spring mvc 文件上傳

??????????????????????????????????????????????????????????????????????????spring mvc 文件上傳??

一、單文件上傳

配置步驟：

步驟一、在配置文件中配置包掃描器（暫且這樣配，會出問題，我們下面說解決方案）

<?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:p="http://www.springframework.org/schema/p"xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd "><!--讓spring掃描包下所有的類，讓標注spring注解的類生效  --><context:component-scan base-package="cn.hmy.controller"/></beans>

步驟二，定制我們的文件上傳jsp頁面

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><base href="<%=basePath%>"><title>文件上傳</title></head><body><form action="${pageContext.request.contextPath }/list.do" method="post" enctype="multipart/form-data"><h1>文件上傳</h1>文件:<input type="file" name="fileUpLoad"/></br><input type="submit" value="上傳"/>         </form></body>
</html>

步驟三、書寫我們的處理器代碼

package cn.hmy.controller;import java.io.File;
import java.io.IOException;import javax.servlet.http.HttpSession;import org.springframework.stereotype.Controller;import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.validation.annotation.Validated;import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.ModelAndView;import cn.hmy.pojo.UserInfo;@Controller
public class MyController{//處理器方法@RequestMapping(value="/list.do")    public void doFirst(MultipartFile fileUpLoad,HttpSession session) throws Exception{//1.獲取文件名稱String filename = fileUpLoad.getOriginalFilename();//2.獲取文件的前半部分路徑String realPath = session.getServletContext().getRealPath("/images");//3.拼接成完整的路徑File file=new File(realPath,filename);//4.保存文件
         fileUpLoad.transferTo(file); }        
}

此時我們啟動服務器，進行代碼上傳，會報如下錯誤

解決方案：更改我們的spring-servlet.xml配置文件

<?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:p="http://www.springframework.org/schema/p"xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd "><!--讓spring掃描包下所有的類，讓標注spring注解的類生效  --><context:component-scan base-package="cn.hmy.controller"/>
<!--配置復雜類型表達解析器-->
     <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"></bean></beans>

啟動發現還是會報上述錯誤?

解決方案：配置注解驅動

<?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:p="http://www.springframework.org/schema/p"xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd "><!--讓spring掃描包下所有的類，讓標注spring注解的類生效  --><context:component-scan base-package="cn.hmy.controller"/>
     <!--配置復雜類型表達解析器--><bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"></bean>
<!--配置注解驅動-->
     <mvc:annotation-driven/>
</beans>

如果在上述配置文件中缺少復雜類型解析器，會報如下錯誤

在解決了以上錯誤后，我們會發現如果我們上傳的文件中含有中文?? 會出現亂碼現象

解決亂碼

解決方案我們暫且提供以下兩種方式

方案一、

方案二、在web.xml中配置

<filter><filter-name>characterEncoding</filter-name><filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class><init-param><param-name>encoding</param-name><param-value>utf-8</param-value></init-param><init-param><param-name>forceEncoding</param-name><param-value>true</param-value></init-param></filter><filter-mapping><filter-name>characterEncoding</filter-name><url-pattern>/*</url-pattern></filter-mapping>

如何控制文件上傳大小

在spring-servlet.xml中配置如下

maxUploadSize為上傳的總文件的大小 5M
maxInMemorySize為上傳的單個文件的大小 1M

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"><property name="defaultEncoding" value="utf-8"></property><property name="maxUploadSize" value="5000000"></property><property name="maxInMemorySize" value="1000000"></property></bean>

如果超出所限制的大小? 會報如下錯誤

控制文件上傳的類型（通過后綴名進行控制）在處理器中進行判定

例如只允許上傳.jpg?? .png?? .gif為后綴的文件

package cn.hmy.controller;import java.io.File;
import java.io.IOException;import javax.servlet.http.HttpSession;import org.springframework.stereotype.Controller;import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.validation.annotation.Validated;import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.ModelAndView;import cn.hmy.pojo.UserInfo;@Controller
public class MyController{//處理器方法@RequestMapping(value="/list.do")    public String doFirst(MultipartFile fileUpLoad,HttpSession session) throws Exception{//1.獲取文件名稱String filename = fileUpLoad.getOriginalFilename();//限定文件上傳的類型if(filename.endsWith("jpg")||filename.endsWith("png")||filename.endsWith("gif")){//2.獲取文件的前半部分路徑String realPath = session.getServletContext().getRealPath("/images");//3.拼接成完整的路徑File file=new File(realPath,filename);//4.保存文件
             fileUpLoad.transferTo(file); }else{System.out.println("不支持上傳文件的類型");}return "/list.jsp";}        
}

如何判斷用戶沒用選上傳文件

多文件上傳

步驟一、

spring-servlet.xml配置文件

<?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:p="http://www.springframework.org/schema/p"xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="
        http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd "><!--讓spring掃描包下所有的類，讓標注spring注解的類生效  --><context:component-scan base-package="cn.hmy.controller"/><bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"><property name="defaultEncoding" value="utf-8"></property><property name="maxUploadSize" value="5000000"></property><property name="maxInMemorySize" value="1000000"></property></bean><mvc:annotation-driven/>
</beans>

步驟二、準備多文件上傳的jsp頁面

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><base href="<%=basePath%>"><title>文件上傳</title></head><body><form action="${pageContext.request.contextPath }/list.do" method="post" enctype="multipart/form-data"><h1>文件上傳</h1>文件1:<input type="file" name="fileUpLoad"/></br>文件2:<input type="file" name="fileUpLoad"/></br>文件3:<input type="file" name="fileUpLoad"/></br><input type="submit" value="上傳"/>         </form></body>
</html>

步驟三、編寫處理器的代碼

 //多文件上傳@RequestMapping(value="/list.do")    public String doFirst2(@RequestParam MultipartFile[] fileUpLoad,HttpSession session) throws Exception{for (MultipartFile item : fileUpLoad) {//1.獲取文件名稱String filename = item.getOriginalFilename();//限定文件上傳的類型if(filename.endsWith("jpg")||filename.endsWith("png")||filename.endsWith("gif")){//2.獲取文件的前半部分路徑String realPath = session.getServletContext().getRealPath("/images");//3.拼接成完整的路徑File file=new File(realPath,filename);//4.保存文件
                 item.transferTo(file); }else{System.out.println("不支持上傳文件的類型");}}return "/list.jsp";}