當前位置：首頁 > 编程语言 > c/c++ >内容正文

c/c++

springMVC3.0（文件上传，@RequestMapping加参数,@SessionAttributes,@ModelAttribute，转发，重定向，数值获取，传参，ajax,拦截器)

發布時間：2024/9/27 c/c++ 27 豆豆

生活随笔收集整理的這篇文章主要介紹了 springMVC3.0（文件上传，@RequestMapping加参数,@SessionAttributes,@ModelAttribute，转发，重定向，数值获取，传参，ajax,拦截器) 小編覺得挺不錯的,現在分享給大家,幫大家做個參考.

1.項目包結構如下：

2.?????? spring配置文件springMVC.xml修改如下：

3.?????? spring配置文件beans.xml內容修改如下：

<?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:mvc="http://www.springframework.org/schema/mvc"
?xmlns:context="http://www.springframework.org/schema/context"
?xmlns:aop="http://www.springframework.org/schema/aop"
?xmlns:tx="http://www.springframework.org/schema/tx"
?xsi:schemaLocation="http://www.springframework.org/schema/beans
??????http://www.springframework.org/schema/beans/spring-beans.xsd
??????http://www.springframework.org/schema/mvc
??????http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
??????http://www.springframework.org/schema/context
??????http://www.springframework.org/schema/context/spring-context-3.0.xsd
??????http://www.springframework.org/schema/aop
??????http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
??????http://www.springframework.org/schema/tx
??????http://www.springframework.org/schema/tx/spring-tx-3.0.xsd ">
?
?<mvc:annotation-driven/>
?
?<context:component-scan base-package="com.sxt.web"></context:component-scan>
?
?
?<bean id="ds" class="com.mchange.v2.c3p0.ComboPooledDataSource">
??<property name="driverClass" value="com.mysql.jdbc.Driver"></property>
??<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/springmvc"></property>
??<property name="user" value="root"></property>
??<property name="password" value="123456"></property>
??<property name="initialPoolSize" value="10"></property>
??<property name="maxPoolSize" value="50"></property>
??<property name="minPoolSize" value="10"></property>
?</bean>
?
?<bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
??<property name="dataSource" ref="ds"></property>
??
??
??<property name="mappingDirectoryLocations">
???<value>classpath:com/sxt/domain/</value>
??</property>
??<property name="hibernateProperties">
???<props>
????<prop key="hibernate.Dialect">org.hibernate.dialect.MySQLInnoDBDialect</prop>
????<prop key="hibernate.show_sql">true</prop>
????<prop key="hibernate.hbm2ddl.auto">update</prop>
???</props>
??</property>
?</bean>
?
?
?<bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
??<property name="sessionFactory" ref="sessionFactory"/>
?</bean>
?
?
?<tx:advice id="txAdvice" transaction-manager="txManager">
??<tx:attributes>
???<tx:method name="save*" propagation="REQUIRED"/>
???<tx:method name="delete*" propagation="REQUIRED"/>
???<tx:method name="update*" propagation="REQUIRED"/>
???<tx:method name="find*" read-only="true"/>
???<tx:method name="*" read-only="true"/>
??</tx:attributes>
?</tx:advice>
?
?<aop:config>
??<aop:advisor pointcut="execution(* *..*ServiceImpl.*(..))" advice-ref="txAdvice"/>
??
?</aop:config>
</beans>

4.?????? web.xml文件不變

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
?xmlns="http://java.sun.com/xml/ns/j2ee"
?xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
?xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
?http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
?
?
?<context-param>
??<param-name>contextConfigLocation</param-name>
??<param-value>classpath:beans.xml</param-value>
?</context-param>
?<listener>
??<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
?</listener>
?
?<servlet>
??<servlet-name>action</servlet-name>
??<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
??<init-param>
???<param-name>contextConfigLocation</param-name>
???<param-value>classpath:springMVC.xml</param-value>
??</init-param>
?</servlet>
?<servlet-mapping>
??<servlet-name>action</servlet-name>
??<url-pattern>/</url-pattern>
?</servlet-mapping>
? <welcome-file-list>
??? <welcome-file>index.jsp</welcome-file>
? </welcome-file-list>
</web-app>

