springmvc工程文件上传下载

来源：互联网发布：c语言是否窗口编辑：程序博客网时间：2024/06/06 05:58

作为程序员,可能会在不经意间就写出来了一段让自己感到骄傲、欣喜、自豪的垃圾代码.

github已上传:https://github.com/kevindai007/springmvcTestProject

今天想新建一个springmvc工程实现上传下载功能,结果在Idea中折腾了半天才弄好,现在记录一下这填坑的过程

File—new—project
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然后一直点下一步直到Finish.这是idea会自动新建工程,看到Build success说明工程新建成功,如图

现在跑一下这个工程,看能否跑起来

启动tomcat,看到hello world界面说明工程新建成功

下面来配置springmvc,首先引入springmvc所需的jar包,在pom.xml中添加以下引用

<dependency>      <groupId>org.springframework</groupId>      <artifactId>spring-webmvc</artifactId>      <version>4.3.6.RELEASE</version></dependency><!--jsp要使用到的,开始没加,打开Jsp的时候报错 -->    <dependency>      <groupId>jstl</groupId>      <artifactId>jstl</artifactId>      <version>1.2</version>    </dependency>    <!--文件上传-->    <dependency>      <groupId>commons-io</groupId>      <artifactId>commons-io</artifactId>      <version>2.5</version>    </dependency>    <dependency>      <groupId>commons-fileupload</groupId>      <artifactId>commons-fileupload</artifactId>      <version>1.3.2</version>    </dependency>

然后在web.xml配置springmvc过滤;但在这之前咱们需要稍微更新一下web.xml的版本，可以支持更高级的一些语法，如下：

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd" ><web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"         version="3.1">  <display-name>Archetype Created Web Application</display-name></web-app>

然后添加springmvc的servlet

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd" ><web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"         version="3.1">  <display-name>Archetype Created Web Application</display-name>  <servlet>    <servlet-name>springmvc</servlet-name>    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>    <load-on-startup>1</load-on-startup>  </servlet>  <servlet-mapping>    <servlet-name>springmvc</servlet-name>    <url-pattern>/</url-pattern>  </servlet-mapping></web-app>

该servlet名为springmvc(名称可修改)，用于拦截请求(url-pattern为 / ，说明拦截所有请求)，并交由Spring MVC的后台控制器来处理。这一项配置是必须的。

为了能够处理中文的post请求，再配置一个encodingFilter，以避免post请求中文出现乱码情况(我开始忘记了,导致提交表单中文乱码):

<!-- 字符过滤 -->  <filter>    <filter-name>encodingFilter</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>encodingFilter</filter-name>    <url-pattern>/*</url-pattern>  </filter-mapping>

到这里web.xml的配置就完成了,下面咱们来一个总体预览

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd" ><web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"         version="3.1">  <display-name>Archetype Created Web Application</display-name>  <servlet>    <servlet-name>springmvc</servlet-name>    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>    <load-on-startup>1</load-on-startup>  </servlet>  <servlet-mapping>    <servlet-name>springmvc</servlet-name>    <url-pattern>/</url-pattern>  </servlet-mapping>  <!-- 字符过滤 -->  <filter>    <filter-name>encodingFilter</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>encodingFilter</filter-name>    <url-pattern>/*</url-pattern>  </filter-mapping></web-app>

在配置完web.xml后,需在web.xml同级目录下新建 springmvc-servlet.xml(-servlet前面是在servlet里面定义的servlet名):
这里写图片描述

要指定springmvc扫描路径时发现自己需要一个保存controller的包,在src\main下新建一个java文件夹由于存放java代码,这时发现不能在该文件夹下新建java文件,需要进行如下操作:
这里写图片描述
然后在java文件夹下新建com.kevindai.web包,并在该包下新建indexController.java文件,新建过程不赘述,代码如下

package com.kevindai.web;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;/** * Created by daiwenkai on 2017/2/7. */@Controllerpublic class IndexController {    @RequestMapping("/")    public String index(){        return "index";    }}

好的,回到springmvc-servlet.xml,进行相关配置.首先加入component-scan标签,指明controller所在的包,并扫描其中的注解(需要同时引入context命名空间,后面会给出)

<!--指明 controller 所在包，并扫描其中的注解--><context:component-scan base-package="com.kevindai.web"/>

然后开启注解

 <!-- 开启注解 --> <mvc:annotation-driven/>

然后配置视图解析器:

<!--ViewResolver 视图解析器-->    <!--用于支持Servlet、JSP视图解析-->    <bean id="jspViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>        <property name="prefix" value="/WEB-INF/jsp/"/>        <property name="suffix" value=".jsp"/>    </bean>

