseBoolean(values[0]));}else {m.invoke(t,values[0]);}break;}}}return t;}/*** 获取T对象中所有的set函数* @param cls* @return*/private List<Method> getAllSetMethod(Class cls){List<Method> setMethods = new ArrayList<Method>();Method[] methods = cls.getMethods();for (Method m:methods){if (m.getName().startsWith("set")){//如果set开头setMethods.add(m);}}return setMethods;}/*** 将jsonmodel转为json的字符串，并利用response输出到客户端*/protected void writeJson(JsonModel jm, HttpServletResponse response) throws IOException {//1.jm对象转成json字符串//第三方框架：将对象转为 json字符串  gson(google)  fastjson(alibaba)Gson gson = new Gson();String json = gson.toJson(jm);//2.通过responce将json字符串写到页面上//application/json   文件类型由http协议规范   在tomcat安装目录/conf/web.xml中找到对应的描述response.setContentType("application/json;charset=utf-8");PrintWriter out = response.getWriter();out.println(json);out.close();}}

custOpServlet

@WebServlet("/custOp.action")
public class custOpServlet extends CommonServlet {private void confirmOrder(HttpServletRequest request, HttpServletResponse response) throws IOException {/*String address = request.getParameter("address");String tel = request.getParameter("tel");String deliverytime = request.getParameter("deliverytime");String ps = request.getParameter("ps");*/JsonModel jsonModel = new JsonModel();try {//读取参数Resorder resorder = super.parseRequest(Resorder.class,request);//获取用户idHttpSession session = request.getSession();Resuser resuser = (Resuser) session.getAttribute(DataDict.RESUSER);resorder.setUserid(resuser.getUserid());resorder.setStatus(DataDict.ORDER_STATUS_ORDERED);//取出购物车Map<Integer, CartItem> cart = (Map<Integer, CartItem>) session.getAttribute(DataDict.CART);//插入数据到数据库OrderConfirm oc = new OrderConfirm();oc.confirm(resorder,cart);//下单成功 购物车清空session.removeAttribute(DataDict.CART);jsonModel.setCode(1);} catch (Exception e) {jsonModel.setCode(0);jsonModel.setMsg(e.getMessage());e.printStackTrace();}super.writeJson(jsonModel,response);}
}

ResfoodServlet

@WebServlet("/resfood.action")
public class ResfoodServlet extends CommonServlet {private void findAllFoods(HttpServletRequest request,HttpServletResponse response) throws IOException {DbHelper db = new DbHelper();JsonModel jsonModel = new JsonModel();List<Resfood> list = null;try {list = db.findMutipl(Resfood.class,"select * from resfood");jsonModel.setCode(1);jsonModel.setData(list);} catch (Exception e) {jsonModel.setCode(0);jsonModel.setMsg(e.getMessage());e.printStackTrace();}super.writeJson(jsonModel,response);}
}

