1.1.?概述

當提交的表單帶有_method字段時,通過HiddenHttpMethodFilter?將?POST?請求轉換成?DELETE、PUT請求,加上@PathVariable注解從而實現?RESTful?風格的CRUD

1.2.?配置信息

Web.xml

<?

xml version="1.0" encoding="UTF-8"?

> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0" > <!-- The front controller of this Spring Web application, responsible for handling all application requests --> <servlet> <servlet-name>springDispatcherServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <!-- Map all requests to the DispatcherServlet for handling --> <servlet-mapping> <servlet-name>springDispatcherServlet</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <!--配置 HiddenHttpMethodFilter 能夠將 POST 請求轉為 DELETE、PUT 請求 --> <filter> <filter-name>hiddenHttpMethodFilter</filter-name> <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class> </filter> <filter-mapping> <filter-name>hiddenHttpMethodFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app>

1.3.?效果

①?通過POST?請求添加員工信息

②?通過PUT?請求改動員工信息

③?通過DELETE?請求刪除員工信息

④?通過GET?請求?獲取全部的?員工信息

1.4.?代碼

Employee.java

package com.ibigsea.springmvc.model;public class Employee {private Integer id;private String name;private String email;private int sex;private Department department;public Employee(Integer id, String name, String email, int sex,Department department) {super();this.id = id;this.name = name;this.email = email;this.sex = sex;this.department = department;}public Employee() {super();}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}public int getSex() {return sex;}public void setSex(int sex) {this.sex = sex;}public Department getDepartment() {return department;}public void setDepartment(Department department) {this.department = department;}@Overridepublic String toString() {return "Employee [id=" + id + ", name=" + name + ", email=" + email+ ", sex=" + sex + ", department=" + department + "]";}}

Department.java

package com.ibigsea.springmvc.model;import java.io.Serializable;public class Department implements Serializable {private static final long serialVersionUID = 6881984318733090395L;private Integer id;private String name;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}@Overridepublic String toString() {return "Department [id=" + id + ", name=" + name + "]";}}

RestfulController.java

package com.ibigsea.springmvc.rest;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.ibigsea.springmvc.dao.DepartmentDao; import com.ibigsea.springmvc.dao.EmployeeDao; import com.ibigsea.springmvc.model.Employee;/*** 基于Restful風格的增刪改查* @author bigsea*/ @Controller @RequestMapping("/restful") public class RestfulController {@Autowiredprivate EmployeeDao employeeDao;@Autowiredprivate DepartmentDao departmentDao;/*** 由于改動的時候不能改動員工姓名,* 所以通過 @ModelAttribute 注解,* 表示在運行目標方法時,先獲取該員工對象* 將員工對象存入 implicitMode 中* @param id 員工ID* @param map 實際傳入的是implicitMode*/@ModelAttributepublic void getEmployee(@RequestParam(value="id",required=false) Integer id,Map<String,Object> map){if (id != null) {map.put("employee", employeeDao.getEmpById(id));}}/*** 查看全部的員工信息* @param map* @return*/@RequestMapping("/list")public String list(Map<String, Object> map){map.put("emps", employeeDao.getAll());return "list";}/*** 跳轉到員工加入頁面* @param map* @return*/@RequestMapping(value="/add",method=RequestMethod.GET)public String add(Map<String, Object> map){map.put("depts", departmentDao.getAll());map.put("action", "add");return "emp";}/*** 加入員工* @param emp* @return*/@RequestMapping(value="/add",method=RequestMethod.POST)public String add(Employee emp){if (emp == null) {return "emp";}if (emp.getDepartment().getId() != null) {emp.setDepartment(departmentDao.getDepartmentById(emp.getDepartment().getId()));}employeeDao.save(emp);return "redirect:/restful/list";}/*** 刪除員工信息* @param id* @return*/@RequestMapping(value="/delete/{id}",method=RequestMethod.DELETE)public String delete(@PathVariable("id") Integer id){employeeDao.delEmpById(id);return "redirect:/restful/list";}/*** 由于先運行了 @ModelAttribute 注解的方法,* 獲取了該員工ID所相應的員工信息* 然后在將前臺獲取的員工數據存入獲取的員工信息中,* 這樣就不用提交name屬性也能夠獲取到值* @param emp* @return*/@RequestMapping(value="/edit",method=RequestMethod.PUT)public String edit(Employee emp){if (emp == null) {return "emp";}if (emp.getDepartment().getId() != null) {emp.setDepartment(departmentDao.getDepartmentById(emp.getDepartment().getId()));}employeeDao.save(emp);return "redirect:/restful/list";}/*** 跳轉到員工改動頁面* @param id 員工ID* @param map implicitMode* @return */@RequestMapping(value="/edit/{id}",method=RequestMethod.GET)public String edit(@PathVariable("id") Integer id,Map<String, Object> map){map.put("emp", employeeDao.getEmpById(id));map.put("depts", departmentDao.getAll());map.put("action", "edit");return "emp";}}