5.?????? 類的代碼不變。

6.?????? 運行，測試。跟上一個項目保持一致。

Spring MVC 3.0 深入

核心原理

1.?????? 用戶發送請求給服務器。url：user.do

2.?????? 服務器收到請求。發現DispatchServlet可以處理。于是調用DispatchServlet。

3.?????? DispatchServlet內部，通過HandleMapping檢查這個url有沒有對應的Controller。如果有，則調用Controller。

4.??????Controller開始執行。

5.?????? Controller執行完畢后，如果返回字符串，則ViewResolver將字符串轉化成相應的視圖對象；如果返回ModelAndView對象，該對象本身就包含了視圖對象信息。

6.?????? DispatchServlet將執視圖對象中的數據，輸出給服務器。

7.?????? 服務器將數據輸出給客戶端。

spring3.0中相關jar包的含義

org.springframework.aop-3.0.3.RELEASE.jar	spring的aop面向切面編程
org.springframework.asm-3.0.3.RELEASE.jar	spring獨立的asm字節碼生成程序
org.springframework.beans-3.0.3.RELEASE.jar	IOC的基礎實現
org.springframework.context-3.0.3.RELEASE.jar	IOC基礎上的擴展服務
org.springframework.core-3.0.3.RELEASE.jar	spring的核心包
org.springframework.expression-3.0.3.RELEASE.jar	spring的表達式語言
org.springframework.web-3.0.3.RELEASE.jar	web工具包
org.springframework.web.servlet-3.0.3.RELEASE.jar	mvc工具包

@Controller控制器定義

和Struts1一樣，Spring的Controller是Singleton的。這就意味著會被多個請求線程共享。因此，我們將控制器設計成無狀態類。

在spring 3.0中，通過@controller標注即可將class定義為一個controller類。為使spring能找到定義為controller的bean,需要在spring-context配置文件中增加如下定義：

<context:component-scan base-package="com.sxt.web"/>

????????注：實際上，使用@component，也可以起到@Controller同樣的作用。

@RequestMapping

??? 在類前面定義，則將url和類綁定。

??????在方法前面定義，則將url和類的方法綁定，如下所示：

package com.sxt.web;

import javax.annotation.Resource;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import com.sxt.service.UserService;

@Controller

@RequestMapping("/user.do")

publicclass UserController?{

??? @Resource

??? private UserServiceuserService;

???

??? //http://localhost:8080/springmvc02/user.do?method=reg&uname=zzzz

??? @RequestMapping(params="method=reg")

??? public String reg(String uname) {

?????? System.out.println("HelloController.handleRequest()");

?????? userService.add(uname);

?????? return"index";

??? }

???

??? public UserService getUserService() {

?????? returnuserService;

??? }

??? publicvoid setUserService(UserService userService) {

?????? this.userService = userService;

??? }

???

}

@RequestParam

???????? 一般用于將指定的請求參數賦給方法中形參。示例代碼如下：

????????

@RequestMapping(params="method=reg5")

??? public String reg5(@RequestParam("name")String uname,ModelMap map) {

?????? System.out.println("HelloController.handleRequest()");

?????? System.out.println(uname);

??????? //通過ModelMap傳參

??????? map.put("name", uname);?????

??????? return"index";

??? }

????????

???????? 這樣，就會將name參數的值付給uname。當然，如果請求參數名稱和形參名稱保持一致，則不需要這種寫法。

@SessionAttributes

??? 將ModelMap中指定的屬性放到session中。示例代碼如下：

???

@Controller

@RequestMapping("/user.do")

@SessionAttributes({"u","a"})??//將ModelMap中屬性名字為u、a的再放入session中。這樣，request和session中都有了。

publicclass UserController?{

??? @RequestMapping(params="method=reg4")

??? public String reg4(ModelMap map) {??? ??? System.out.println("HelloController.handleRequest()");

?????? map.addAttribute("u","uuuu");?//將u放入request作用域中，這樣轉發頁面也可以取到這個數據。

?????? return"index";

??? }

}

? <body>

?? <h1>**********${requestScope.u.uname}</h1>

?? <h1>**********${sessionScope.u.uname}</h1>

? </body>

???