ResorderServlet

@WebServlet("/resorder.action")
public class ResorderServlet extends CommonServlet {private void order (HttpServletRequest request, HttpServletResponse response) throws Exception {JsonModel jsonModel = new JsonModel();try {//判断是否登录HttpSession session = request.getSession();if (session.getAttribute(DataDict.RESUSER)==null){jsonModel.setCode(-1);super.writeJson(jsonModel,response);return;}//获取参数   参数多就写一个类int fid = Integer.parseInt(request.getParameter("fid"));int num = Integer.parseInt(request.getParameter("num"));//验正是否有该商品  能不能购买......//加入购物车  map(fid , 购物车项)Map<Integer, CartItem> cart = null;//线程安全的Mapif (session.getAttribute(DataDict.CART)!=null){cart = (Map<Integer, CartItem>) session.getAttribute(DataDict.CART);}else{cart = new ConcurrentHashMap<>();}//判断是否有fid这个键=====数据库查找String sql = "select * from resfood where fid=?";DbHelper db = new DbHelper();Resfood resfood = db.findSingle(Resfood.class,sql,fid);if(resfood==null){jsonModel.setCode(0);jsonModel.setMsg("无该商品");super.writeJson(jsonModel,response);return;}CartItem cartItem = null;//购物车项if (cart.containsKey(fid)){//有=====原来买过   只用添加数量和小计cartItem=cart.get(fid);cartItem.setNum(cartItem.getNum()+num);}else{cartItem = new CartItem();//原来没有买过cartItem.setResfood(resfood);cartItem.setNum(num);cart.put(fid,cartItem);}cartItem.getSmallCount();//此时就已经设置了小计了cart.put(fid,cartItem);//购买数量<=0   删除这个商品if (cartItem.getNum()<=0){cart.remove(fid);}session.setAttribute(DataDict.CART,cart);//添加成功，回送信息jsonModel.setCode(1);jsonModel.setData(cart);}catch (Exception e){jsonModel.setCode(0);jsonModel.setMsg(e.getMessage());e.printStackTrace();}super.writeJson(jsonModel,response);}private void checkCart(HttpServletRequest request,HttpServletResponse response) throws IOException {HttpSession session  =request.getSession();JsonModel jsonModel = new JsonModel();if(session.getAttribute(DataDict.CART)!=null){jsonModel.setCode(1);jsonModel.setData(session.getAttribute(DataDict.CART));}else{jsonModel.setCode(0);}super.writeJson(jsonModel,response);}private void getCartInfo(HttpServletRequest request,HttpServletResponse response) throws IOException {JsonModel jsonModel = new JsonModel();DbHelper db = new DbHelper();HttpSession session = request.getSession();//以Map<Integer,CartItem> cart形式返回datatry {//检查是否登录if(session.getAttribute(DataDict.RESUSER)==null){jsonModel.setCode(-1);super.writeJson(jsonModel,response);return ;}Map<Integer, CartItem> cart = new ConcurrentHashMap<>();//查询该用户的购物车   保存num resfood smallCount//从数据库查出来放入sessionList<Resorderitem> list = db.findMutipl(Resorderitem.class,"select * from resorderitem");if (list==null || list.isEmpty()){jsonModel.setCode(0);jsonModel.setMsg("购物车为空");return;}for (Resorderitem item:list){CartItem cartItem = new CartItem();cartItem.setNum(item.getNum());//去数据库查出这个fid的信息Resfood resfood = db.findSingle(Resfood.class,"select * from resfood where fid=?",item.getFid());if(resfood!=null){cartItem.setResfood(resfood);}else{//商品在购物车时候停售了。。。。。}cartItem.getSmallCount();cart.put(item.getFid(),cartItem);}session.setAttribute(DataDict.CART,cart);jsonModel.setCode(1);jsonModel.setData(cart);} catch (Exception e) {jsonModel.setCode(0);jsonModel.setMsg(e.getMessage());e.printStackTrace();}super.writeJson(jsonModel,response);}private void clearAll(HttpServletRequest request,HttpServletResponse response) throws IOException {//判断是否登录JsonModel jsonModel = new JsonModel();HttpSession session = request.getSession();if (session.getAttribute(DataDict.RESUSER)==null){jsonModel.setCode(-1);super.writeJson(jsonModel,response);return;}session.removeAttribute(DataDict.CART);jsonModel.setCode(1);jsonModel.setData(session.getAttribute(DataDict.CART));super.writeJson(jsonModel,response);}
}

ResuserServlet

@WebServlet("/resuser.action")
public class ResuserServlet extends CommonServlet {private void login(HttpServletRequest request,HttpServletResponse response) throws IOException {String uname = request.getParameter("uname");String pwd = request.getParameter("pwd");//System.out.println(uname+"   "+pwd);pwd = Encrypt.md5(pwd);//加密String yzm = request.getParameter("yzm");JsonModel jsonModel = new JsonModel();HttpSession session = request.getSession();String validateCode = (String) session.getAttribute("validateCode");if(!validateCode.equals(yzm)){jsonModel.setCode(-1);jsonModel.setMsg("验证码不一致，请验证后登录");super.writeJson(jsonModel,response);return;}DbHelper db = new DbHelper();Resuser resuser = null;try {resuser = db.findSingle(Resuser.class,"select * from resuser where username=? and pwd=?",uname,pwd);if(resuser!=null){jsonModel.setCode(1);resuser.setPwd("");//密码敏感，不要通过网络传输jsonModel.setData(resuser);//登录成功后，在服务器端保存用户信息，方便后序使用=====一个用户对应一个sessionsession.setAttribute("resuser",resuser);}else{jsonModel.setCode(0);jsonModel.setMsg("用户名或密码错误");}} catch (Exception e) {jsonModel.setCode(0);jsonModel.setMsg(e.getMessage());e.printStackTrace();}super.writeJson(jsonModel,response);}private void logout(HttpServletRequest request,HttpServletResponse response) throws IOException {JsonModel jsonModel = new JsonModel();HttpSession session = request.getSession();session.removeAttribute(DataDict.RESUSER);session.removeAttribute(DataDict.CART);jsonModel.setCode(1);super.writeJson(jsonModel,response);}private void checkLogin(HttpServletRequest request,HttpServletResponse response) throws IOException {JsonModel jsonModel = new JsonModel();HttpSession session = request.getSession();Resuser resuser = (Resuser) session.getAttribute("resuser");if(session.getAttribute("resuser")!=null){resuser.setPwd("");//敏感信息jsonModel.setCode(1);jsonModel.setData(resuser);}else{jsonModel.setCode(0);}super.writeJson(jsonModel,response);}private void newyzm(HttpServletRequest request,HttpServletResponse response) throws IOException {Integer number = new Random().nextInt(1000);JsonModel jsonModel = new JsonModel();jsonModel.setCode(1);jsonModel.setData(number);super.writeJson(jsonModel,response);}
}

