* 開發步驟
?? ?1. 創建項目，導入html頁面，配置文件，jar包
?? ?2. 創建數據庫環境
?? ??? ?CREATE DATABASE test;
?? ??? ?USE test;

CREATE TABLE `USER` (`id` int(11) NOT NULL AUTO_INCREMENT,`username` varchar(255) DEFAULT NULL,`password` varchar(255) DEFAULT NULL,PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;insert into user values(null,'superbaby','123456'); package com.learn.domain;/*** 用戶的實體類*/ public class User {private int id;private String username;private String password;private String gender;public void setHehe(String gender){this.gender = gender;}public String getHehe(){return gender;}public int getId() {return id;}public void setId(int id) {this.id = id;}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;}@Overridepublic String toString() {return "User{" +"id=" + id +", username='" + username + '\'' +", password='" + password + '\'' +", gender='" + gender + '\'' +'}';} } package com.learn.util;import com.alibaba.druid.pool.DruidDataSourceFactory;import javax.sql.DataSource; import javax.xml.crypto.Data; import java.io.IOException; import java.io.InputStream; import java.sql.Connection; import java.sql.SQLException; import java.util.Properties;/*** JDBC工具類 使用Durid連接池*/ public class JDBCUtils {private static DataSource ds ;static {try {//1.加載配置文件Properties pro = new Properties();//使用ClassLoader加載配置文件，獲取字節輸入流InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties");pro.load(is);//2.初始化連接池對象ds = DruidDataSourceFactory.createDataSource(pro);} catch (IOException e) {e.printStackTrace();} catch (Exception e) {e.printStackTrace();}}/*** 獲取連接池對象*/public static DataSource getDataSource(){return ds;}/*** 獲取連接Connection對象*/public static Connection getConnection() throws SQLException {return ds.getConnection();} } package com.learn.dao;import com.learn.domain.User; import com.learn.util.JDBCUtils; import org.springframework.dao.DataAccessException; import org.springframework.jdbc.core.BeanPropertyRowMapper; import org.springframework.jdbc.core.JdbcTemplate;/*** 操作數據庫中User表的類*/ public class UserDao {//聲明JDBCTemplate對象共用private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());/*** 登錄方法* @param loginUser 只有用戶名和密碼* @return user包含用戶全部數據,沒有查詢到，返回null*/public User login(User loginUser){try {//1.編寫sqlString sql = "select * from user where username = ? and password = ?";//2.調用query方法User user = template.queryForObject(sql,new BeanPropertyRowMapper<User>(User.class),loginUser.getUsername(), loginUser.getPassword());return user;} catch (DataAccessException e) {e.printStackTrace();//記錄日志return null;}} } package com.learn.test;import com.learn.dao.UserDao; import com.learn.domain.User; import org.junit.Test;public class UserDaoTest {@Testpublic void testLogin(){User loginuser = new User();loginuser.setUsername("superbaby");loginuser.setPassword("123111");UserDao dao = new UserDao();User user = dao.login(loginuser);System.out.println(user);} } package com.learn.web.servlet;import com.learn.dao.UserDao; import com.learn.domain.User; import org.apache.commons.beanutils.BeanUtils;import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.lang.reflect.InvocationTargetException; import java.util.Map;@WebServlet("/loginServlet") public class LoginServlet extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {//1.設置編碼req.setCharacterEncoding("utf-8");/* //2.獲取請求參數String username = req.getParameter("username");String password = req.getParameter("password");//3.封裝user對象User loginUser = new User();loginUser.setUsername(username);loginUser.setPassword(password);*///2.獲取所有請求參數Map<String, String[]> map = req.getParameterMap();//3.創建User對象User loginUser = new User();//3.2使用BeanUtils封裝try {BeanUtils.populate(loginUser,map);} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}//4.調用UserDao的login方法UserDao dao = new UserDao();User user = dao.login(loginUser);//5.判斷userif(user == null){//登錄失敗req.getRequestDispatcher("/failServlet").forward(req,resp);}else{//登錄成功//存儲數據req.setAttribute("user",user);//轉發req.getRequestDispatcher("/successServlet").forward(req,resp);}}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {this.doGet(req,resp);} } package com.learn.web.servlet;import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException;@WebServlet("/failServlet") public class FailServlet extends HttpServlet {protected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//給頁面寫一句話//設置編碼response.setContentType("text/html;charset=utf-8");//輸出response.getWriter().write("登錄失敗，用戶名或密碼錯誤");}protected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {this.doPost(request,response);} } package com.learn.web.servlet;import com.learn.domain.User;import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException;@WebServlet("/successServlet") public class SuccessServlet extends HttpServlet {protected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//獲取request域中共享的user對象User user = (User) request.getAttribute("user");if(user != null){//給頁面寫一句話//設置編碼response.setContentType("text/html;charset=utf-8");//輸出response.getWriter().write("登錄成功！"+user.getUsername()+",歡迎您");}}protected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {this.doPost(request,response);} } package com.learn.test;import com.learn.domain.User; import org.apache.commons.beanutils.BeanUtils; import org.junit.Test;import java.lang.reflect.InvocationTargetException;public class BeanUtilsTest {@Testpublic void test(){User user = new User();try {BeanUtils.setProperty(user,"hehe","male");System.out.println(user);String gender = BeanUtils.getProperty(user, "hehe");System.out.println(gender);} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();} catch (NoSuchMethodException e) {e.printStackTrace();}} } driverClassName=com.mysql.jdbc.Driver url=jdbc:mysql:///test username=root password=123456 initialSize=5 maxActive=10 maxWait=3000 <!DOCTYPE html> <html lang="en"> <head><meta charset="UTF-8"><title>Title</title> </head> <body><form action="/day14_test/loginServlet" method="post">用戶名:<input type="text" name="username"> <br>密碼:<input type="password" name="password"><br><input type="submit" value="登錄"></form> </body> </html>

8. login.html中form表單的action路徑的寫法
?? ?* 虛擬目錄+Servlet的資源路徑

9. BeanUtils工具類，簡化數據封裝
?? ?* 用于封裝JavaBean的
?? ?1. JavaBean：標準的Java類
?? ??? ?1. 要求：
?? ??? ??? ?1. 類必須被public修飾
?? ??? ??? ?2. 必須提供空參的構造器
?? ??? ??? ?3. 成員變量必須使用private修飾
?? ??? ??? ?4. 提供公共setter和getter方法
?? ??? ?2. 功能：封裝數據
2. 概念：
?? ?成員變量：
?? ?屬性：setter和getter方法截取后的產物
?? ??? ?例如：getUsername() --> Username--> username
?

3. 方法：
?? ?1. setProperty()
?? ?2. getProperty()
?? ?3. populate(Object obj , Map map):將map集合的鍵值對信息，封裝到對應的JavaBean對象中
?

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