??? 注：名字為”user”的屬性再結合使用注解@SessionAttributes可能會報錯。

@ModelAttribute

?????這個注解可以跟@SessionAttributes配合在一起用。可以將ModelMap中屬性的值通過該注解自動賦給指定變量。

??? 示例代碼如下：

package com.sxt.web;

import javax.annotation.Resource;

import org.springframework.stereotype.Controller;

import org.springframework.ui.ModelMap;

import org.springframework.web.bind.annotation.ModelAttribute;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.SessionAttributes;

@Controller

@RequestMapping("/user.do")

@SessionAttributes({"u","a"})?

publicclass UserController?{

???

??? @RequestMapping(params="method=reg4")

??? public String reg4(ModelMap map) {

?????? System.out.println("HelloController.handleRequest()");

?????? map.addAttribute("u","尚學堂高淇");

?????? return"index";

??? }

???

??? @RequestMapping(params="method=reg5")

public String reg5(@ModelAttribute("u")String uname?,ModelMap map) {

?????? System.out.println("HelloController.handleRequest()");

?????? System.out.println(uname);

??? ??? return"index";

??? }

???

}

先調用reg4方法，再調用reg5方法。我們發現控制臺打印出來：尚學堂高淇

Controller類中方法參數的處理

Controller類中方法返回值的處理

1.?????? 返回string(建議)

a)???????? 根據返回值找對應的顯示頁面。路徑規則為：prefix前綴+返回值+suffix后綴組成

b)???????? 代碼如下：

@RequestMapping(params="method=reg4")

??? public String reg4(ModelMap map) {

?????? System.out.println("HelloController.handleRequest()");

?????? return"index";

??? }

前綴為：/WEB-INF/jsp/???后綴是：.jsp

在轉發到：/WEB-INF/jsp/index.jsp

2.?????? 也可以返回ModelMap、ModelAndView、map、List、Set、Object、無返回值。一般建議返回字符串！

請求轉發和重定向

???????? 代碼示例：

????????

package com.sxt.web;

import javax.annotation.Resource;

import org.springframework.stereotype.Controller;

import org.springframework.ui.ModelMap;

import org.springframework.web.bind.annotation.ModelAttribute;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.SessionAttributes;

@Controller

@RequestMapping("/user.do")

publicclass UserController?{

???

??? @RequestMapping(params="method=reg4")

??? public String reg4(ModelMap map) {

?????? System.out.println("HelloController.handleRequest()");

//???? return "forward:index.jsp";

//???? return "forward:user.do?method=reg5"; //轉發

//???? return "redirect:user.do?method=reg5";? //重定向

?????? return"redirect:http://www.baidu.com";?//重定向

??? }

???

??? @RequestMapping(params="method=reg5")

??? public String reg5(String uname,ModelMap map) {

?????? System.out.println("HelloController.handleRequest()");

?????? System.out.println(uname);

?????? return"index";

??? }

???

}

????????

???????? 訪問reg4方法，既可以看到效果。

獲得request對象、session對象

普通的Controller類，示例代碼如下：

@Controller

@RequestMapping("/user.do")

publicclass UserController?{

???

??? @RequestMapping(params="method=reg2")

??? public String reg2(String uname,HttpServletRequest req,ModelMap map){

?????? req.setAttribute("a","aa");

?????? req.getSession().setAttribute("b","bb");

?????? return"index";

??? }

}

ModelMap

???????? 是map的實現，可以在其中存放屬性，作用域同request。下面這個示例，我們可以在modelMap中放入數據，然后在forward的頁面上顯示這些數據。通過el表達式、JSTL、java代碼均可。代碼如下：

????????

package com.sxt.web;

import org.springframework.stereotype.Controller;

import org.springframework.ui.ModelMap;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.servlet.mvc.multiaction.MultiActionController;

@Controller

@RequestMapping("/user.do")

publicclass UserControllerextends MultiActionController?{

???

