原生的Web项目(不用框架)

人的命运呐，就是不能预料……

导入jar包，贴好代码（Java命名存在不规范）

建表（sql建表语句.txt）

 1 CREATE TABLE `userinfo` (
 2   `id` int(11) NOT NULL AUTO_INCREMENT,
 3   `username` varchar(45) DEFAULT NULL,
 4   `password` varchar(45) DEFAULT NULL,
 5   PRIMARY KEY (`id`)
 6 )
 7 
 8 CREATE TABLE `useraddr` (
 9   `id` int(11) NOT NULL AUTO_INCREMENT,
10   `country` varchar(45) DEFAULT NULL,
11   `city` varchar(45) DEFAULT NULL,
12   `userid` varchar(45) DEFAULT NULL,
13   PRIMARY KEY (`id`)
14 )

userServlet.java

 1 package com.roadArchitectWeb.control;
 2 
 3 import java.io.IOException;
 4 import java.sql.Connection;
 5 import java.sql.SQLException;
 6 
 7 import javax.servlet.RequestDispatcher;
 8 import javax.servlet.ServletException;
 9 import javax.servlet.http.HttpServlet;
10 import javax.servlet.http.HttpServletRequest;
11 import javax.servlet.http.HttpServletResponse;
12 
13 import com.roadArchitectWeb.Service.userService;
14 import com.roadArchitectWeb.entity.UserInfo;
15 import com.roadArchitectWeb.util.ConnectionFactory;
16 
17 public class userServlet extends HttpServlet {
18     userService userService = new userService();
19 
20     @Override
21     protected void doPost(HttpServletRequest req, HttpServletResponse resp)
22             throws ServletException, IOException {
23         String userName = req.getParameter("userName");
24         String passWord = req.getParameter("passWord");
25         UserInfo user = new UserInfo();
26         user.setUsername(userName);
27         user.setPassword(passWord);
28 
29         ConnectionFactory connectionFactory = ConnectionFactory.getInstance();
30         Connection conn = connectionFactory.getConnection();
31         try {
32             if (userService.checkUser(conn, user)) {
33                 System.out.println("userServlet.doPost()" + "登陆成功");
34                 RequestDispatcher rd = req
35                         .getRequestDispatcher("/login/welcome.jsp");
36                 req.setAttribute("userName", userName);
37                 req.setAttribute("passWord", passWord);
38                 req.setAttribute("login", "1");
39                 rd.forward(req, resp);
40             } else {
41                 System.out.println("userServlet.doPost()" + "登陆失败");
42                 RequestDispatcher rd = req
43                         .getRequestDispatcher("/login/welcome.jsp");
44                 req.setAttribute("userName", userName);
45                 req.setAttribute("passWord", passWord);
46                 rd.forward(req, resp);
47             }
48         } catch (SQLException e) {
49             e.printStackTrace();
50         }
51     }
52 
53 }

userService.java

 1 package com.roadArchitectWeb.Service;
 2 
 3 import java.sql.Connection;
 4 import java.sql.SQLException;
 5 
 6 import com.roadArchitectWeb.dao.UserDao;
 7 import com.roadArchitectWeb.dao.UserDaoImpl;
 8 import com.roadArchitectWeb.entity.UserInfo;
 9 
10 public class userService {
11     UserDao userDao = new UserDaoImpl();
12 
13     public boolean checkUser(Connection conn, UserInfo userInfo)
14             throws SQLException {
15         Boolean status = false;
16         try {
17             conn.setAutoCommit(false);
18             status = userDao.queryUser(conn, userInfo);
19             conn.commit();
20         } catch (Exception e) {
21             e.printStackTrace();
22             conn.rollback();
23             try {
24                 conn.setAutoCommit(true);
25             } catch (SQLException e3) {
26                 e3.printStackTrace();
27             }
28         }
29         return status;
30     }
31 
32 }

UserDao.java

 1 package com.roadArchitectWeb.dao;
 2 
 3 import java.sql.Connection;
 4 import java.sql.SQLException;
 5 
 6 import com.roadArchitectWeb.entity.UserAddr;
 7 import com.roadArchitectWeb.entity.UserInfo;
 8 
 9 public interface UserDao {
10     public void save(Connection conn, UserAddr userAddr) throws SQLException;
11 
12     public void update(Connection conn, UserAddr userAddr) throws SQLException;
13 
14     public void delete(Connection conn, long id) throws SQLException;
15 
16     public UserAddr singalSelect(Connection conn, long id) throws SQLException;
17 
18     public boolean queryUser(Connection conn, UserInfo userInfo)
19             throws SQLException;
20 }

