SpringMVC学习（五）-RESTFUl_CRUD操作

使用SpringMVC静态模仿从数据提取数据完成CRUD操作

重点知识详解：

1.将post请求改为DELETE和PUT请求（将GET请求，通过JQUERY完成转化为DELETE请求）

2.使用配置文件将get请求转换为post请求

3.静态资源问题的处理

1.Employee.java封装类

package com.springmvc.crud.entiry;

public class Employee {

private Integer id;
private String lastname;
private String email;
//1 male 0 female
private Integer gender;
private Department department;

public Employee() {
super();
// TODO Auto-generated constructor stub
}

public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getLastname() {
return lastname;
}
public void setLastname(String lastname) {
this.lastname = lastname;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Integer getGender() {
return gender;
}
public void setGender(Integer gender) {
this.gender = gender;
}
public Department getDepartment() {
return department;
}
public void setDepartment(Department department) {
this.department = department;
}

public Employee(Integer id,String lastname, String email, Integer gender, Department department) {
super();
this.id=id;
this.lastname = lastname;
this.email = email;
this.gender = gender;
this.department = department;
}

}

2.Department.java封装类

package com.springmvc.crud.entiry;

public class Department {

private Integer id;
private String departmentName;

public Department() {
super();
// TODO Auto-generated constructor stub
}

public Department(Integer id, String departmentName) {
super();
this.id = id;
this.departmentName = departmentName;
}

public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getDepartmentName() {
return departmentName;
}
public void setDepartmentName(String departmentName) {
this.departmentName = departmentName;
}

}

3.EmployeeDao.java Dao层实现

package com.springmvc.crud.dao;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import org.springframework.stereotype.Repository;

import com.springmvc.crud.entiry.Department;

@Repository
public class DepartmentDao {

private static Map<Integer, Department> departments = null;

static{
departments = new HashMap<>();
departments.put(101, new Department(101,"D-AA"));
departments.put(102, new Department(102,"D-BB"));
departments.put(103, new Department(103,"D-CC"));
departments.put(104, new Department(104,"D-DD"));
departments.put(105, new Department(105,"D-EE"));
}

public Collection<Department> getDepartment() {

return departments.values();
}
public Department getDepartment(Integer id){
return departments.get(id);
}

}

4.DepartmentDao.java Dao层实现

package com.springmvc.crud.dao;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import org.springfr
4000
amework.stereotype.Repository;

import com.springmvc.crud.entiry.Department;

@Repository
public class DepartmentDao {

private static Map<Integer, Department> departments = null;

static{
departments = new HashMap<>();
departments.put(101, new Department(101,"D-AA"));
departments.put(102, new Department(102,"D-BB"));
departments.put(103, new Department(103,"D-CC"));
departments.put(104, new Department(104,"D-DD"));
departments.put(105, new Department(105,"D-EE"));
}

public Collection<Department> getDepartment() {

return departments.values();
}
public Department getDepartment(Integer id){
return departments.get(id);
}

}

5.EmployeeHandler.java实现类

package com.springmvc.crud.handler;

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.springmvc.crud.dao.DepartmentDao;
import com.springmvc.crud.dao.EmployeeDao;
import com.springmvc.crud.entiry.Employee;

@Controller
public class EmployeeHandler {

@Autowired
private EmployeeDao employeeDao;

@Autowired
private DepartmentDao departmentDao;

@RequestMapping("/emps")
public String list(Map<String,Object> map) {
map.put("employees",employeeDao.getAll());
return "list";
}

@RequestMapping(value="/emp",method=RequestMethod.GET)
public String inputAdd(Map<String,Object> map) {
map.put("departments", departmentDao.getDepartment());
map.put("employee", new Employee());
return "input";
}

@RequestMapping(value="/emp",method=RequestMethod.POST)
public String add(Employee employee) {

employeeDao.save(employee);
return "redirect:/emps";
}

@RequestMapping(value="/emp/{id}",method=RequestMethod.DELETE)
public String delete(@PathVariable("id")Integer id){
employeeDao.delete(id);
return "redirect:/emps";
}