??? @RequestMapping(params="method=reg")

??? public String reg(String uname,ModelMap map){

?????? map.put("a","aaa");

?????? return"index";

??? }

}

<%@ page language="java"import="java.util.*"pageEncoding="utf-8"%>

<%@ taglib prefix="c"uri="http://java.sun.com/jsp/jstl/core"%>

<!DOCTYPEHTMLPUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

? <head></head>

? <body>

??? ?? <h1>${requestScope.a}</h1>

??? ?? <c:out value="${requestScope.a}"></c:out>

? </body>

</html>

ModelAndView模型視圖類

見名知意，從名字上我們可以知道ModelAndView中的Model代表模型，View代表視圖。即，這個類把要顯示的數據存儲到了Model屬性中，要跳轉的視圖信息存儲到了view屬性。我們看一下ModelAndView的部分源碼，即可知其中關系：

publicclassModelAndView {

??? /** View instance or view name String */

??? private Objectview;

??? /** Model Map */

??? private ModelMapmodel;

??? /**

??? ?* Indicates whether or not this instance has been cleared with a call to{@link #clear()}.

??? ?*/

??? privatebooleancleared =false;

??? /**

??? ?* Default constructor for bean-style usage: populating bean

??? ?* properties instead of passing in constructor arguments.

??? ?* @see #setView(View)

??? ?* @see #setViewName(String)

??? ?*/

??? public ModelAndView() {

??? }

??? /**

??? ?* Convenient constructor when there is no model data to expose.

??? ?* Can also be used in conjunction with<code>addObject</code>.

??? ?* @param viewName name of the View to render, to be resolved

??? ?* by the DispatcherServlet's ViewResolver

??? ?* @see #addObject

??? ?*/

??? public ModelAndView(String viewName) {

?????? this.view = viewName;

??? }

??? /**

??? ?* Convenient constructor when there is no model data to expose.

??? ?* Can also be used in conjunction with<code>addObject</code>.

??? ?* @param view View object to render

??? ?* @see #addObject

??? ?*/

??? public ModelAndView(View view) {

?????? this.view = view;

??? }

??? /**

??? ?* Creates new ModelAndView given a view name and a model.

??? ?* @param viewName name of the View to render, to be resolved

??? ?* by the DispatcherServlet's ViewResolver

??? ?* @param model Map of model names (Strings) to model objects

??? ?* (Objects). Model entries may not be<code>null</code>, but the

??? ?* model Map may be <code>null</code> if there is no model data.

??? ?*/

??? public ModelAndView(String viewName, Map<String, ?> model) {

?????? this.view = viewName;

?????? if (model !=null) {

?????????? getModelMap().addAllAttributes(model);

?????? }

??? }

??? /**

??? ?* Creates new ModelAndView given a View object and a model.

??? ?* <emphasis>Note: the supplied model data is copied into the internal

??? ?* storage of this class. You should not consider to modify the supplied

??? ?* Map after supplying it to this class</emphasis>

??? ?* @param view View object to render

??? ?* @param model Map of model names (Strings) to model objects

??? ?* (Objects). Model entries may not be<code>null</code>, but the

??? ?* model Map may be <code>null</code> if there is no model data.

??? ?*/

??? public ModelAndView(View view, Map<String, ?> model) {

?????? this.view = view;

?????? if (model !=null) {

?????????? getModelMap().addAllAttributes(model);

?????? }

??? }

??? /**

??? ?* Convenient constructor to take a single model object.

??? ?* @param viewName name of the View to render, to be resolved

??? ?* by the DispatcherServlet's ViewResolver

??? ?* @param modelName name of the single entry in the model

??? ?* @param modelObject the single model object

??? ?*/

??? public ModelAndView(String viewName, String modelName, Object modelObject) {

?????? this.view = viewName;

?????? addObject(modelName, modelObject);

??? }

??? /**

??? ?* Convenient constructor to take a single model object.

??? ?* @param view View object to render

??? ?* @param modelName name of the single entry in the model

??? ?* @param modelObject the single model object

??? ?*/

??? public ModelAndView(View view, String modelName, Object modelObject) {

?????? this.view = view;

?????? addObject(modelName, modelObject);

??? }

??? /**

??? ?* Set a view name for this ModelAndView, to be resolved by the

??? ?* DispatcherServlet via a ViewResolver. Will override any

??? ?* pre-existing view name or View.

??? ?*/

??? publicvoid setViewName(String viewName) {

?????? this.view = viewName;

??? }

??? /**

??? ?* Return the view name to be resolved by the DispatcherServlet

??? ?* via a ViewResolver, or <code>null</code> if we are using a View object.

