项目知识点记录
1.使用druid连接池
使用properties配置文件：
driverClassName= com.mysql.cj.jdbc.Driver url= jdbc:mysql://localhost:3306/book?useSSL=true&setUnicode=true&charsetEncoding=UTF-8&serverTimezone=GMT%2B8 username= root password= 123456 #初始化链接数量 initialSize=5 #最大链接数 maxActive=10 #最大等待时间 maxWait=3000
工具类：
package com.util;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import javax.sql.DataSource;
import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
public class JDBCUtils {
//定义成员变量
private static DataSource ds = null;
//定义静态代码块
static {
try {
//加载配置文件
Properties pro = new Properties();
pro.load(JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties"));
//获取DataSource
ds = DruidDataSourceFactory.createDataSource(pro);
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
//获取链接
public static Connection getConnection() throws SQLException{
return ds.getConnection();
}
//释放资源
public static void close(Statement stmt,Connection conn){
if (stmt != null){
try {
stmt.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
if (conn != null){
try {
conn.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
}
public static void close(ResultSet rs,Statement stmt,Connection conn){
if (rs != null){
try {
rs.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
close(stmt,conn);
}
//获取链接池方法
public static DataSource getDataSource(){
return ds;
}
}
Dao接口：
dao实现类：
查询：
//定义sql
String sql = "select * from user where username = ? and password = ?";
//执行sql
User user1 = template.queryForObject(sql, new BeanPropertyRowMapper(User.class), user.getUsername(), user.getPassword());
增加：
//定义sql
String sql ="insert into user values(null,?,?)";
//执行sql
int update = template.update(sql, user.getUsername(), user.getPassword());删除：
//定义sql
String sql = "delete from shopping where id = ?";
//执行sql
int update = template.update(sql, id);修改：
//定义sql
String sql ="update books set img = ? , name = ? , price = ? , classly = ? , detail = ? where id = ?";
//执行sql
int update = template.update(sql, books.getImg(), books.getName(), books.getPrice(), books.getClassly(), books.getDetail(), books.getId());
package com.dao;
import com.domain.Admin;
import com.domain.Books;
import com.domain.Shopping;
import com.domain.User;
import com.util.JDBCUtils;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import java.util.concurrent.TimeoutException;
public class DaoImpl implements Dao {
//使用JdbcTemplate
private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
//用户登录
@Override
public User login(User user) {
try {
//定义sql
String sql = "select * from user where username = ? and password = ?";
//执行sql
User user1 = template.queryForObject(sql, new BeanPropertyRowMapper(User.class), user.getUsername(), user.getPassword());
//返回结果
return user1;
} catch (DataAccessException e) {
e.printStackTrace();
return null;
}
}
//用户注册
@Override
public int addUser(User user) {
try {
//定义sql
String sql ="insert into user values(null,?,?)";
//执行sql
int update = template.update(sql, user.getUsername(), user.getPassword());
return update;
} catch (DataAccessException e) {
e.printStackTrace();
return 0;
}
}
//遍历图书
@Override
public List selectBooks(String classly) {
//定义sql
String sql = "select * from books where classly = ?";
//执行sql
List query = template.query(sql, new RowMapper() {
@Override
public Books mapRow(ResultSet resultSet, int i) throws SQLException {
Books b = new Books();
b.setImg(resultSet.getString("img"));
b.setName(resultSet.getString("name"));
b.setPrice(resultSet.getInt("price"));
b.setDetail(resultSet.getString("detail"));
return b;
}
}, classly);
return query;
}
//添加图书
@Override
public int addBook(Books books) {
try {
//定义sql
String sql = "insert into books values(null,?,?,?,?,?)";
//执行sql
int update = template.update(sql, books.getImg(),
books.getName(), books.getPrice(),
books.getClassly(), books.getDetail());
//返回值
return update;
} catch (DataAccessException e) {
e.printStackTrace();
return 0;
}
}
//查询图书详情
@Override
public Books selectDetail(String name) {
//定义sql
String sql ="select * from books where name = ?";
//执行sql
Books query = template.queryForObject(sql, new BeanPropertyRowMapper(Books.class), name);
//返回
return query;
}
//加入购物车
@Override
public int addShopping(Shopping shopping) {
try {
//定义sql
String sql = "insert into shopping values(null,?,?,?,?,?)";
int update = template.update(sql,shopping.getImg(), shopping.getUsername(), shopping.getName(), shopping.getNumber(), shopping.getPrice());
//返回值
return update;
} catch (DataAccessException e) {
e.printStackTrace();
return 0;
}
}
//遍历购物车
@Override
public List selectShopping(String username) {
//定义sql
String sql = "select * from shopping where username = ?";
List query = template.query(sql, new RowMapper() {
@Override
public Shopping mapRow(ResultSet resultSet, int i) throws SQLException {
Shopping shopping = new Shopping();