@RequestMapping(value="/emp/{id}",method=RequestMethod.GET)
public String inputEdit(@PathVariable("id") Integer id,Map<String,Object> map) {
map.put("employee", employeeDao.get(id));
map.put("departments", departmentDao.getDepartment());
return "input";
}

@RequestMapping(value="/emp",method=RequestMethod.PUT)
public String update(Employee employee) {
employeeDao.save(employee);
return "redirect:/emps";
}

@ModelAttribute
public void getEmployee(@RequestParam(value="id",required=false) Integer id,Map<String,Object> map) {
if(id!=null) {
map.put("employee", employeeDao.get(id));
}
}

}

6.web.xml配置

<?xml version="1.0" encoding="utf-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> 
<!--
配置org.springframework.web.filter.HiddenHttpMethodFilter：
把POST请求转为DELETE或POST请求
-->
<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>

<!-- 配置DispatcherServlet -->
<!-- 配置DispatcherServlet的作用是：如果在某个方法上配置了@RequestMapping("/helloworld")，
当浏览器访问helloworld时，DispatcherServlet会将这个请求发送给@RequestMapping("/helloworld")
所在的方法上，执行这个方法 -->
<servlet>
<servlet-name>SpringDispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<!-- 配置DispatcherServlet的一个初始化参数：配置springMVC配置文件的位置和名称 -->
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springmvc.xml</param-value>
</init-param>
<!--SpringDispatcherServlet在当前web应用被加载的时候被创建，而不是等第一次请求的时候被创建  -->
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>SpringDispatcherServlet</servlet-name>
<url-pattern>/</url-pattern>  <!-- 可以应答所有请求 -->
</servlet-mapping>

</web-app>

7.springmvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd"> <!-- 配置自动扫描的包 -->
<context:component-scan base-package="com.springmvc"></context:component-scan>

<!-- 配置视图 BeanNameViewResolver解析器：使用视图的名字来解析视图
order属性越低优先级越高
-->
<bean class="org.springframework.web.servlet.view.BeanNameViewResolver">
<property name="order" value="10" />
</bean>

<!-- 配置视图解析器：如何把handler方法返回值解析为实际视图 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/views/"/>
<property name="suffix" value=".jsp"/>
</bean>

<!-- 配置国际化资源文件 -->
<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
<property name="basename" value="i18n"></property>
</bean>

<!--  -->
<mvc:default-servlet-handler/>
<mvc:annotation-driven></mvc:annotation-driven>
</beans>

8.index.jsp页面

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!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=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<a href="emps">listAllEmployees</a>

</body>
</html>

9.list.jsp页面

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ 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=ISO-8859-1">
<title>Insert title here</title>
<!-- SpringMVC处理静态-->
<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>
<h1>hello world</h1>

<c:if test="${empty requestScope.employees }">
<h1>no employee</h1>
</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>
<td><a href="emp/${emp.id  }">Delete</a></td>
</tr>
</c:forEach>
</table>
</c:if>

<br><br>
<a href="emp">Add New Employee</a>

</body>
</html>

10.input.jsp页面

<%@page import="java.util.HashMap"%>
<%@page import="java.util.Map"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<!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>
<form:form action="${pageContext.request.contextPath }/emp" method="POST"
modelAttribute="employee"/>
<!-- path 属性对应html表单标签的name属性 -->
<form:form action="springmvc/add" method="POST" modelAttribute="employee">
<c:if test="${employee.id==null }">
LastName:<form:input path="lastname"/> <br>
</c:if>
<c:if test="${employee.id!=null }">
<form:hidden path="id"/>
<%--对于_method不能使用form：hidden标签，因为modelAttribute对应的bean中没有_method这个属性 --%>
<input type="hidden" name="_method" value="PUT">
</c:if>
Email:<form:input path="email"></form:input><br>
<%
Map<String, String> genders = new HashMap<String, String>();
genders.put("1", "male");
genders.put("0", "female");
request.setAttribute("genders", genders);
%>
Gender:<form:radiobuttons path="gender" items="${genders }"/><br>
Department:<form:select path="department"
items="${departments }" itemLabel="departmentName" itemValue="id"></form:select><br>
<input type="submit" value="Submit"/>
</form:form>

</body>
</html>