??? ?*/

??? public String getViewName() {

?????? return (this.viewinstanceof String ? (String) this.view :null);

??? }

??? /**

??? ?* Set a View object for this ModelAndView. Will override any

??? ?* pre-existing view name or View.

??? ?*/

??? publicvoid setView(View view) {

?????? this.view = view;

??? }

??? /**

??? ?* Return the View object, or<code>null</code> if we are using a view name

??? ?* to be resolved by the DispatcherServlet via a ViewResolver.

??? ?*/

??? public View getView() {

?????? return (this.viewinstanceof View ? (View) this.view :null);

??? }

??? /**

??? ?* Indicate whether or not this<code>ModelAndView</code> has a view, either

??? ?* as a view name or as a direct{@link View} instance.

??? ?*/

??? publicboolean hasView() {

?????? return (this.view != null);

??? }

??? /**

??? ?* Return whether we use a view reference, i.e.<code>true</code>

??? ?* if the view has been specified via a name to be resolved by the

??? ?* DispatcherServlet via a ViewResolver.

??? ?*/

??? publicboolean isReference() {

?????? return (this.viewinstanceof String);

??? }

??? /**

??? ?* Return the model map. May return<code>null</code>.

??? ?* Called by DispatcherServlet for evaluation of the model.

??? ?*/

??? protected Map<String, Object> getModelInternal() {

?????? returnthis.model;

??? }

??? /**

??? ?* Return the underlying <code>ModelMap</code> instance (never<code>null</code>).

??? ?*/

??? public ModelMap getModelMap() {

?????? if (this.model == null) {

?????????? this.model =new ModelMap();

?????? }

?????? returnthis.model;

??? }

??? /**

??? ?* Return the model map. Never returns<code>null</code>.

??? ?* To be called by application code for modifying the model.

??? ?*/

??? public Map<String, Object> getModel() {

?????? return getModelMap();

??? }

??? /**

??? ?* Add an attribute to the model.

??? ?* @param attributeName name of the object to add to the model

??? ?* @param attributeValue object to add to the model (never<code>null</code>)

??? ?* @see ModelMap#addAttribute(String, Object)

??? ?* @see #getModelMap()

??? ?*/

??? publicModelAndView addObject(String attributeName, Object attributeValue) {

?????? getModelMap().addAttribute(attributeName, attributeValue);

?????? returnthis;

??? }

??? /**

??? ?* Add an attribute to the model using parameter name generation.

??? ?* @param attributeValue the object to add to the model (never<code>null</code>)

??? ?* @see ModelMap#addAttribute(Object)

??? ?* @see #getModelMap()

??? ?*/

??? publicModelAndView addObject(Object attributeValue) {

?????? getModelMap().addAttribute(attributeValue);

?????? returnthis;

??? }

??? /**

??? ?* Add all attributes contained in the provided Map to the model.

??? ?* @param modelMap a Map of attributeName-> attributeValue pairs

??? ?* @see ModelMap#addAllAttributes(Map)

??? ?* @see #getModelMap()

??? ?*/

??? publicModelAndView addAllObjects(Map<String, ?> modelMap) {

?????? getModelMap().addAllAttributes(modelMap);

?????? returnthis;

??? }

??? /**

??? ?* Clear the state of this ModelAndView object.

??? ?* The object will be empty afterwards.

??? ?* <p>Can be used to suppress rendering of a given ModelAndView object

??? ?* in the <code>postHandle</code> method of a HandlerInterceptor.

??? ?* @see #isEmpty()

??? ?* @see HandlerInterceptor#postHandle

??? ?*/

??? publicvoid clear() {

?????? this.view =null;

?????? this.model =null;

?????? this.cleared =true;

??? }

??? /**

??? ?* Return whether this ModelAndView object is empty,

??? ?* i.e. whether it does not hold any view and does not contain a model.

??? ?*/

??? publicboolean isEmpty() {

?????? return (this.view == null && CollectionUtils.isEmpty(this.model));

??? }

??? /**

??? ?* Return whether this ModelAndView object is empty as a result of a call to{@link #clear}

??? ?* i.e. whether it does not hold any view and does not contain a model.