VerifyCodeServlet

//验证码. 图形码.
@WebServlet("/varifyCode.action")
public class VerifyCodeServlet extends HttpServlet {// 验证码图片的宽度。private int width = 60;// 验证码图片的高度。private int height = 20;// 验证码字符个数private int codeCount = 4;private int x = 0;// 字体高度private int fontHeight;private int codeY;char[] codeSequence = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J','K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W','X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'};//备选验证码组成/*** 初始化验证图片属性*/public void initxuan() throws ServletException {// 从web.xml中获取初始信息// 宽度String strWidth = "80";// 高度String strHeight = "30";// 字符个数String strCodeCount = "4";// 将配置的信息转换成数值try {if (strWidth != null && strWidth.length() != 0) {width = Integer.parseInt(strWidth);}if (strHeight != null && strHeight.length() != 0) {height = Integer.parseInt(strHeight);}if (strCodeCount != null && strCodeCount.length() != 0) {codeCount = Integer.parseInt(strCodeCount);}} catch (NumberFormatException e) {}x = width / (codeCount + 1);fontHeight = height - 2;codeY = height - 4;}@Overridepublic void service(HttpServletRequest req, HttpServletResponse resp)throws ServletException, java.io.IOException {initxuan();// 定义图像bufferBufferedImage buffImg = new BufferedImage(width, height,//缓冲图片对象BufferedImage.TYPE_INT_RGB);Graphics2D g = buffImg.createGraphics();   //  创建一个画布// 创建一个随机数生成器类Random random = new Random();// 将图像填充为白色g.setColor(Color.WHITE);//绘制一个矩形g.fillRect(0, 0, width, height);// 创建字体，字体的大小应该根据图片的高度来定。Font font = new Font("Fixedsys", Font.PLAIN, fontHeight);// 设置字体。g.setFont(font);// 画边框。g.setColor(Color.BLACK);g.drawRect(0, 0, width - 1, height - 1);// 随机产生10条干扰线，使图象中的认证码不易被其它程序探测到。g.setColor(Color.BLACK);for (int i = 0; i < 10; i++) {int x = random.nextInt(width);int y = random.nextInt(height);int xl = random.nextInt(12);int yl = random.nextInt(12);g.drawLine(x, y, x + xl, y + yl);}// randomCode用于保存随机产生的验证码，以便用户登录后进行验证。StringBuffer randomCode = new StringBuffer();int red = 0, green = 0, blue = 0;// 随机产生codeCount数字的验证码。for (int i = 0; i < codeCount; i++) {// 得到随机产生的验证码数字。String strRand = String.valueOf(    codeSequence[random.nextInt(codeSequence.length)]    );// 产生随机的颜色分量来构造颜色值，这样输出的每位数字的颜色值都将不同。red = random.nextInt(255);   //   颜色值 范围 :  0-255green = random.nextInt(255);blue = random.nextInt(255);// 用随机产生的颜色将验证码绘制到图像中。g.setColor(new Color(red, green, blue));g.drawString(strRand, (i + 1) * x, codeY);   //图片上绘制字// 将产生的四个随机数组合在一起。用于存sessionrandomCode.append(strRand);}// **********将四位数字的验证码保存到Session中。HttpSession session = req.getSession();session.setAttribute("validateCode", randomCode.toString());//存随机生成的验证码//允许跨域访问resp.setHeader("Access-Control-Allow-Origin", "*");//手机  服务器默认不可以跨域// 禁止图像缓存。resp.setHeader("Pragma", "no-cache");resp.setHeader("Cache-Control", "no-cache");resp.setDateHeader("Expires", 0);//**************************************设置响应的数据类型：  image/jpeg, 这样浏览器会以图像显示resp.setContentType("image/jpeg");//resp.setContentType("text/html;charset=utf-8");// 将图像输出到Servlet输出流中。//PrintWriter out=resp.getWriter();ServletOutputStream sos = resp.getOutputStream();//因为是图片，所以是字节流ImageIO.write(buffImg, "jpeg", sos);sos.close();}
}

