smbms学习笔记（服务器端）
smbms学习笔记（服务器端）
笔记地址：https://github.com/userwusir/study-notes
项目地址：https://github.com/userwusir/smbms
大致的一个流程，从用户的pojo到dao层创建，service层和登录、登出servlet层的书写。
文件目录
pojo层（User）
package com.wll.pojo;
import lombok.*;
import java.util.Calendar;
import java.util.Date;
/**
* @author wulele
* <p>
* 用户表
*/
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@ToString
public class User {
private Integer id;
private String userCode;
private String userName;
private String userPassword;
private Integer gender;
private Date birthday;
private String phone;
private String address;
private Integer userRole;
private Integer createdBy;
private Date creationDate;
private Integer modifyBy;
private Date modifyDate;
private Integer age;
private String userRoleName;
public void setUserRoleName(String userRoleName) {
this.userRoleName = userRoleName;
}
public Integer getAge() {
Calendar calendar = Calendar.getInstance();
Calendar date = Calendar.getInstance();
date.setTime(this.birthday);
return calendar.get(Calendar.YEAR) - date.get(Calendar.YEAR);
}
}
公共类
package com.wll.dao;
import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;
/**
* @author wulele
* <p>
* 操作数据库公共类
*/
public class BaseDao {
private static String driver;
private static String url;
private static String username;
private static String password;
static {
Properties properties = new Properties();
//通过类加载器读取资源
InputStream rs = BaseDao.class.getClassLoader().getResourceAsStream("db.properties");
try {
properties.load(rs);
} catch (IOException e) {
e.printStackTrace();
}
driver = properties.getProperty("driver");
url = properties.getProperty("url");
username = properties.getProperty("username");
password = properties.getProperty("password");
}
public static Connection getConnection() throws ClassNotFoundException, SQLException {
Connection connection = null;
//反射获取对象
Class.forName(driver);
connection = DriverManager.getConnection(url, username, password);
return connection;
}
/**
* 查询公共类
*/
public static PreparedStatement execute(Connection connection, String sql, Object[] params, PreparedStatement preparedStatement, ResultSet resultSet) throws SQLException {
preparedStatement = connection.prepareStatement(sql);
for (int i = 0; i < params.length; i++) {
//preparedStatement占位符从1开始
preparedStatement.setObject(i + 1, params[i]);
}
return preparedStatement;
}
/**
* 增删改共类
*/
public static PreparedStatement executeUpdate(Connection connection, String sql, Object[] params, PreparedStatement preparedStatement) throws SQLException {
preparedStatement = connection.prepareStatement(sql);
for (int i = 0; i < params.length; i++) {
//preparedStatement占位符从1开始
preparedStatement.setObject(i + 1, params[i]);
}
return preparedStatement;
}
/**
* 关闭资源
*/
public static boolean closeResources(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet) {
boolean flag = true;
if (resultSet != null) {
try {
resultSet.close();
//GC回收
resultSet = null;
} catch (SQLException throwables) {
throwables.printStackTrace();
flag = false;
}
}
if(preparedStatement!=null){
try {
preparedStatement.close();
preparedStatement = null;
} catch (SQLException throwables) {
throwables.printStackTrace();
flag = false;
}
}
if(connection != null){
try {
connection.close();
connection = null;
} catch (SQLException throwables) {
throwables.printStackTrace();
flag = false;
}
}
return flag;
}
}
持久层（UserDao、UserDaoImpl）
package com.wll.dao.user;
import com.wll.pojo.User;
import java.sql.Connection;
import java.sql.SQLException;
/**
* @author wulele
*/
public interface UserDao {
/**
* get user info.