??? ?* <p>Returns <code>false</code> if any additional state was added to the instance

??? ?* <strong>after</strong> the call to{@link #clear}.

??? ?* @see #clear()

??? ?*/

??? publicboolean wasCleared() {

?????? return (this.cleared && isEmpty());

??? }

??? /**

??? ?* Return diagnostic information about this model and view.

??? ?*/

??? @Override

??? public String toString() {

??? ??? StringBuilder sb = new StringBuilder("ModelAndView: ");

?????? if (isReference()) {

?????????? sb.append("reference to view with name '").append(this.view).append("'");

?????? }

?????? else {

?????????? sb.append("materialized View is [").append(this.view).append(']');

?????? }

?????? sb.append("; model is ").append(this.model);

?????? return sb.toString();

??? }

}

測試代碼如下：

package com.sxt.web;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.servlet.ModelAndView;

import org.springframework.web.servlet.mvc.multiaction.MultiActionController;

import com.sxt.po.User;

@Controller

@RequestMapping("/user.do")

publicclass UserControllerextends MultiActionController?{

???

??? @RequestMapping(params="method=reg")

??? public ModelAndView reg(String uname){

?????? ModelAndView mv = new ModelAndView();

?????? mv.setViewName("index");

//???? mv.setView(new RedirectView("index"));

??????

?????? User u = new User();

?????? u.setUname("高淇");

?????? mv.addObject(u);?? //查看源代碼，得知，直接放入對象。屬性名為”首字母小寫的類名”。一般建議手動增加屬性名稱。

?????? mv.addObject("a","aaaa");

?????? returnmv;

??? }

}

<%@ page language="java"import="java.util.*"pageEncoding="gbk"%>

<%@ taglib prefix="c"uri="http://java.sun.com/jsp/jstl/core"%>

<!DOCTYPEHTMLPUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

? <head>

? </head>

? <body>

??? ?? <h1>${requestScope.a}</h1>

??? ?? <h1>${requestScope.user.uname}</h1>

? </body>

</html>

地址欄輸入：http://localhost:8080/springmvc03/user.do?method=reg

結果為：

基于spring 3.0mvc 框架的文件上傳實現

1. spring使用了apache-commons下得上傳組件，因此，我們需要引入兩個jar包：

1.?????? apache-commons-fileupload.jar

2.?????? apache-commons-io.jar

2.? 在springmvc-servlet.xml配置文件中，增加CommonsMultipartResoler配置：

<beanid="multipartResolver"?

??? class="org.springframework.web.multipart.commons.CommonsMultipartResolver">?

??? <propertyname="defaultEncoding"value="gbk"/>?

??? <propertyname="maxInMemorySize"value="10240"/>?

??? <propertyname="uploadTempDir"value="/upload/"/>?

??? <propertyname="maxUploadSize"value="-1"/>?

</bean>

3.? 建立upload.jsp頁面，內容如下：

????????

<%@ page language="java"import="java.util.*"pageEncoding="gbk"%>

<!DOCTYPEHTMLPUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

??? <head>

?????? <title>測試springmvc中上傳的實現</title>

??? </head>

??? <body>

<formaction="upload.do"?method="post"enctype="multipart/form-data">

?????????? <inputtype="text"name="name"/>

?????????? <inputtype="file"name="file"/>

?????????? <inputtype="submit"/>

?????? </form>

??? </body>

</html>

4. 建立控制器，代碼如下：

????????

package com.sxt.web;

import java.io.File;

import java.util.Date;

import javax.servlet.ServletContext;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.context.ServletContextAware;

import org.springframework.web.multipart.commons.CommonsMultipartFile;

@Controller

public class FileUploadController implements ServletContextAware {

???????? private ServletContext servletContext;

????????

???????? @Override

???????? public void setServletContext(ServletContext context) {

?????????????????? this.servletContext? = context;

???????? }

????????