shopping.setId(resultSet.getInt("id"));
shopping.setImg(resultSet.getString("img"));
shopping.setName(resultSet.getString("name"));
shopping.setNumber(resultSet.getInt("number"));
shopping.setPrice(resultSet.getInt("price"));
return shopping;
}
}, username);
return query;
}
//删除购物车
@Override
public int deleteShopping(int id) {
//定义sql
String sql = "delete from shopping where id = ?";
//执行sql
int update = template.update(sql, id);
//返回执行结果
return update;
}
//清空购物车
@Override
public int deleteS(String username) {
//定义sql
String sql = "delete from shopping where username = ?";
//执行sql
int update = template.update(sql, username);
//返回执行结果
return update;
}
//管理员登录
@Override
public Admin admin(Admin admin) {
try {
//定义sql
String sql = "select * from admin where username = ? and password = ?";
//执行sql
Admin admin1 = template.queryForObject(sql, new BeanPropertyRowMapper(Admin.class), admin.getUsername(), admin.getPassword());
return admin1;
} catch (DataAccessException e) {
e.printStackTrace();
return null;
}
}
//遍历图书
@Override
public List BOOKS_LIST() {
//定义sql
String sql ="select * from books";
//执行sql
List query = template.query(sql, new RowMapper() {
@Override
public Books mapRow(ResultSet resultSet, int i) throws SQLException {
Books b = new Books();
b.setId(resultSet.getInt("id"));
b.setImg(resultSet.getString("img"));
b.setName(resultSet.getString("name"));
b.setPrice(resultSet.getInt("price"));
b.setClassly(resultSet.getString("classly"));
b.setDetail(resultSet.getString("detail"));
return b;
}
});
return query;
}
//删除图书
@Override
public int deleteBooks(String name) {
//定义sql
String sql = "delete from books where name = ?";
//执行sql
int update = template.update(sql, name);
//返回
return update;
}
//修改图书
@Override
public int modifyBook(Books books) {
//定义sql
String sql ="update books set img = ? , name = ? , price = ? , classly = ? , detail = ? where id = ?";
//执行sql
int update = template.update(sql, books.getImg(), books.getName(), books.getPrice(), books.getClassly(), books.getDetail(), books.getId());
//返回
return update;
}
//遍历用户
@Override
public List selectUser() {
//定义sql
String sql ="select * from user";
//执行sql
List query = template.query(sql, new RowMapper() {
@Override
public User mapRow(ResultSet resultSet, int i) throws SQLException {
User u = new User();
u.setId(resultSet.getInt("id"));
u.setUsername(resultSet.getString("username"));
u.setPassword(resultSet.getString("password"));
return u;
}
});
return query;
}
//修改用户
@Override
public int modifyUser(User user) {
//定义sql
String sql = "update user set username = ? , password = ? where id = ?";
//执行sql
int update = template.update(sql, user.getUsername(), user.getPassword(), user.getId());
//返回
return update;
}
@Override
public int deleteUser(int id) {
//定义sql
String sql ="delete from user where id =?";
//执行sql
int update = template.update(sql, id);
return update;
}
}
登录Servlet控制器：
package com.demo;
import com.dao.Dao;
import com.dao.DaoImpl;
import com.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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Map;
@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//设置编码格式
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
//获取数据
Map map = request.getParameterMap();
//封装数据
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//调用dao
Dao dao = new DaoImpl();
User login = dao.login(user);
if (login != null){
HttpSession session = request.getSession();
session.setAttribute("username",user.getUsername());
response.sendRedirect(request.getContextPath()+"/indexServlet?classly=1");
}else {
request.setAttribute("user","账号或密码错误");
request.getRequestDispatcher("login.jsp").forward(request,response);
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
简单的过滤器实现：判断用户是否登录，登录就放行
package com.listener;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
/**
* 登录验证的过滤器
*/
@WebFilter("/*")
public class LoginFilter implements Filter {
public void destroy() {
}
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException {
//强制转换
HttpServletRequest request = (HttpServletRequest) req;
//1.获取资源请求路径
String uri = request.getRequestURI();
//2.判断是否包含登录相关资源路径,要注意排除掉css/图片/js等资源
if (uri.contains("/login.jsp") || uri.contains("/loginServlet")||
uri.contains("/login2.jsp")||uri.contains("/login2Servlet") ||
uri.contains("/css/") || uri.contains("/img/") ||
uri.contains("adlogin.jsp") || uri.contains("/adLoginServlet")){
//包含，用户就是想登录，放行
chain.doFilter(req, resp);
}else {
//不包含，需要验证用户是否登录
//3.从获取session中获取username
Object username = request.getSession().getAttribute("username");
if (username != null){
//登录了，放行
chain.doFilter(req,resp);
}else {
//没有登录，跳转登录页面
request.setAttribute("user","您尚未登录，请登录");
request.getRequestDispatcher("/login.jsp").forward(request,resp);
}
}
//chain.doFilter(req, resp);
}
public void init(FilterConfig config) throws ServletException {
}
}
（2）项目Spring中用的aop事务的写法
