Springmvc+Spring+maven+c3p0+jsp查询数据库中所有数据

Springmvc+Spring+maven+c3p0+jsp查询数据库中所有数据并显示

上篇Springmvc+Spring+maven+c3p0不加入jsp的链接
(https://blog.youkuaiyun.com/duduyingya/article/details/114992131)

1 新的项目结构

2 向pom.xml加入新需要的jar包

    <!--针对jsp页面 删除掉之前加入的servlet-api包-->

    <dependency>
      <groupId>org.glassfish.web</groupId>
      <artifactId>jstl-impl</artifactId>
      <version>1.2</version>
      <!-- 去除依赖 -->
      <exclusions>
        <exclusion>
          <groupId>javax.servlet</groupId>
          <artifactId>servlet-api</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
    <!-- 导入servlet-api -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>

2 加入一个自定义的RowMapper类

用于自定义jdbcTemplate的query方法返回的类型，制作成返回StudentBean的集合的类

package com.utilStu;

import com.db.StudentBean;

import org.springframework.jdbc.core.RowMapper;

import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * 自定义使用query时返回的实体类 类型
 */
public class StudentRowMapper implements RowMapper<StudentBean> {

	@Override
	public StudentBean mapRow(ResultSet resultSet, int i) throws SQLException {
		StudentBean studentBean=new StudentBean();
		studentBean.setId(resultSet.getInt("id"));
		studentBean.setSname(resultSet.getString("sname"));
		studentBean.setDiscri(resultSet.getString("discri"));
		studentBean.setPrice(resultSet.getDouble("price"));
		return studentBean;
	}
}

3 修改控制类和接口

package com.controller;

import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public interface StudentCon {

	ModelAndView cc(
			HttpServletRequest request, HttpServletResponse response);
}
----------------------------------------------------------------------------------------------
package com.controller;

import com.db.StudentBean;
import com.server.StudentServer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.Array;
import java.util.Arrays;
import java.util.List;
import java.util.Map;


@Controller
@RequestMapping("/user")
public class StudentConImp  implements StudentCon{


	/*
	注入业务层
	 */
	@Autowired
	public StudentServer studentServerImp;

	/**
	 * 采用get方式访问参数
	 * @return
	 * 参数 @RequestParam("userId") Integer stuId
	 */
	@RequestMapping(value = "/hello",method =RequestMethod.GET)
	@Override
	public  ModelAndView  cc(
			HttpServletRequest request, HttpServletResponse response)
	{
		List<StudentBean> stus =
				studentServerImp.selectAllSer();
		ModelAndView mav=new ModelAndView();
		mav.setViewName("success");
		mav.addObject("stus",stus);
		return mav;
	}
}

4 将持久层 业务层的查找所有的方法

返回值统一修改成 实体类集合

package com.dao;


import com.db.StudentBean;

import java.util.List;


/**
 * 数据持久层
 */

public interface StudentDao {

	/*
	查询所有
	 */
	List<StudentBean> selectAllDao();
}
---------------------------
package com.dao;


import com.db.StudentBean;
import com.utilStu.StudentRowMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;


import java.util.*;


@Component
public class StudentDaoImp implements StudentDao {


	//注入template模板 数据库操作语句模板
	@Autowired
	public JdbcTemplate jdbcTemplate;

	//单纯jdbc
	@Override
	public List<StudentBean> selectAllDao() {
		String sql="select * from stu";
		//返回实体类 集合
		List<StudentBean> stus =
				jdbcTemplate.query(sql,new StudentRowMapper());

		return stus;
	}
}
-----------------------
//业务层
package com.server;



import com.db.StudentBean;

import java.util.List;


/**
 *业务层接口类
 */
public interface StudentServer {

	//查询所有
	List<StudentBean> selectAllSer();
}
-----------------------

package com.server;

import com.dao.StudentDao;
import com.db.StudentBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;


import java.util.List;
import java.util.Map;

/**
 * 业务实现类
 */
@Service
public class StudentServerImp implements StudentServer{

	/*
	注入数据库层接口
	 */
	@Autowired
	public StudentDao studentDaoImp;

	/*
	注入同学类
	 */
	@Autowired
	public StudentBean stu;

	/*
	  得到所有同学
	 */
	@Override
	public List<StudentBean> selectAllSer() {
		return studentDaoImp.selectAllDao();

	}
}

5 修改jsp页面

1 index.jsp页面

<%@ page language="java" contentType="text/html;charset=UTF-8"  %>

<html>
<body>
<h2>Hello World!</h2>
<!--对应con层的类映射路径和方法映射路径 前面不要加斜杠-->
<form action="${pageContext.request.contextPath}/user/hello" method="get">
    <input type="submit" value="login">
</form>
</body>
</html>

2 success页面

<%@ page language="java" contentType="text/html;charset=UTF-8"  %>

<!-- 引用jstl-->
<%@ taglib uri="http://java.sun.com/jstl/core_rt" prefix="c" %><html>
<head>
    <title>Title</title>
</head>
<body>



<tr>
    <td>
        id
    </td>
    <td>
        sname
    </td>
    <td>
        discri
    </td>
    <td>
        price
    </td>
</tr>
<tr>
    <c:forEach items="${stus}" var="stulist">
       <tr>
        <td>
            ${stulist.id}
        </td>
        <td>
            ${stulist.sname}
        </td>
        <td>
                ${stulist.discri}
        </td>
        <td>
                ${stulist.price}
        </td>
</tr>
    </c:forEach>
</tr>

</body>
</html>

亲测通过的哈~

链接：
https://blog.youkuaiyun.com/ajax_yan/article/details/81452276
https://blog.youkuaiyun.com/zy103118/article/details/109492592