???????? @RequestMapping(value="/upload.do", method = RequestMethod.POST)

???????? public String handleUploadData(String name,@RequestParam("file")[微軟用戶2]?CommonsMultipartFile file){

?????????????????? if (!file.isEmpty()) {

??????????????????????????? ?? String path = this.servletContext.getRealPath("/tmp/");? //獲取本地存儲路徑

??????????????????????????? ?? System.out.println(path);

??????????????????????????? ?? String fileName = file.getOriginalFilename();

??????????????????????????? ?? String fileType = fileName.substring(fileName.lastIndexOf("."));

??????????????????????????? ?? System.out.println(fileType);

??????????????????????????? ?? File file2 = new File(path,new Date().getTime() + fileType); //新建一個文件

??????????????????????????? ?? try {

???????????????????????????????????? ??? file.getFileItem().write(file2); //將上傳的文件寫入新建的文件中

??????????????????????????? ? ?} catch (Exception e) {

???????????????????????????????????? ??? e.printStackTrace();

??????????????????????????? ?? }

??????????????????????????? ?? return "redirect:upload_ok.jsp";

??????????????????????????? }else{

???????????????????????????????????? return "redirect:upload_error.jsp";

??????????????????????????? }

???????? }

}

5. 建立upload_ok.jsp頁面

<%@ page language="java"import="java.util.*"pageEncoding="gbk"%>

<!DOCTYPEHTMLPUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

? <head>

? </head>

? <body>

??? ?? <h1>上傳成功！</h1>

? </body>

</html>

6. 建立upload_error.jsp頁面

? <%@pagelanguage="java"import="java.util.*"pageEncoding="gbk"%>

<!DOCTYPEHTMLPUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

? <head>

? </head>

? <body>

??? ?? <h1>上傳失敗！</h1>

? </body>

</html>

7.?????? 發布項目，運行測試：http://localhost:8080/springmvc03/upload.jsp

?? 進入項目發布后的目錄，發現文件上傳成功：

處理ajax請求

spring使用了jackson類庫，幫助我們在java對象和json、xml數據之間的互相轉換。他可以將控制器返回的對象直接轉換成json數據，供客戶端使用。客戶端也可以傳送json數據到服務器進行直接轉換。使用步驟如下：

1.? 項目中需要引入如下兩個jar包：

???????? ???????? jackson-core-asl-1.7.2jar

?????????????????? jackson-mapper-asl-1.7.2jar

2.? spring配置文件中修改：

???????????<mvc:annotation-driven/>?

???

??? ? <beanclass="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">?

??????? <propertyname="cacheSeconds"value="0"/>?

??????? <propertyname="messageConverters">?

??????????? <list>?

??????????????? <beanclass="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"></bean>?

??????????? </list>?

??????? </property>

??? </bean>?

3.?????? 客戶端代碼a.jsp如下：

<%@pagelanguage="java"import="java.util.*"pageEncoding="gbk"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPEHTMLPUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

? <head>

??? <basehref="<%=basePath%>">

???

??? <title>My JSP 'index.jsp' starting page</title>

??? <metahttp-equiv="pragma"content="no-cache">

??? <metahttp-equiv="cache-control"content="no-cache">

??? <metahttp-equiv="expires"content="0">???

??? <metahttp-equiv="keywords"content="keyword1,keyword2,keyword3">

??? <metahttp-equiv="description"content="This is my page">

??? <script>

?????? function createAjaxObj(){

?????????? var req;

?????????? if(window.XMLHttpRequest){

????????????? req = new XMLHttpRequest();

??? ?????? }else{

????????????? req = new ActiveXObject("Msxml2.XMLHTTP");?//ie

?????????? }

?????????? return req;

?????? }

??????

?????? function sendAjaxReq(){

?????????? var req = createAjaxObj();

?????????? req.open("get","myajax.do?method=test2&uname=張三");

?????????? req.setRequestHeader("accept","application/json");

?????? ??? req.onreadystatechange? =function(){

????????????? eval("var result="+req.responseText);

????????????? document.getElementById("div1").innerHTML=result[0].uname;

?????????? }

?????????? req.send(null);

?????? }

??? </script>

? </head>

? <body>

??? <ahref="javascript:void(0);"onclick="sendAjaxReq();">測試</a>

??? <divid="div1"></div>

? </body>

</html>

4.?????? 服務器端代碼如下：

????????

package com.sxt.web;

import java.io.UnsupportedEncodingException;

import java.util.ArrayList;

import java.util.List;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestBody;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.ResponseBody;

import com.sxt.po.User;

@Controller

@RequestMapping("myajax.do")

public class MyAjaxController {

????????