UserDaoImpl.java

 1 package com.roadArchitectWeb.dao;
 2 
 3 import java.sql.Connection;
 4 import java.sql.PreparedStatement;
 5 import java.sql.ResultSet;
 6 import java.sql.SQLException;
 7 
 8 import com.roadArchitectWeb.entity.UserAddr;
 9 import com.roadArchitectWeb.entity.UserInfo;
10 
11 public class UserDaoImpl implements UserDao {
12 
13     @Override
14     public void save(Connection conn, UserAddr userAddr) throws SQLException {
15         String saveSql = "insert into useraddr(country,city,userid) values(?,?,?)";
16         PreparedStatement ps = conn.prepareCall(saveSql);
17         ps.setString(1, userAddr.getCountry());
18         ps.setString(2, userAddr.getCity());
19         ps.setString(3, userAddr.getUserid());
20         ps.execute();
21     }
22 
23     @Override
24     public void update(Connection conn, UserAddr userAddr) throws SQLException {
25         String updateSql = "update useraddr set country=?,city=?,userid=? where id=?";
26         PreparedStatement ps = conn.prepareStatement(updateSql);
27         ps.setString(1, userAddr.getCountry());
28         ps.setString(2, userAddr.getCity());
29         ps.setString(3, userAddr.getUserid());
30         ps.setLong(4, userAddr.getId());
31         ps.execute();
32     }
33 
34     @Override
35     public void delete(Connection conn, long id) throws SQLException {
36         String deleteSql = "delete from useraddr where id = ?";
37         PreparedStatement ps = conn.prepareStatement(deleteSql);
38         ps.setLong(1, id);
39         ps.execute();
40     }
41 
42     @Override
43     public UserAddr singalSelect(Connection conn, long id) throws SQLException {
44         String selectSql = "select * from useraddr where id = ?";
45         PreparedStatement ps = conn.prepareStatement(selectSql);
46         ps.setLong(1, id);
47         ResultSet rs = ps.executeQuery();
48         UserAddr userAddr = new UserAddr();
49         while (rs.next()) {
50             userAddr.setId(id);
51             userAddr.setCountry(rs.getString("country"));
52             userAddr.setCity(rs.getString("city"));
53             userAddr.setUserid(rs.getString("userid"));
54         }
55         return userAddr;
56     }
57 
58     public boolean queryUser(Connection conn, UserInfo userInfo)
59             throws SQLException {
60         String sql = "select * from userinfo where username=? and password=?";
61         PreparedStatement st = conn.prepareStatement(sql);
62         st.setString(1, userInfo.getUsername());
63         st.setString(2, userInfo.getPassword());
64         ResultSet rst = st.executeQuery();
65         if (rst.next())
66             return true;
67         else {
68             return false;
69         }
70     }
71 }

ConnectionFactory.java

 1 package com.roadArchitectWeb.util;
 2 
 3 import java.io.InputStream;
 4 import java.sql.Connection;
 5 import java.sql.DriverManager;
 6 import java.util.Properties;
 7 
 8 public class ConnectionFactory {
 9 
10     private static Connection conn = null;
11     private static String driver;
12     private static String dburl;
13     private static String user;
14     private static String password;
15 
16     private static ConnectionFactory connectionFactory = new ConnectionFactory();
17 
18     static {
19         Properties prop = new Properties();
20         try {
21             InputStream in = ConnectionFactory.class.getClassLoader()
22                     .getResourceAsStream("dbconfig.properties");
23             prop.load(in);
24         } catch (Exception e) {
25             System.out.println("properties file read error");
26         }
27 
28         driver = prop.getProperty("driver");
29         dburl = prop.getProperty("dbUrl");
30         user = prop.getProperty("user");
31         password = prop.getProperty("password");
32     }
33 
34     private ConnectionFactory() {
35 
36     }
37 
38     public Connection getConnection() {
39         try {
40             Class.forName(driver);
41             conn = DriverManager.getConnection(dburl, user, password);
42         } catch (Exception e) {
43             e.printStackTrace();
44         }
45         return conn;
46     }
47 
48     public static ConnectionFactory getInstance() {
49         return connectionFactory;
50     }
51 }

IdEntity.java

 1 package com.roadArchitectWeb.entity;
 2 
 3 public abstract class IdEntity {
 4     protected long id;
 5 
 6     public long getId() {
 7         return id;
 8     }
 9 
10     public void setId(long id) {
11         this.id = id;
12     }
13 
14     @Override
15     public String toString() {
16         return "IdEntity [id=" + id + ", getId()=" + getId() + ", getClass()="
17                 + getClass() + ", hashCode()=" + hashCode() + ", toString()="
18                 + super.toString() + "]";
19     }
20 
21 }

