基于ssm框架的留言板代码

以下是基于SSM框架的留言板代码：

1、留言实体类Message.java：

package com.example.entity;

import java.util.Date;

public class Message {
    private Integer id;
    private String username;
    private String content;
    private Date createTime;

    public Integer getId() {
        return id;
    }

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

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }
}

2、留言Dao接口MessageDao.java：

package com.example.dao;

import com.example.entity.Message;

import java.util.List;

public interface MessageDao {
    void addMessage(Message message);
    List<Message> getMessageList();
}

3、留言Dao接口实现类MessageDaoImpl.java：

package com.example.dao.impl;

import com.example.dao.MessageDao;
import com.example.entity.Message;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import java.util.Date;
import java.util.List;

@Repository
public class MessageDaoImpl implements MessageDao {
    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Override
    public void addMessage(Message message) {
        String sql = "insert into message(username, content, create_time) values (?, ?, ?)";
        jdbcTemplate.update(sql, message.getUsername(), message.getContent(), new Date());
    }

    @Override
    public List<Message> getMessageList() {
        String sql = "select * from message order by create_time desc";
        return jdbcTemplate.query(sql, (rs, rowNum) -> {
            Message message = new Message();
            message.setId(rs.getInt("id"));
            message.setUsername(rs.getString("username"));
            message.setContent(rs.getString("content"));
            message.setCreateTime(rs.getTimestamp("create_time"));
            return message;
        });
    }
}

4、留言Service接口MessageService.java：

package com.example.service;

import com.example.entity.Message;

import java.util.List;

public interface MessageService {
    void addMessage(Message message);
    List<Message> getMessageList();
}

5、留言Service接口实现类MessageServiceImpl.java：

package com.example.service.impl;

import com.example.dao.MessageDao;
import com.example.entity.Message;
import com.example.service.MessageService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class MessageServiceImpl implements MessageService {
    @Autowired
    private MessageDao messageDao;

    @Override
    public void addMessage(Message message) {
        messageDao.addMessage(message);
    }

    @Override
    public List<Message> getMessageList() {
        return messageDao.getMessageList();
    }
}

6、控制器MessageController.java：

package com.example.controller;

import com.example.entity.Message;
import com.example.service.MessageService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import java.util.List;

@Controller
public class MessageController {
    @Autowired
    private MessageService messageService;

    @RequestMapping(value = "/add", method = RequestMethod.POST)
    public String addMessage(Message message) {
        messageService.addMessage(message);
        return "redirect:/list";
    }

    @RequestMapping(value = "/list", method = RequestMethod.GET)
    public String getMessageList(ModelMap modelMap) {
        List<Message> messageList = messageService.getMessageList();
        modelMap.addAttribute("messageList", messageList);
        return "list";
    }
}

7、留言界面add.jsp：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>添加留言</title>
</head>
<body>
<h3>添加留言</h3>
<form action="${pageContext.request.contextPath}/add" method="post">
    用户名：<input type="text" name="username"><br>
    内容：<input type="text" name="content"><br>
    <input type="submit" value="提交">
</form>
</body>
</html>

8、留言列表界面list.jsp：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>留言列表</title>
</head>
<body>
<h3>留言列表</h3>
<a href="${pageContext.request.contextPath}/add">添加留言</a><br><br>
<table border="1">
    <tr>
        <td>用户名</td>
        <td>留言内容</td>
        <td>留言时间</td>
    </tr>
    <c:forEach var="message" items="${messageList}">
        <tr>
            <td>${message.username}</td>
            <td>${message.content}</td>
            <td>${message.createTime}</td>
        </tr>
    </c:forEach>
</table>
</body>
</html>

以上就是基于SSM框架的留言板代码。