SpringMVC----RESTFUL_CRUD_修改操作
1.注意：
<!-- 对于_method不能使用form:hidden标签,因为modelAttribute对应的bean中没有_method这个属性,应该使用input标签 --> <!-- <form:hidden path="_method" value="PUT"/> -->
2.代码：
list.jsp <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> <!-- SpringMVC处理静态资源 1.为什么会有这种问题？ 优雅的REST风格的资源URL不希望带.html或.do等后缀; 若将DispatcherServlet请求映射为/,则springMVC将捕获WEB容器的所有请求,包括静态资源(图片、css、js)的请求,springMVC会将 他们当成一个普通请求处理,因此找不到对应的处理器将导致错误 2.如何解决： 在springMVC的配置文件中配置：<mvc:default-servlet-handler/>的方式解决静态资源的问题 --> <script type="text/javascript" src="scripts/jquery-1.9.1.min.js"></script> <script type="text/javascript"> $(function() { $(".delete").click(function() { var href = $(this).attr("href"); $("form").attr("action", href).submit(); return false; }); }) </script> </head> <body> <form action="" method="POST"> <input type="hidden" name="_method" value="DELETE" /> </form> <c:if test="${empty requestScope.employees }"> 没有任何员工信息. </c:if> <c:if test="${!empty requestScope.employees }"> <table border="1" cellpadding="10" cellspacing="0"> <tr> <th>ID</th> <th>LastName</th> <th>Email</th> <th>Gender</th> <th>Department</th> <th>Edit</th> <th>Delete</th> </tr> <c:forEach items="${requestScope.employees }" var="emp"> <tr> <td>${emp.id }</td> <td>${emp.lastName }</td> <td>${emp.email }</td> <td>${emp.gender == 0 ? 'Female' : 'Male' }</td> <td>${emp.department.departmentName }</td> <td><a href="emp/${emp.id}">Edit</a></td> <!-- 默认超链接是一个GET请求，但是使用HiddenHttpMethodFilter后POST请求才能转换成DELETE请求（借助js实现） --> <td><a class="delete" href="emp/${emp.id}">Delete</a></td> </tr> </c:forEach> </table> </c:if> <br> <br> <a href="emp">Add New Employee</a> </body> </html> input.jsp <%@page import="java.util.HashMap"%> <%@page import="java.util.Map"%> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body> <!-- why使用form标签 1.可以更快速的开发出表单页面，而且可以更加方便的进行表单值的回显； --> <form:form action="${pageContext.request.contextPath}/emp" method="POST" modelAttribute="employee"> <c:if test="${employee.id == null}"> <!-- path属性对应html表单标签的name属性值 --> LastName:<form:input path="lastName" /> </c:if> <c:if test="${employee.id != null}"> <form:hidden path="id" /> <input type="hidden" name="_method" value="PUT" /> </c:if> <br> email：<form:input path="email" /> <br> <% Map<String, String> genders = new HashMap(); genders.put("1", "male"); genders.put("0", "Female"); request.setAttribute("genders", genders); %> <!-- delimiter="<br>" 按照br分割 --> gender:<form:radiobuttons path="gender" items="${genders}" /> <br> Department:<form:select path="department.id" items="${departments}" itemLabel="departmentName" itemValue="id"></form:select> <br> <input type="submit" value="submit" /> </form:form> </body> </html> java代码： package com.yikuan.springmvc.crud.handlers; import java.util.Map; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import com.yikuan.springmvc.crud.dao.DepartmentDao; import com.yikuan.springmvc.crud.dao.EmployeeDao; import com.yikuan.springmvc.crud.entities.Employee; @Controller public class EmployeeHandler { @Autowired private EmployeeDao employeeDao; @Autowired private DepartmentDao departmentDao; @ModelAttribute public void getEmployee(@RequestParam(value="id",required=false)Integer id, Map<String,Object> map){ if(id != null){ map.put("employee", employeeDao.get(id)); } } @RequestMapping(value="/emp",method=RequestMethod.PUT) public String update(Employee employee){ employeeDao.save(employee); //此时修改完后，lastName为null@ModelAttribute; return "redirect:/emps"; } @RequestMapping(value="/emp/{id}",method=RequestMethod.GET) public String input(@PathVariable("id") Integer id,Map<String,Object> map){ map.put("employee", employeeDao.get(id)); /*employee必须和input.jsp中表单页面的modelAttribute="employee"值一样*/ map.put("departments", departmentDao.getDepartments()); return "input"; } @RequestMapping(value="/emp/{id}",method=RequestMethod.DELETE) public String delete(@PathVariable("id") Integer id){ employeeDao.delete(id); return "redirect:/emps"; } @RequestMapping(value="/emp",method=RequestMethod.POST) public String save(Employee employee){ employeeDao.save(employee); return "redirect:/emps"; } @RequestMapping(value="emp",method=RequestMethod.GET) public String input(Map<String,Object> map){ map.put("departments", departmentDao.getDepartments()); map.put("employee", new Employee()); return "input"; } @RequestMapping("/emps") public String list(Map<String, Object> map){ map.put("employees", employeeDao.getAll()); return "list"; } }