UserAddr.java

 1 package com.roadArchitectWeb.entity;
 2 
 3 public class UserAddr extends IdEntity {
 4     private String country;
 5     private String city;
 6     private String userid;
 7 
 8     public String getCountry() {
 9         return country;
10     }
11 
12     public void setCountry(String country) {
13         this.country = country;
14     }
15 
16     public String getCity() {
17         return city;
18     }
19 
20     public void setCity(String city) {
21         this.city = city;
22     }
23 
24     public String getUserid() {
25         return userid;
26     }
27 
28     public void setUserid(String userid) {
29         this.userid = userid;
30     }
31 
32     @Override
33     public String toString() {
34         return "UserAddr [country=" + country + ", city=" + city + ", userid="
35                 + userid + ", id=" + id + ", getCountry()=" + getCountry()
36                 + ", getCity()=" + getCity() + ", getUserid()=" + getUserid()
37                 + ", getId()=" + getId() + ", toString()=" + super.toString()
38                 + ", getClass()=" + getClass() + ", hashCode()=" + hashCode()
39                 + "]";
40     }
41 
42 }

UserInfo.java

 1 package com.roadArchitectWeb.entity;
 2 
 3 public class UserInfo extends IdEntity {
 4     private String username;
 5     private String password;
 6     private String email;
 7 
 8     public String getUsername() {
 9         return username;
10     }
11 
12     public void setUsername(String username) {
13         this.username = username;
14     }
15 
16     public String getPassword() {
17         return password;
18     }
19 
20     public void setPassword(String password) {
21         this.password = password;
22     }
23 
24     public String getEmail() {
25         return email;
26     }
27 
28     public void setEmail(String email) {
29         this.email = email;
30     }
31 
32     @Override
33     public String toString() {
34         return "UserInfo [username=" + username + ", password=" + password
35                 + ", email=" + email + ", id=" + id + ", getUsername()="
36                 + getUsername() + ", getPassword()=" + getPassword()
37                 + ", getEmail()=" + getEmail() + ", getId()=" + getId()
38                 + ", getClass()=" + getClass() + ", hashCode()=" + hashCode()
39                 + ", toString()=" + super.toString() + "]";
40     }
41 
42 }

测试方法（3个）：

createjson.java

 1 package com.roadArchitectWeb.Test;
 2 
 3 import com.google.gson.JsonArray;
 4 import com.google.gson.JsonObject;
 5 
 6 public class createjson {
 7     public static void main(String[] args) {
 8         JsonObject jsonObject = new JsonObject();
 9         jsonObject.addProperty("start", "This is start");
10 
11         JsonArray jsonArray = new JsonArray();
12         JsonObject jsonObject1 = new JsonObject();
13         jsonObject1.addProperty("1", 1);
14         jsonObject1.addProperty("2", 2);
15         JsonObject jsonObject2 = new JsonObject();
16         jsonObject2.addProperty("3", "3");
17         jsonObject2.addProperty("4", "4");
18         JsonObject jsonObject3 = new JsonObject();
19         jsonObject3.addProperty("5", true);
20         jsonObject3.addProperty("6", false);
21         jsonArray.add(jsonObject1);
22         jsonArray.add(jsonObject2);
23         jsonArray.add(jsonObject3);
24 
25         jsonObject.add("middle", jsonArray);
26         jsonObject.addProperty("end", "This is end");
27 
28         System.out.println("createjson.main():" + jsonObject.toString());
29     }
30 }

测试结果：

JsonRead.java

 1 package com.roadArchitectWeb.Test;
 2 
 3 import java.io.FileNotFoundException;
 4 import java.io.FileReader;
 5 
 6 import com.google.gson.JsonArray;
 7 import com.google.gson.JsonObject;
 8 import com.google.gson.JsonParser;
 9 import com.google.gson.stream.JsonReader;
10 
11 public class JsonRead {
12     public static void main(String[] args) {
13         JsonParser jsonParser = new JsonParser();
14         JsonReader jsonReader=null;
15         try {
16             jsonReader = new JsonReader(new FileReader("src/test.json"));//这里为什么不能用相对路径
17         } catch (FileNotFoundException e) {
18             e.printStackTrace();
19         }
20         JsonObject jsonObject = (JsonObject) jsonParser.parse(jsonReader);
21         
22         String start = jsonObject.get("start").getAsString();
23         
24         JsonArray middleObject = jsonObject.get("middle").getAsJsonArray();
25         
26         int middle1 = ((JsonObject) middleObject.get(0)).get("1").getAsInt();
27         String middle2a = ((JsonObject) middleObject.get(0)).get("2").getAsString();
28         int middle3 = ((JsonObject) middleObject.get(1)).get("3").getAsInt();
29         String middle4a = ((JsonObject) middleObject.get(1)).get("4").getAsString();
30         int middle5 = ((JsonObject) middleObject.get(2)).get("5").getAsInt();
31         String middle6a = ((JsonObject) middleObject.get(2)).get("6").getAsString();
32         
33         Boolean end = jsonObject.get("end").getAsBoolean();
34         System.out.println("JsonRead.main():"+start);
35         System.out.println("JsonRead.main():"+middle1+" "+middle2a+" "+middle3+" "+middle4a+" "+middle5+" "+middle6a);
36         System.out.println("JsonRead.main():"+end);
37     }
38     
39     
40 }