Sverlet案例小萌神服务器端相关推荐

小萌库 - 精品游戏精彩回顾
小萌库( www.xiaomengku.com ) 精品游戏精彩回顾 <海岛大亨5>中文版免安装硬盘版<海岛大亨5>是由美国的PopTop Software / FrogC ...
小萌库 - 2014世界足球杯全程精彩回顾
小萌库( www.xiaomengku.com ) 2014世界足球杯全程精彩回顾 7月14日世界杯决赛德国vs阿根廷北京时间7月14日凌晨3点,2014巴西世界杯决赛,德国通过加时赛1-0击败 ...
小萌谈Art（4）——从零开始学RobotArt
今天呢小萌就来具体学习RobotArt这款离线编程软件啦!希望小萌今天写到的内容可以对大家有所帮助. [软件下载] 要学习RobotArt,首先就要去下载,于是呢小萌就来到了RobotArt的官 ...
java游戏boss是冰龙_那些令人难忘的龙形Boss！这款游戏里的龙居然有点小萌？
在中华传统文化里,龙是祥瑞的象征,也是中华民族的代表.不过在西方文化中,龙的形象跟含义与中华龙相距甚远,这些长翅膀的大蜥蜴往往会成为勇者的背景板.而在各种游戏中,龙也常常作为Boss角色登场.今天小编 ...
android 手电筒开源,1.【小萌伴Android】思量再三，终于鼓起勇气开源～
从12年开始,业余时间陆续也开发了几款App并上架到各大应用市场,可惜没做出啥成绩,也就赚了一些广告费-之前的有几款App现在连源码都找不到了,只留下最后一款<小萌伴>因为放在OsChin ...
小股神助A股股民畅享经济发展红利
小股神助A股股民畅享经济发展红利去年正当全球股市一片哀鸿遍野之时,中国A股市场高歌猛进,于2014年年底顺利攻破四千点指数大关,许多新股民为此也借炒股赚得盆满钵满.而老股民由于受到熊市思维惯性的影响 ...
VS配置永久OpenCV（小萌轻松操作）：超细致
VS配置永久OpenCV(小萌轻松操作):超细致一. 下载安装Visual Studio2022 1.进入:Visual Studio2022的官网,点击Community2022进行下载. 2.双 ...
小萌新开始做题啦！----------相交链表
总算开始了第一次的博客.内心战战兢兢o(╥﹏╥)o 下面来自LeetCode的一道链表题. 题目描述: 编写一个程序,找到两个单链表相交的起始节点. 如下面的两个链表: 在节点 c1 开始相交. 注意 ...
小萌库一周电影大合集
小萌库( www.xiaomengku.com ) 一周电影大合集怪兽大学(Monsters University)-2013美国最新动画片BT下载.torrent.zip好朋友"毛怪& ...
小萌库- 新海诚那些唯美感人的动漫
小萌库( www.xiaomengku.com ) 新海诚那些唯美感人的动漫 [新海诚]秒速5厘米<秒速5厘米>是日本导演新海诚出道后继<星之声>.<云之彼端,约定的地 ...

Sverlet案例小萌神服务器端

1.创建项目，配置tomcat

2.测试项目能否启动

3.创建WEB-INF依赖，导入jar包

4.编写数据库脚本，利用IDEA建表

5.创建包，即创建项目架构

6.写项目

1.commons

2.bean

3.biz

4.web/servlets

Sverlet案例小萌神服务器端相关推荐

最新文章

热门文章