struts2字典的fileuploadinterceptor 拦截器 主要帮助获取上传文件的contenttype、filename、文件对象。如果开发人员在开发过程中使用。则需要设置set/get方法：
比如
setxxxcontenttype()
getxxxfilename()
getxxxcontenttype()
setxxxfilename()
getxxxfile()
setxxxfile()
其中,"xxx"为渲染器的name.
问题在这里
第一，如果除了contenttype/file/filename ，还需要其他的消息怎么办呢。拦截器就无能为力了。 这个可以忽略。
第二，平时在开发过程中，我们经常有动态添加附件功能。如果上传的附件同属于一类的话，还尚可。但是，如果一个页面中，需要上传多种类型的附件，而且每个附件类型动态增加的。拦截器就有点力不从心了。只能针对每个类型的附件，在action中写多个方法。
settype1file();
settype2file();
settype1contenttype();
settype2contenttype();
settype1filename();
settype2filename();
---------
问题在这里。如果我再增加一个类型呢？
在深层挖掘一下，如果我想做一个公共的文件上传处理类，怎么办。
本人研究了下自带的拦截器，在此基础上，通过自己的实践，提出自己的一个解决方案。
我通过map 来管理上传的文件列表。这样就不惧怕多类型文件上传，且可扩展性也提高了。
修正后的strut2 fileuploadinterceptor 如下
public string intercept(actioninvocation invocation) throws exception {
actioncontext ac = invocation.getinvocationcontext();
httpservletrequest request = (httpservletrequest) ac.get(servletactioncontext.http_request);
if (!(request instanceof multipartrequestwrapper)) {
if (log.isdebugenabled()) {
actionproxy proxy = invocation.getproxy();
log.debug(gettextmessage("struts.messages.bypass.request", new object[]{proxy.getnamespace(), proxy.getactionname()}, ac.getlocale()));
}
return invocation.invoke();
}
validationaware validation = null;
object action = invocation.getaction();
if (action instanceof validationaware) {
validation = (validationaware) action;
multipartrequestwrapper multiwrapper = (multipartrequestwrapper) request;
if (multiwrapper.haserrors()) {
for (string error : multiwrapper.geterrors()) {
if (validation != null) {
validation.addactionerror(error);
}
log.warn(error);
// bind allowed files
enumeration fileparameternames = multiwrapper.getfileparameternames();
map<string,list<map<string,object>>> fileparametermap = new hashmap<string,list<map<string,object>>>();//文件值对 //zhaogy
while (fileparameternames != null && fileparameternames.hasmoreelements()) {
// get the value of this input tag
string inputname = (string) fileparameternames.nextelement();
// get the content type
string[] contenttype = multiwrapper.getcontenttypes(inputname);
if (isnonempty(contenttype)) {
// get the name of the file from the input tag
string[] filename = multiwrapper.getfilenames(inputname);
if (isnonempty(filename)) {
// get a file object for the uploaded file
file[] files = multiwrapper.getfiles(inputname);
if (files != null && files.length > 0) {
list<file> acceptedfiles = new arraylist<file>(files.length);
list<string> acceptedcontenttypes = new arraylist<string>(files.length);
list<string> acceptedfilenames = new arraylist<string>(files.length);
list<string> rendernames = new arraylist<string>(files.length);
string contenttypename = inputname + "contenttype";
string filenamename = inputname + "filename";
for (int index = 0; index < files.length; index++) {
if (acceptfile(action, files[index], filename[index], contenttype[index], inputname, validation, ac.getlocale())) {
acceptedfiles.add(files[index]);
acceptedcontenttypes.add(contenttype[index]);
acceptedfilenames.add(filename[index]);
list<map<string, object>> vfl=null;
if(fileparametermap.containskey(inputname)){//是否已存在
vfl = fileparametermap.get(inputname);
}else{
vfl = new arraylist<map<string,object>>();
fileparametermap.put(inputname, vfl);
}
map<string, object> value = new hashmap<string,object>();
value.put("contenttype", contenttype[index]);
value.put("filename", filename[index]);
value.put("acceptedfile", files[index]);
vfl.add(value);
}
}
if (!acceptedfiles.isempty()) {
map<string, object> params = ac.getparameters();
params.put(inputname, acceptedfiles.toarray(new file[acceptedfiles.size()]));
params.put(contenttypename, acceptedcontenttypes.toarray(new string[acceptedcontenttypes.size()]));
params.put(filenamename, acceptedfilenames.toarray(new string[acceptedfilenames.size()]));
params.put("fileparametermap", fileparametermap);// zhaogy
}
} else {
log.warn(gettextmessage(action, "struts.messages.invalid.file", new object[]{inputname}, ac.getlocale()));
} else {
log.warn(gettextmessage(action, "struts.messages.invalid.content.type", new object[]{inputname}, ac.getlocale()));
// invoke action
string result = invocation.invoke();
// cleanup
fileparameternames = multiwrapper.getfileparameternames();
string inputvalue = (string) fileparameternames.nextelement();
file[] files = multiwrapper.getfiles(inputvalue);
for (file currentfile : files) {
if (log.isinfoenabled()) {
log.info(gettextmessage(action, "struts.messages.removing.file", new object[]{inputvalue, currentfile}, ac.getlocale()));
if ((currentfile != null) && currentfile.isfile()) {
if (currentfile.delete() == false) {
log.warn("resource leaking: could not remove uploaded file '" + currentfile.getcanonicalpath() + "'.");
return result;
}
测试代码：
/*
* $id: multiplefileuploadusinglistaction.java 660522 2008-05-27 14:08:00z jholmes $
*
* licensed to the apache software foundation (asf) under one
* or more contributor license agreements. see the notice file
* distributed with this work for additional information
* regarding copyright ownership. the asf licenses this file
* to you under the apache license, version 2.0 (the
* "license"); you may not use this file except in compliance
* with the license. you may obtain a copy of the license at
* http://www.apache.org/licenses/license-2.0
* unless required by applicable law or agreed to in writing,
* software distributed under the license is distributed on an
* "as is" basis, without warranties or conditions of any
* kind, either express or implied. see the license for the
* specific language governing permissions and limitations
* under the license.