这里就是确定controller如何找到视图文件,这里需要详细的说明.在 controller 的一个方法中,返回的字符串定义了所需访问的jsp的名字（如上面的index）.在jspViewResolver中,有两个属性,一个是prefix,定义了所需访问的文件路径前缀,另一是suffix,表示要访问的文件的后缀,这里为 .jsp.那么,如果返回字符串是 xxx,SpringMVC就会找到 /WEB-INF/jsp/xxx.jsp 文件.
所以咱们还需要在WEB-INF下新建一个jsp文件夹,并在jsp文件夹下新建index.jsp文件(可以把工程中自带的index.jsp删除掉)

然后因为咱们要做上传功能所以还需要配置文件上传的解析器:

<!-- 上传文件 -->    <bean id="multipartResolver"          class="org.springframework.web.multipart.commons.CommonsMultipartResolver" >    </bean>

至此springmvc-servlet.xml的配置已经完成,来个总体预览

<?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.xsd                           http://www.springframework.org/schema/context                           http://www.springframework.org/schema/context/spring-context.xsd                           http://www.springframework.org/schema/mvc                           http://www.springframework.org/schema/mvc/spring-mvc.xsd">    <!--指明 controller 所在包，并扫描其中的注解-->    <context:component-scan base-package="com.kevindai.web"/>    <!-- 开启注解 -->    <mvc:annotation-driven/>    <!--ViewResolver 视图解析器-->    <!--用于支持Servlet、JSP视图解析-->    <bean id="jspViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>        <property name="prefix" value="/WEB-INF/jsp/"/>        <property name="suffix" value=".jsp"/>    </bean>    <!-- 上传文件 -->    <bean id="multipartResolver"          class="org.springframework.web.multipart.commons.CommonsMultipartResolver" >    </bean></beans>

下面修改WEB-INF/jsp/index.jsp页面,form表单中不要忘记加enctype=”multipart/form-data”,代码如下

<%--  Created by IntelliJ IDEA.  User: daiwenkai  Date: 2017/2/7  Time: 15:34  To change this template use File | Settings | File Templates.--%><%@ page contentType="text/html;charset=UTF-8" language="java" %><html><head>    <title>package apk</title></head><body><form action="/packagedApk" enctype="multipart/form-data" method="post">    <table>        <tr>            <td>渠 道 号:</td>            <td>                <input type="text" name="channelNum" id="channelNum">            </td>        </tr>        <tr>            <td>请选择文件:</td>            <td><input type="file" name="fileMsg" id="fileMsg"></td>        </tr>        <tr>            <td>                <input type="reset" value="重置">            </td>            <td>                <input type="submit" value="提交">            </td>        </tr>    </table></form></body></html>

在IndexController中添加packagedApk()方法,最终代码如下:

package com.kevindai.web;import com.kevindai.pojo.PackageApkPojo;import org.apache.commons.io.FileUtils;import org.springframework.http.HttpHeaders;import org.springframework.http.HttpStatus;import org.springframework.http.MediaType;import org.springframework.http.ResponseEntity;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;import java.io.*;/** * Created by daiwenkai on 2017/2/7. */@Controllerpublic class IndexController {    @RequestMapping("/")    public String index(){        return "index";    }    /**     * 方法写的很粗糙,就是接收上传文件并保存返回下载文件     * @param packageApkPojo     * @return     * @throws IOException     */    @RequestMapping(value = "/packagedApk")    @ResponseBody    public ResponseEntity<byte[]> packagedApk(PackageApkPojo packageApkPojo) throws IOException {        System.out.println(packageApkPojo.getChannelNum());        InputStream inputStream = packageApkPojo.getFileMsg().getInputStream();        String fileName = packageApkPojo.getFileMsg().getOriginalFilename();        OutputStream outputStream = new FileOutputStream("d:" + File.separator + fileName);        byte[] b = new byte[1024];        int c;        while((c = inputStream.read(b)) > 0){            outputStream.write(b);        }        inputStream.close();        outputStream.flush();        outputStream.close();        File file = new File("d:" + File.separator + fileName);        String dfileName = new String(fileName.getBytes("gb2312"), "iso8859-1");        HttpHeaders headers = new HttpHeaders();        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);        headers.setContentDispositionFormData("attachment", dfileName);        return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), headers, HttpStatus.CREATED);        //return "upload success";    }}

PackageApkPojo.java代码如下

package com.kevindai.pojo;import org.springframework.web.multipart.MultipartFile;/** * Created by daiwenkai on 2017/2/7. */public class PackageApkPojo {    private String channelNum;    private MultipartFile fileMsg;//与jsp中文件框id保持一致    public String getChannelNum() {        return channelNum;    }    public void setChannelNum(String channelNum) {        this.channelNum = channelNum;    }    public MultipartFile getFileMsg() {        return fileMsg;    }    public void setFileMsg(MultipartFile fileMsg) {        this.fileMsg = fileMsg;    }}

OK就这么简单的东西也折腾了一上午,填不完的坑啊,mdzz

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