测试结果：

UserDaoTest.java

 1 package com.roadArchitectWeb.Test;
 2 
 3 import java.sql.Connection;
 4 import java.sql.SQLException;
 5 
 6 import com.roadArchitectWeb.dao.UserDao;
 7 import com.roadArchitectWeb.dao.UserDaoImpl;
 8 import com.roadArchitectWeb.entity.UserAddr;
 9 import com.roadArchitectWeb.util.ConnectionFactory;
10 
11 public class UserDaoTest {
12     public  static void main(String[] args) throws SQLException{
13         ConnectionFactory connectionFactory = ConnectionFactory.getInstance();
14         Connection conn = connectionFactory.getConnection();
15     
16         UserDao userDao = new UserDaoImpl();
17         UserAddr userAddr = new UserAddr();
18 //        userAddr.setCountry("China");
19 //        userAddr.setCity("hangzhou");
20 //        userAddr.setUserid("10");
21 //        userDao.save(conn,userAddr);
22         
23 //        userAddr.setId(5);
24 //        userAddr.setCity("nanjing");
25 //        userAddr.setCountry("USA");
26 //        userAddr.setUserid("11");
27 //        userDao.update(conn, userAddr);
28         
29 //        userDao.delete(conn, 4);
30         
31 //        userAddr = userDao.singalSelect(conn,5);
32     }
33 }

测试结果（useraddr表）：

等

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>login.jsp</title>
 8 </head>
 9 <body>
10 
11     <form action="<%=request.getContextPath()%>/userServlet" method="post">
12         用户名:<input type="text" name="userName"></input>
13         密码:<input type="password" name="passWord"></input>
14         <input type="submit" value="submit"></input>
15     </form>
16 
17 </body>
18 </html>

welcome.jsp

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title></title>
 8 </head>
 9 <body>
10     <%
11         String userName = request.getAttribute("userName").toString();
12         if (null != request.getAttribute("login") && !"".equals(request.getAttribute("login").toString()))
13             out.println(userName + " success,欢迎来到登陆界面");
14         else
15             out.println(userName + " fail,请回到登陆界面");
16     %>
17 </body>
18 </html>

web.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
 3   <display-name>roadArchitectWeb</display-name>
 4   <welcome-file-list>
 5     <welcome-file>index.html</welcome-file>
 6     <welcome-file>index.htm</welcome-file>
 7     <welcome-file>index.jsp</welcome-file>
 8     <welcome-file>default.html</welcome-file>
 9     <welcome-file>default.htm</welcome-file>
10     <welcome-file>default.jsp</welcome-file>
11   </welcome-file-list>
12  
13    <servlet>
14       <servlet-name>userServlet</servlet-name>
15       <servlet-class>com.roadArchitectWeb.control.userServlet</servlet-class>
16       <init-param>
17           <param-name>firstName</param-name>
18           <param-value>majintao</param-value>
19       </init-param>
20       <init-param>
21           <param-name>firstPassword</param-name>
22           <param-value>majintaop</param-value>
23       </init-param>
24   </servlet>
25   <servlet-mapping>
26       <servlet-name>userServlet</servlet-name>
27       <url-pattern>/userServlet</url-pattern>
28   </servlet-mapping>
29   
30 </web-app>

dbconfig.properties

driver=com.mysql.jdbc.Driver
dbUrl=jdbc:mysql://localhost:3306/chenyu_db
user=root
password=

test.json

{
	"start":"this is start",
	"middle":
		[{"1":1,"2":"2a"},
		 {"3":3,"4":"4a"},
		 {"5":5,"6":"6a"}],
	"end":true
}

3个jar包：gson-2.2.4-sources.jar、gson-2.2.4.jar、mysql-connector-java-5.1.38-bin.jar

在useraddr中插入数据：

发布工程，访问http://localhost:9080/roadArchitectWeb/login/login.jsp

提交，登陆成功。

代码就是详细理解的过程了。

参考原文：http://blog.csdn.net/jintao_ma/article/details/51051281

击石乃有火，不击元无烟！！

相关阅读:
flask（十）使用alembic，进行数据库结构管理，升级，加表，加项
 Python sqlalchemy使用
 flask+script命令行交互工具
 flask+APScheduler 任务调度，计划任务，定时任务
 DBA日常工作职责
 Oracle 的 VKTM 进程
 linux
UF2.0、O4、UFT、TA众明星背后的秘密
 ORA-01502: 索引或这类索引的分区处于不可用状态
 关于Optimizer_index_cost_adj参数的设置
原文地址：https://www.cnblogs.com/rain2020/p/6736616.html