???????? @RequestMapping(params="method=test1",method=RequestMethod.GET)

???????? public @ResponseBody List<User> test1(String uname) throws Exception{

?????????????????? String uname2 = new String(uname.getBytes("iso8859-1"),"gbk");

?????????????????? System.out.println(uname2);

?????????????????? System.out.println("MyAjaxController.test1()");

?????????????????? List<User> list = new ArrayList<User>();

?????????????????? list.add(new User("高淇","123"));

?????????????????? list.add(new User("馬士兵","456"));

??????????????????

?????????????????? return list;

???????? }

????????

}

5.?????? 測試。

a)???????? 啟動服務器。輸入：http://localhost:8080/springmvc03/a.jsp

Spring中的攔截器

定義spring攔截器兩種基本方式

1.?????? 實現接口：org.springframework.web.servlet.HandlerInterceptor。

接口中有如下方法需要重寫：

注意：參數中的Object handler是下一個攔截器。

a)???????? publicboolean preHandle
(HttpServletRequest request,HttpServletResponse response,
Object handler) throws Exception

該方法在action執行前執行，可以實現對數據的預處理，比如：編碼、安全控制等。

如果方法返回true，則繼續執行action。

b)???????? publicvoid postHandle
(HttpServletRequest request,HttpServletResponse response,
Object handler,?? ModelAndView modelAndView) throws Exception

該方法在action執行后，生成視圖前執行。在這里，我們有機會修改視圖層數據。

c)???????? publicvoid afterCompletion(HttpServletRequest request,HttpServletResponse response, Object handler, Exception ex)?? throws Exception

最后執行，通常用于釋放資源，處理異常。我們可以根據ex是否為空，來進行相關的異常處理。因為我們在平時處理異常時，都是從底層向上拋出異常，最后到了spring框架從而到了這個方法中。

2.?????? 繼承適配器：
org.springframework.web.servlet.handler.HandlerInterceptorAdapter

這個適配器實現了HandlerInterceptor接口。提供了這個接口中所有方法的空實現。

如下我們寫出兩個攔截器的示例代碼，僅供大家參考：

package com.sxt.interceptor;

importjavax.interceptor.Interceptors;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.HandlerInterceptor;

import org.springframework.web.servlet.ModelAndView;

publicclass MyInterceptorimplements HandlerInterceptor {

??? @Override

??? publicvoid afterCompletion(HttpServletRequest request,???HttpServletResponse response, Object handler, Exception ex)??? throws Exception {

?????? System.out.println("最后執行！！！一般用于釋放資源！！");

??????

??? }

??? @Override

??? publicvoid postHandle(HttpServletRequest request,HttpServletResponse response, Object handler,???ModelAndView modelAndView) throws Exception {

?????? System.out.println("Action執行之后，生成視圖之前執行！！");

??? }

??? @Override

??? publicboolean preHandle(HttpServletRequest request,HttpServletResponse response, Object handler)throws Exception {

?????? System.out.println("action之前執行！！！");

?????? returntrue;?//繼續執行action

??? }

}

package com.sxt.interceptor;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

publicclass MyInterceptor2extends HandlerInterceptorAdapter {

??? @Override

??? publicboolean preHandle(HttpServletRequest request,HttpServletResponse response, Object handler)throws Exception {

?????? System.out.println("MyInterceptor2.preHandle()");

?????? returntrue;?//繼續執行action

??? }

}

3.?????? XML中如何配置。如下為示例代碼：

???<mvc:interceptors>

?????? <beanclass="com.sxt.interceptor.MyInterceptor"></bean>

?????? <mvc:interceptor>

?????????? <mvc:mappingpath="/user.do"/>

??????????

?????????? <beanclass="com.sxt.interceptor.MyInterceptor2"></bean>

?????? </mvc:interceptor>

??? </mvc:interceptors>

總結

以上是生活随笔為你收集整理的springMVC3.0（文件上传，@RequestMapping加参数,@SessionAttributes,@ModelAttribute，转发，重定向，数值获取，传参，ajax,拦截器)的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。

上一篇：基于注解的Spring MVC整合Hib
下一篇： s3c2440移植MQTT