*/
// start snippet: entire-file
package org.apache.struts2.showcase.fileupload;
import java.io.file;
import java.util.arraylist;
import java.util.iterator;
import java.util.list;
import java.util.map;
import com.opensymphony.xwork2.actionsupport;
/**
* showcase action - multiple file upload using list
* @version $date: 2008-05-27 16:08:00 +0200 (tue, 27 may 2008) $ $id: multiplefileuploadusinglistaction.java 660522 2008-05-27 14:08:00z jholmes $
public class multiplefileuploadusinglistaction extends actionsupport {
private list<file> uploads = new arraylist<file>();
private list<string> uploadfilenames = new arraylist<string>();
private list<string> uploadcontenttypes = new arraylist<string>();
public void setfileparametermap(
map<string, list<map<string, object>>> fileparametermap) {
this.fileparametermap = fileparametermap;
}
public list<file> getupload() {
return this.uploads;
}
public void setupload(list<file> uploads) {
this.uploads = uploads;
public list<string> getuploadfilename() {
return this.uploadfilenames;
public void setuploadfilename(list<string> uploadfilenames) {
this.uploadfilenames = uploadfilenames;
public list<string> getuploadcontenttype() {
return this.uploadcontenttypes;
public void setuploadcontenttype(list<string> contenttypes) {
this.uploadcontenttypes = contenttypes;
private map<string,list<map<string,object>>> fileparametermap;
public map<string, list<map<string, object>>> getfileparametermap() {
return fileparametermap;
public string upload() throws exception {
iterator<string> iter = this.fileparametermap.keyset().iterator();
while(iter.hasnext()){
string key = iter.next();
list<map<string, object>> vs = this.fileparametermap.get(key);
system.out.println("key========"+key);
for(map<string, object> v : vs){
object contenttype = v.get("contenttype");
object filename = v.get("filename");
object file = v.get("acceptedfile");
system.out.println("contenttype>>"+contenttype);
system.out.println("filename>>"+filename);
system.out.println("file>>"+file);
}
}
// system.out.println("\n\n upload1");
// system.out.println("files:");
// for (file u: uploads) {
// system.out.println("*** "+u+"\t"+u.length());
// }
// system.out.println("filenames:");
// for (string n: uploadfilenames) {
// system.out.println("*** "+n);
// system.out.println("content types:");
// for (string c: uploadcontenttypes) {
// system.out.println("*** "+c);
// system.out.println("\n\n");
return success;
}
// end snippet: entire-file
输出
key========upload2
contenttype>>application/octet-stream
filename>>xm_xvs.cfg
file>>d:\tomcat-6.0.20\work\catalina\localhost\struts2-showcase\upload_8c1aaae_1372ca9bef5__8000_00000011.tmp
contenttype>>text/html
filename>>login.html
file>>d:\tomcat-6.0.20\work\catalina\localhost\struts2-showcase\upload_8c1aaae_1372ca9bef5__8000_00000012.tmp
key========upload
contenttype>>text/plain
filename>>说明.txt
file>>d:\tomcat-6.0.20\work\catalina\localhost\struts2-showcase\upload_8c1aaae_1372ca9bef5__8000_00000008.tmp
contenttype>>application/vnd.openxmlformats-officedocument.wordprocessingml.document
filename>>孕妇饮食注意事项.docx
file>>d:\tomcat-6.0.20\work\catalina\localhost\struts2-showcase\upload_8c1aaae_1372ca9bef5__8000_00000009.tmp