EmployeeDao.java

package com.ibigsea.springmvc.dao;import java.util.Collection; import java.util.HashMap; import java.util.Map;import org.springframework.stereotype.Component;import com.ibigsea.springmvc.model.Department; import com.ibigsea.springmvc.model.Employee;@Component public class EmployeeDao {private static Map<Integer,Employee> emps = new HashMap<Integer, Employee>();/*** 初始化員工信息*/static {emps.put(1001, new Employee(1001,"AA","AA@ibigsea.com",0,new Department(101, "JAVA")));emps.put(1002, new Employee(1002,"BB","BB@ibigsea.com",0,new Department(102, ".NET")));emps.put(1003, new Employee(1003,"CC","CC@ibigsea.com",1,new Department(103, "PHP")));emps.put(1004, new Employee(1004,"DD","DD@ibigsea.com",0,new Department(104, "C")));}private static int employeeId = 1005;/*** 保存員工信息* @param emp*/public void save(Employee emp){if (emp.getId() == null) {emp.setId(employeeId++);}emps.put(emp.getId(), emp);}/*** 獲取全部的員工信息* @return*/public Collection<Employee> getAll(){return emps.values();}/*** 依據ID獲取員工信息* @param id* @return*/public Employee getEmpById(Integer id){return emps.get(id);}/*** 依據ID刪除員工信息* @param id*/public void delEmpById(Integer id){emps.remove(id);}}

DepartmentDao.java

package com.ibigsea.springmvc.dao;import java.util.Collection; import java.util.HashMap; import java.util.Map;import org.springframework.stereotype.Component;import com.ibigsea.springmvc.model.Department;@Component public class DepartmentDao {public static Map<Integer, Department> depts = new HashMap<Integer, Department>();/*** 初始化部門信息*/static {depts.put(101, new Department(101,"JAVA"));depts.put(102, new Department(102,".NET"));depts.put(103, new Department(103,"PHP"));depts.put(104, new Department(104,"C"));}/*** 獲取全部的部門信息* @return*/public Collection<Department> getAll(){return depts.values();}/*** 依據ID獲取部門信息* @param id* @return*/public Department getDepartmentById(Integer id){return depts.get(id);}}

List.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%> <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> <!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>員工信息</title> </head> <body><c:if test="${ empty emps }">沒有員工信息</c:if><c:if test="${ !empty emps }"><table border="1" bordercolor="black" cellspacing="0"><tr><td width="40px">id</td><td width="30px">name</td><td width="80px">email</td><td width="30px">sex</td><td width="40px">編輯</td><td width="40px">刪除</td></tr><c:forEach items="${emps }" var="emp"><tr><td>${emp.id }</td><td>${emp.name }</td><td>${emp.email }</td><td>${emp.sex == 0 ? '男' : '女'}</td><td><a href="${pageContext.request.contextPath}/restful/edit/${emp.id }">Edit</a></td><td><form action="${pageContext.request.contextPath}/restful/delete/${emp.id }" method="post"><input type="hidden" name="_method" value="DELETE"><input type="submit" value="Delete"></form></td></tr></c:forEach></table></c:if><br><br><a href="${pageContext.request.contextPath}/restful/add">加入員工</a> </body> </html>

Emp.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%> <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> <!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>員工信息</title> </head> <body><form action="${pageContext.request.contextPath}/restful/${action}" method="post"><c:if test="${!empty emp}"><input type="hidden" name="_method" value="PUT"><input type="hidden" name="id" value="${emp.id }"><br/><br/></c:if><c:if test="${empty emp}">name : <input type="text" name="name" value="${emp.name }"><br/><br/></c:if>email : <input type="text" name="email" value="${emp.email }"><br/><br/>sex :<input type="radio" name="sex" value="0" <c:if test="${emp.sex == 0}">checked</c:if>>男 ??<input type="radio" name="sex" value="1" <c:if test="${emp.sex == 1}">checked</c:if>>女<br/><br/>department :<select name="department.id"><c:forEach items="${depts }" var="dept"><option value="${dept.id }" <c:if test="${emp.department.id == dept.id}">selected</c:if>>${dept.name }</option></c:forEach></select><br><br/><input type="submit" value="提交"></form> </body> </html>

1.5.?靜態資源問題

由于配置了DispatcherServlet而且攔截了全部的請求,所以在加入靜態資源的時候會訪問不到靜態資源,在springMVC.xml配置

mvc:default-servlet-handler

將在?SpringMVC?上下文中定義一個DefaultServletHttpRequestHandler，它會對進入?DispatcherServlet?的請求進行篩查，假設發現是沒有經過映射的請求，就將該請求交由?WEB應用server默認的?Servlet?處理。假設不是靜態資源的請求。才由DispatcherServlet?繼續處理

mvc:annotation-driven

會自己主動注冊

RequestMappingHandlerMapping

RequestMappingHandlerAdapter?

ExceptionHandlerExceptionResolver?三個bean。

就能訪問到靜態資源了

1.6.?mvc:annotation-driven和mvc:default-servlet-handler

在配置SpringMVC配置文件時加入mvc:annotation-driven

<mvc:annotation-driven?/>?會自己主動注冊三個Bean

2?RequestMappingHandlerMapping

2?RequestMappingHandlerAdapter?

2?ExceptionHandlerExceptionResolver?

還將提供下面支持：

–?支持使用?ConversionService?實例對表單參數進行類型轉換

–?支持使用?@NumberFormat?、@DateTimeFormat注解完畢數據類型的格式化

–?支持使用?@Valid?注解對?JavaBean?實例進行?JSR?303?驗證

–?支持使用?@RequestBody?和?@ResponseBody?注解

轉載于:https://www.cnblogs.com/jzdwajue/p/7137280.html

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