[转载]Struts2文件上传实例

原文地址:Struts2文件上传实例作者:Valsun

struts2没有提供自己的请求解析器,也就是说,struts2不会自己去处理multipart/form-data的请求,它需要调用其他请求解析器,将HTTP请求中的表单域解析出来,但struts2在原有的上传解析器上作了进一步封装,更进一步简化了文件上传,Struts2的struts.properties配置文件中,配置struts2的上传文件解析器struts.multipart.parser=jakarta(srtuts2默认),也可以设置为常用的cos,pell等。

项目结构示意图:

[转载]Struts2文件上传实例

web.xml文件内容:

<?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">

[转载]Struts2文件上传实例

 <welcome-file-list>
  <welcome-file>index.jsp</welcome-file>
 </welcome-file-list>

</web-app>

 这里web.xml多配置了一个ActionContextCleanUp的配置,这个类是一个filter,他的作用是方便strut2与sitemesh整合,与文件上传本没有关系,但不加载这个filter,可能在上传中出现莫名的异常,加入后就稳定了,可能是strut2的bug吧。

index.jsp文件内容:

<%@page language="java" pageEncoding="GBK"%>
<
%@taglib prefix="s" uri="/struts-tags"%>
<
%@taglib prefix="c" uri="http://java.sun.com/jstl/core_rt"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
 <head>
  <meta http-equiv="pragma" content="no-cache">
  <meta http-equiv="cache-control" content="no-cache">
  <meta http-equiv="expires" content="0">
 </head>
 <body>
  ${requestScope.typeError}
  <form action="upload.action" method="post"
   enctype="multipart/form-data">
   <input type="text" name="title" />
   <br>
   <input type="file" name="upload" />
   <br>
   <input value="upload" type="submit" />
  </form>
 </body>
</html>

success.jsp文件内容:

<%@ page language="java" pageEncoding="GBK"%>
<
%@taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
 <head>
  <meta http-equiv="pragma" content="no-cache">
  <meta http-equiv="cache-control" content="no-cache">
  <meta http-equiv="expires" content="0">
 </head>

 <body>
  上传成功!
  <br>
  文件标题:
  <s:property value=" + title" />
  <br>
  文件为:
  <img src="<s:property value="'upload/' + uploadFileName"/>" />
  <br>
 </body>
</html>

struts.properties文件内容:

struts.locale=zh_CN
struts.i18n.encoding=GBK
struts.multipart.parser=jakarta

struts.xml文件内容:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "
http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
 <include file="struts-default.xml" />
    <constant name="struts.multipart.maxSize" value="20971520" />
 <constant name="struts.custom.i18n.resources"
  value="globalMessages" />
 <constant name="struts.i18n.encoding" value="GBK" />
 <package name="lee" extends="struts-default">
  <action name="upload" class="lee.UploadAction">
   <param name="allowTypes">
    image/pjpeg,image/bmp,image/jpg,image/png,image/gif,image/jpeg
   </param>
   <param name="savePath">/upload</param>
   <result>/success.jsp</result>
   <result name="input">/index.jsp</result>
  </action>
 </package>
</struts>

参看tomcat的web.xml中的mime:
<mime-mapping>
   <extension>gif</extension>
   <mime-type>image/gif</mime-type>
</mime-mapping>

UploadAction.java文件内容:

package lee;

import java.io.*;
import com.opensymphony.xwork2.ActionContext;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class UploadAction extends ActionSupport {
 private String title;
 private File upload;
 private String uploadContentType;
 private String uploadFileName;
 private String allowTypes;
 // 接受依赖注入的属性
 private String savePath;
 // 接受依赖注入的方法
 public void setSavePath(String value) {
  this.savePath = value;
 }
 private String getSavePath() throws Exception {
  return ServletActionContext.getServletContext().getRealPath(savePath);
 }
 public void setTitle(String title) {
  this.title = title;
 }
 public void setUpload(File upload) {
  this.upload = upload;
 }
 public void setUploadContentType(String uploadContentType) {
  this.uploadContentType = uploadContentType;
 }
 public void setUploadFileName(String uploadFileName) {
  this.uploadFileName = uploadFileName;
 }
 public String getTitle() {
  return (this.title);
 }
 public File getUpload() {
  return (this.upload);
 }
 public String getUploadContentType() {
  return (this.uploadContentType);
 }
 public String getUploadFileName() {
  return (this.uploadFileName);
 }
 @Override
 public String execute() throws Exception {
  System.out.println("开始上传单个文件---");
  System.out.println(getSavePath());
  System.out.println("==========" + getUploadFileName());
  System.out.println("==========" + getUploadContentType());
  System.out.println("==========" + getUpload());
  // 判断是否允许上传
  String filterResult = filterType(this.getAllowTypes().split(","));
  if (filterResult != null) {
   ActionContext.getContext().put("typeError","您要上传的文件类型不正确");
   return filterResult;
  }
  // 以服务器的文件保存地址和原文件名建立上传文件输出流
  FileOutputStream fos = new FileOutputStream(getSavePath() + "\"
    + getUploadFileName());
  FileInputStream fis = new FileInputStream(getUpload());
  byte[] buffer = new byte[1024];
  int len = 0;
  while ((len = fis.read(buffer)) > 0) {
   fos.write(buffer, 0, len);
  }
  return SUCCESS;
 }
 public String filterType(String[] types) {
  String fileType = this.getUploadContentType();
  for (String type : types) {
   if (type.equals(fileType)) {
    return null;
   }
  }
  return INPUT;
 }
 public String getAllowTypes() {
  return allowTypes;
 }
 public void setAllowTypes(String allowTypes) {
  this.allowTypes = allowTypes;
 }
}
Struts2针对表单中名为xxx的文件域,在对应的Action类中使用3个属性来封装该文件域信息:
1.类型为File的xxx属性:用来封装页面文件域对应的文件内容。
2.类型为String的xxxFileName属性:用来封装该文件域对应的文件的文件名。
3.类型为String的xxxContentType属性:用来封装该文件域应用的文件的文件类型。

以上程序调试通过!

posted @ 2014-07-22 16:42  刘竹青  阅读(90)  评论(0编辑  收藏  举报