SpringMvc学习-增删改查
本节主要介绍SpringMVC简单的增删改查功能。
1.查询
dao中的代码
1 public List<WeatherPojo> getAllWeather(){ 2 3 String sql="select * from weathertest"; 4 List<WeatherPojo> pojos=new ArrayList<WeatherPojo>(); 5 pojos= jdbcTemplate.query(sql,new RowMapper() { 6 7 @Override 8 public Object mapRow(ResultSet rs, int arg1) throws SQLException { 9 // TODO Auto-generated method stub 10 WeatherPojo weather=new WeatherPojo(); 11 weather.setName(rs.getString("name")); 12 weather.setPassword(rs.getString("password")); 13 weather.setId(rs.getInt("id")); 14 return weather; 15 } 16 }); 17 return pojos; 18 }
同事,还可以写service和serviceimpl。需要对jdmctempl添加注解
@Autowired
private JdbcTemplate jdbcTemplate;
在impl中需要对dao添加注解
@Autowired
private WeatherDao weatherDao;
在controller中调用服务
1 @Autowired 2 private WeatherServiceImpl weatherService; 3 @RequestMapping(params="method=query") 4 public ModelAndView getAllWeather(HttpServletRequest request,HttpServletResponse response){ 5 List<WeatherPojo> pojos=weatherService.getWeatherList(); 6 request.setAttribute("weathers", pojos); 7 System.out.println(pojos.get(0).getName()); 8 return new ModelAndView("weatherlist"); 9 }
通过modelandview返回页面,页面代码如下:
1 <%@ page language="java" contentType="text/html; charset=utf-8" 2 pageEncoding="utf-8"%> 3 <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> 4 <%String path = request.getContextPath(); 5 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 6 %> 7 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 8 <html> 9 <head> 10 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 11 <title>Insert title here</title> 12 </head> 13 <body> 14 <div><a href="<%=basePath %>weather.do?method=add">添加</a></div> 15 <div> 16 <table> 17 <thead> 18 <tr> 19 <th>姓名</th> 20 <th>说明</th> 21 <th>操作</th> 22 </tr> 23 </thead> 24 <tbody> 25 <c:forEach var="item" items="${weathers}"> 26 <tr> 27 <td>${item.name }</td> 28 <td>${item.password }</td> 29 <td></td> 30 <td><a href="<%=basePath %>weather.do?method=edit&id=${item.id}">编辑</a><a href="<%=basePath %>weather.do?method=delete&id=${item.id}">删除</a></td> 31 </tr> 32 </c:forEach> 33 </tbody> 34 </table> 35 </div> 36 </body> 37 </html>
2.增加
dao中代码
1 public void addWeather(WeatherPojo weather){ 2 String sql="insert into weathertest(id,name,password) values("+weather.getId()+",'"+weather.getName()+"','"+weather.getPassword()+"')"; 3 jdbcTemplate.execute(sql); 4 }
controller代码,get方法是进入新增页面,页面传递空对象。post方法为添加新的记录
1 @RequestMapping(params="method=add",method=RequestMethod.GET) 2 public ModelAndView addWeather(HttpServletRequest request,HttpServletResponse reponse){ 3 4 request.setAttribute("weather", new WeatherPojo()); 5 return new ModelAndView("weatheradd"); 6 } 7 @RequestMapping(params="method=add",method=RequestMethod.POST) 8 public ModelAndView addWeather(WeatherPojo weather){ 9 10 weatherService.addWeather(weather); 11 return new ModelAndView("redirect:/weather.do?method=query"); 12 }
jsp页面代码
1 <%@ page language="java" contentType="text/html; charset=utf-8" 2 pageEncoding="utf-8"%> 3 <%String path = request.getContextPath(); 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 5 %> 6 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 7 <html> 8 <head> 9 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 10 <title>Insert title here</title> 11 </head> 12 <body> 13 <form action="<%=basePath%>weather.do?method=add" method="post"> 14 <label for="id">id</label> 15 <input name="id"/><br> 16 <label for="name">name</label> 17 <input name="name"><br> 18 <label for="password">password</label> 19 <input name="password"><br> 20 <input type="submit" value="提交"> 21 </form> 22 </body> 23 </html>
3.修改
dao中代码:
1 public void editWeather(WeatherPojo weather){ 2 String sql="update weathertest set name='"+weather.getName()+"',password='"+weather.getPassword()+"' where id="+weather.getId()+""; 3 jdbcTemplate.execute(sql); 4 }
controller代码
1 @RequestMapping(params="method=edit",method=RequestMethod.GET) 2 public ModelAndView editWeather(HttpServletRequest request,HttpServletResponse response){ 3 4 int id=Integer.valueOf(request.getParameter("id")); 5 WeatherPojo weather=new WeatherPojo(); 6 weather=weatherService.getWeatherById(id); 7 ModelAndView mav=new ModelAndView("editweather"); 8 request.setAttribute("weather", weather); 9 System.out.println("--------"+weather.getId()); 10 System.out.println("--------"+weather.getName()); 11 System.out.println("--------"+weather.getPassword()); 12 return mav; 13 } 14 @RequestMapping(params="method=edit",method=RequestMethod.POST) 15 public ModelAndView editWeather(WeatherPojo weather){ 16 weatherService.editWeather(weather); 17 return new ModelAndView("redirect:/weather.do?method=query"); 18 }
jsp页面:
1 <%@ page language="java" contentType="text/html; charset=utf-8" 2 pageEncoding="utf-8"%> 3 <%String path = request.getContextPath(); 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 5 %> 6 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 7 <html> 8 <head> 9 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 10 <title>Insert title here</title> 11 </head> 12 <body> 13 <form action="<%=basePath%>weather.do?method=edit" method="post"> 14 <label for="id">id</label> 15 <input name="id" readonly="true" value="${weather.id }"/><br> 16 <label for="name">name</label> 17 <input name="name" value="${weather.name }"><br> 18 <label for="password" >password</label> 19 <input name="password" value="${weather.password }"><br> 20 <input type="submit" value="提交"> 21 </form> 22 </body> 23 </html>
4.删除
dao中代码:
//delete public void deleteWeather(int id){ String sql="delete from weathertest where id="+id; jdbcTemplate.execute(sql); }
controller代码:
@RequestMapping(params="method=delete",method=RequestMethod.GET) public ModelAndView deleteWeather(HttpServletRequest request,HttpServletResponse response){ int id=Integer.valueOf(request.getParameter("id")); weatherService.deleteWeather(id); //页面重定向 return new ModelAndView("redirect:/weather.do?method=query"); }
jsp代码:
1 <%@ page language="java" contentType="text/html; charset=utf-8" 2 pageEncoding="utf-8"%> 3 <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> 4 <%String path = request.getContextPath(); 5 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 6 %> 7 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 8 <html> 9 <head> 10 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 11 <title>Insert title here</title> 12 </head> 13 <body> 14 <div><a href="<%=basePath %>weather.do?method=add">添加</a></div> 15 <div> 16 <table> 17 <thead> 18 <tr> 19 <th>姓名</th> 20 <th>说明</th> 21 <th>操作</th> 22 </tr> 23 </thead> 24 <tbody> 25 <c:forEach var="item" items="${weathers}"> 26 <tr> 27 <td>${item.name }</td> 28 <td>${item.password }</td> 29 <td></td> 30 <td><a href="<%=basePath %>weather.do?method=edit&id=${item.id}">编辑</a><a href="<%=basePath %>weather.do?method=delete&id=${item.id}">删除</a></td> 31 </tr> 32 </c:forEach> 33 </tbody> 34 </table> 35 </div> 36 </body> 37 </html>
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