MVC模式实现用户信息列表展示案例

用户信息列表展示案例

1.需求:实现用户信息查询

效果：

1.设计：Servlet+JSP+My![在这里插入图片描述](https://img-blog.csdnimg.cn/2020121020485663.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTI4OTM3NA==,size_16,color_FFFFFF,t_70#pic_center)
SQL+JDBCTempleat+Duird+BeanUtilS+tomcat
2.设计数据库：
  create database day101; -- 创建数据库
		use day101; 			   -- 使用数据库
		create table user(   -- 创建表
			id int primary key auto_increment,
			name varchar(20) not null,
			gender varchar(5),
			age int,
			address varchar(32),
			qq	varchar(20),
			email varchar(50)
		);  
3.将相应的jar包导入



 
    

​

4.导入jdbc工具类并配置properties
public class JDBCUtils {

    private static DataSource ds ;

    static {

        try {
            //1.加载配置文件
            Properties pro = new Properties();
            //使用ClassLoader加载配置文件，获取字节输入流
            InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties");
            pro.load(is);

            //2.初始化连接池对象
            ds = DruidDataSourceFactory.createDataSource(pro);

        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 获取连接池对象
     */
    public static DataSource getDataSource(){
        return ds;
    }


    /**
     * 获取连接Connection对象
     */
    public static Connection getConnection() throws SQLException {
        return  ds.getConnection();
    }
}

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql:///day101
username=root
password=root
# 初始化连接数量
initialSize=5
# 最大连接数
maxActive=10
# 最大等待时间
maxWait=3000

4.代码设计
1 创建user类
 public class User {
    private  int id ;
    private  String name;
    private  String gender;
    private  int age;
    private String address;
    private String qq;
    private  String email;

    public User() {
    }

    public User(int id, String name, String gender, int age, String address, String qq, String email) {
        this.id = id;
        this.name = name;
        this.gender = gender;
        this.age = age;
        this.address = address;
        this.qq = qq;
        this.email = email;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", gender='" + gender + '\'' +
                ", age=" + age +
                ", address='" + address + '\'' +
                ", qq='" + qq + '\'' +
                ", email='" + email + '\'' +
                '}';
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getQq() {
        return qq;
    }

    public void setQq(String qq) {
        this.qq = qq;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }
}
2 创建userdao接口
    public interface UserDao {
    public List<User> findAll();
}
3创建userdao接口的实现类
    public class UserDaoImpl implements UserDao {
    private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
    @Override
    public List<User> findAll() {
        String sql = "select * from user";
        List<User> users = template.query(sql, new BeanPropertyRowMapper<User>(User.class));
        return users;

    }
}
4创建user的服务层userservice接口
    public interface userService {
    //查询所有用户
    public List<User> findAll();
}
5实现userservice接口
    public class userServiceImpl  implements userService {
    private UserDao dao = new UserDaoImpl();
    @Override
    public List<User> findAll() {
        return dao.findAll();
    }
}
6创建servlet处理层
    @WebServlet("/userListServlet")
public class UserListServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //1.调用UserService完成查询
        userService service = new userServiceImpl();
        List<User> users = service.findAll();
        //2.将list存入request域
        request.setAttribute("users",users);
        //3.转发到list.jsp
        request.getRequestDispatcher("/list.jsp").forward(request,response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

   

效果

本文地址：https://blog.csdn.net/weixin_45289374/article/details/110989683