关于struts2上次图片和html以外的文件问题

今天看了struts2权威指南 第六章上传文件

发现在上传gif或html等文件时候

action中的
uploadFileName
uploadContentType
是可以显示出来的。
一旦上传doc.xls.,ppt等就显示为null
不知道怎么解决，谢谢大家帮忙.

以下是struts2 配置

image/*,text/*,application/msword,application/ms-excel
/files
/succ.jsp
/file.jsp

以下是action
package struts2.test.action;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class UploadAction extends ActionSupport{

private static final long serialVersionUID = 1L;
private File upload;
private String uploadContentType;
private String savePath;
private String uploadFileName;
private String allowTypes;

@SuppressWarnings("deprecation")
public String getSavePath() {
    return ServletActionContext.getServletContext().getRealPath(savePath);
}
public void setSavePath(String savePath) {
    this.savePath = savePath;
}
public File getUpload() {
    return upload;
}
public void setUpload(File upload) {
    this.upload = upload;
}
public String getUploadContentType() {
    return uploadContentType;
}
public void setUploadContentType(String uploadContentType) {
    this.uploadContentType = uploadContentType;
}
public String getUploadFileName() {
    return uploadFileName;
}
public void setUploadFileName(String uploadFileName) {
    this.uploadFileName = upload.getName();
}
public String execute() throws IOException{
    String filterResult = filterType(getAllowTypes().split(","));
    if(filterResult != null){
        ActionContext.getContext().put("typeError", "您要上传的文件类型不正确");
        return filterResult;
    }else{
            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);
            }
            fos.close();
            fis.close();
            return SUCCESS;
        }
}
public String getAllowTypes() {
    return allowTypes;
}
public void setAllowTypes(String allowTypes) {
    this.allowTypes = allowTypes;
}

public String filterType(String[] types){
    System.out.println(getUploadContentType());
    String fileType = getUploadContentType();
    for(String type:types){
        if(type.equals(fileType)){
            return null;
        }
    }
    return INPUT;
}

}

jsp 页面

<%@ page language="java" contentType="text/html; charset=UTF-8"%>
<%@taglib prefix="s" uri ="/struts-tags"%>

文件上传


${typeError}

word,excel,flash应该是这几个类型:
1.application/vnd.ms-excel
2.application/vnd.ms-word
3.application/x-shockwave-flash