SpringBoot结合jpa，监听器、thymeleaf实现监听网站的访问量

深藏阁楼爱情的钟 2022-12-16 05:53 162阅读 0赞

### SpringBoot结合jpa，监听器、thymeleaf实现监听网站的访问量 ###

*   *  1、导入依赖、进行相关配置
     *  2、创建监听表
     *  3、编写实体类
     *  4、编写业务层接口
     *  5、编写业务层接口实现类
     *  6、编写监听器
     *  7、编写控制器
     *  8、编写HTML文件，展示内容
     *  9、测试

## 1、导入依赖、进行相关配置 ##

添加jpa、thymeleaf、jdbc和java-connector的相关依赖。  
（这里没有添加版本号是因为加了spring-boot-starter-parent，可以省略一些常用依赖的版本号）

<dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-jdbc</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-jpa</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-thymeleaf</artifactId>
            </dependency>

application.properties

### mysql连接信息
    spring.datasource.url=jdbc:mysql://localhost:3306/mydb2019?serverTimezone=UTC
    spring.datasource.username=xxxx
    spring.datasource.password=xxxxxxx
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver
    
    
    ### thymeleaf模板配置
    spring.thymeleaf.mode=HTML5
    spring.thymeleaf.encoding=UTF-8
    spring.thymeleaf.cache=false
    spring.thymeleaf.prefix=classpath:/templates/
    spring.thymeleaf.suffix=.html

## 2、创建监听表 ##

监听表要实现的功能很简单，只是记录访问次数。  
![在这里插入图片描述][20201018183632713.png_pic_center]

## 3、编写实体类 ##

实体类对应监听表。具体如下：

Listener类：

/* * ye * 监听表 * 2020.10.15 * * */
    
    import javax.persistence.*;
    
    @Entity
    @Table(name = "listener")
    public class Listener { 
    
        @Id
        private String id;
        private Integer quantity;
    
        public String getId() { 
            return id;
        }
    
        public void setId(String id) { 
            this.id = id;
        }
    
        public Integer getQuantity() { 
            return quantity;
        }
    
        public void setQuantity(Integer quantity) { 
            this.quantity = quantity;
        }
    
        @Override
        public String toString() { 
            return "Listener{" +
                    "id=" + id +
                    ", quantity=" + quantity +
                    '}';
        }
    }

## 4、编写业务层接口 ##

业务层实现基本的数据表操作即可

import com.example.demojpa.model.Listener;
    import java.util.List;
    
    /* * ye * 2020.10.15 * 业务层接口 * */
    public interface ListenerService { 
        List<Listener> findAll();
        Listener findById(String id);
        Listener save(Listener listener);
        void delete(String id);
    }

## 5、编写业务层接口实现类 ##

实现业务层接口

import com.example.demojpa.model.Listener;
    import com.example.demojpa.repository.ListenerRepository;
    import com.example.demojpa.service.ListenerService;
    import org.springframework.stereotype.Service;
    
    import javax.annotation.Resource;
    import java.util.List;
    /* * ye * 2020.10.15 * 业务层接口实现类 * */
    
    @Service
    public class ListenerServiceImpl implements ListenerService { 
    
        @Resource
        private ListenerRepository listenerRepository;
    
        @Override
        public List<Listener> findAll() { 
            return listenerRepository.findAll();
        }
    
        @Override
        public Listener findById(String id) { 
            return listenerRepository.findById(id).orElse(null);
        }
    
        @Override
        public Listener save(Listener listener) { 
            return listenerRepository.save(listener);
        }
    
        @Override
        public void delete(String id) { 
            listenerRepository.deleteById(id);
        }

## 6、编写监听器 ##

编写监听器，监听请求

import com.example.demojpa.model.Listener;
    import com.example.demojpa.service.ListenerService;
    
    import javax.annotation.Resource;
    import javax.servlet.ServletRequestEvent;
    import javax.servlet.ServletRequestListener;
    import javax.servlet.annotation.WebListener;
    
    /* * ye * 2020.10.15 * 监听器 * */
    
    @WebListener
    public class PhoneListener implements ServletRequestListener { 
        @Resource
        private ListenerService listenerService;
    
        @Override
        public  void requestDestroyed(ServletRequestEvent servletRequestEvent){ 
            System.out.println("```````````````````请求listener销毁");
        }
        @Override
        public void requestInitialized(ServletRequestEvent servletRequestEvent){ 
            System.out.println("```````````````````````````````请求listener创建啊");
            Listener listener = listenerService.findById("1");
            //每次访问数量加1，并保存到数据表
            listener.setQuantity(listener.getQuantity() + 1);
            listenerService.save(listener);
        }
    
    
    }

## 7、编写控制器 ##

控制器实现对视图的控制

import com.example.demojpa.model.Listener;
    import com.example.demojpa.service.ListenerService;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.RequestMapping;
    import javax.annotation.Resource;
    /* * ye * 2020.10.15 * 控制层 * */
    
    @Controller
    public class IndexController { 
        @Resource
        private ListenerService listenerService;
    
        @RequestMapping("/count")
        public String count(Model model){ 
            Listener listener = listenerService.findById("1");
            String msg = "这是第"+listener.getQuantity()+"次访问网站！";
            model.addAttribute("count",msg);
            return "count";
        }
    }

## 8、编写HTML文件，展示内容 ##

count.html

<!DOCTYPE html>
    <html xmlns:th="http://www.thymeleaf.org">
    <html lang="en">
    <head>
        <title>count</title>
        <meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
    </head>
    <body>
    <div style="text-align: center">
        <h1 th:text="${count}"></h1>
    </div>
    </body>
    </html>

## 9、测试 ##

输入访问地址

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzUyMDY3MA_size_16_color_FFFFFF_t_70_pic_center]  
点击刷新

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzUyMDY3MA_size_16_color_FFFFFF_t_70_pic_center 1]

当然，你输入任何 http://localhost:8080/ 的端口它都能够监听的。

测试成功！

[20201018183632713.png_pic_center]: /images/20221123/81eff94094154589a8f98d29246497e0.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzUyMDY3MA_size_16_color_FFFFFF_t_70_pic_center]: /images/20221123/3c2a15aa012346e781433db467358e5c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzUyMDY3MA_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221123/922336479775489bbc8b9b5986dca430.png