* @param connection
* @param userCode
* @return User
* @throws SQLException getUserInfo
*/
public User getUserInfo(Connection connection, String userCode) throws SQLException;
}
package com.wll.dao.user;
import com.wll.dao.BaseDao;
import com.wll.pojo.User;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
/**
* @author wulele
*/
public class UserDaoImpl implements UserDao {
@Override
public User getUserInfo(Connection connection, String userCode) throws SQLException {
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
User user = null;
if (connection != null) {
String sql = "select * from smbms_user where userCode = ?";
Object[] params = {userCode};
preparedStatement = BaseDao.execute(connection, sql, params, preparedStatement, resultSet);
resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
user = new User();
user.setId(resultSet.getInt("id"));
user.setUserCode(resultSet.getString("userCode"));
user.setUserName(resultSet.getString("userName"));
user.setUserPassword(resultSet.getString("userPassword"));
user.setGender(resultSet.getInt("gender"));
user.setBirthday(resultSet.getDate("birthday"));
user.setPhone(resultSet.getString("phone"));
user.setAddress(resultSet.getString("address"));
user.setUserRole(resultSet.getInt("userRole"));
user.setCreatedBy(resultSet.getInt("createdBy"));
user.setCreationDate(resultSet.getTimestamp("creationDate"));
user.setModifyBy(resultSet.getInt("modifyBy"));
user.setModifyDate(resultSet.getTimestamp("modifyDate"));
}
BaseDao.closeResources(connection, preparedStatement, resultSet);
}
return user;
}
}
Service层（UserService、UserServiceImpl）
package com.wll.service.user;
import com.wll.pojo.User;
/**
* @author wulele
*/
public interface UserService {
/**
* method for user login.
* @param userCode
* @param password
* @return
*/
public User login(String userCode,String password);
}
package com.wll.service.user;
import com.wll.dao.BaseDao;
import com.wll.dao.user.UserDao;
import com.wll.dao.user.UserDaoImpl;
import com.wll.pojo.User;
import java.sql.Connection;
import java.sql.SQLException;
/**
* @author wulele
*/
public class UserServiceImpl implements UserService{
/** 业务层调用Dao层 */
private UserDao userDao;
public UserServiceImpl(){
userDao = new UserDaoImpl();
}
@Override
public User login(String userCode, String password) {
Connection connection = null;
User userInfo = null;
try {
connection = BaseDao.getConnection();
userInfo = userDao.getUserInfo(connection, userCode);
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
} finally {
BaseDao.closeResources(connection,null,null);
}
if (userCode.equals(userInfo.getUserCode()) && password.equals(userInfo.getUserPassword())){
return userInfo;
}else {
return null;
}
}
}
Servlet层（LoginServlet 、LogutServlet）
package com.wll.servlet.user;
import com.wll.pojo.User;
import com.wll.service.user.UserService;
import com.wll.service.user.UserServiceImpl;
import com.wll.util.Constant;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @author wulele
*/
public class LoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String userCode = req.getParameter("userCode");
String userPassword = req.getParameter("userPassword");
UserService userService = new UserServiceImpl();
User user = userService.login(userCode, userPassword);
if(user!=null){
//登录保存session
req.getSession().setAttribute(Constant.USER_SESSION,user);
//重定向地址发生变化，项目地址为 smbms
resp.sendRedirect("/smbms/jsp/frame.jsp");
//resp.sendRedirect(req.getContextPath()+"/jsp/frame.jsp");
}else {
//错误信息只在一次请求中有效
req.setAttribute("error","账号或密码有误");
//请求转发，地址不发生变化，request对象未销毁，error信息保留
req.getRequestDispatcher("/login.jsp").forward(req,resp);
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req, resp);
}
}
package com.wll.servlet.user;
import com.wll.util.Constant;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @author wulele
*/
public class LogoutServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.getSession().removeAttribute(Constant.USER_SESSION);
resp.sendRedirect(req.getContextPath()+"/login.jsp");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req, resp);
}
}
字符过滤器、登出过滤器
package com.wll.filter;
import javax.servlet.*;
import java.io.IOException;
/**
* @author wulele
*/
public class CharacterEncoding implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
chain.doFilter(request,response);
}
@Override
public void destroy() {
}
}
package com.wll.filter;
import com.wll.pojo.User;
import com.wll.util.Constant;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @author wulele
*/
public class SysFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse resp = (HttpServletResponse) response;
User user = (User) req.getSession().getAttribute(Constant.USER_SESSION);
if(user ==null){
resp.sendRedirect("/smbms/jsp/error.jsp");
}else {
chain.doFilter(request,response);
}
}
@Override
public void destroy() {
}
}
<!--CharacterEncoding filter-->
<filter>
<filter-name>CharacterEncoding</filter-name>
<filter-class>com.wll.filter.CharacterEncoding</filter-class>
</filter>
<filter-mapping>
<filter-name>CharacterEncoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!--login filter-->
<filter>
<filter-name>SysFilter</filter-name>
<filter-class>com.wll.filter.SysFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>SysFilter</filter-name>
<url-pattern>/jsp/frame.jsp</url-pattern>
</filter-mapping>
