Struts2下载文件的程序

Struts2下载文件的程序

在jsp里写：
   < a href = " download.action " > 点此下载文件 </ a >

在struts.xml中：
<? xml version = " 1.0 "  encoding = " UTF-8 " ?>
  <! DOCTYPE struts PUBLIC
     " -//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN "
     " http://struts.apache.org/dtds/struts-2.1.7.dtd " >
     < struts >
         < package  name = " mydown "   extends = " struts-default " >
             < action name = " download "   class = " com.yjw.web.DownAction " >
                 < param name = " id " > 1 </ param >
                 < result type = " stream " >
                
                
                     <!--  下载文件的mime类型  -->
                     < param name = " contentType " > $ {fileType} </ param >
                     <!--  下载文件的描述  -->
                     < param name = " contentDisposition " > attachment;filename = $ {fileName} </ param >
                     <!--  设置缓冲区大小  -->
                     < param name = " bufferSize " > 1024 </ param >
                     <!--  获得文件名的getxxx方法的名字 ，不包含get -->
                     < param name = " inputName " > inputStream </ param >
                 </ result >
             </ action >
         </ package >
     </ struts >
在action中的程序：
package  com.yjw.web;
import  java.io.File;
import  java.io.FileInputStream;
import  java.io.IOException;
import  java.io.InputStream;
import  org.apache.struts2.ServletActionContext;
import  com.opensymphony.xwork2.Action;
public   class  DownAction  implements   Action {
    private String fileName;
    private String id;
    private String fileType;
    public String execute() throws Exception {
        return "success";
    }
public InputStream  getInputStream() throws IOException{
    String path = ServletActionContext.getServletContext().getRealPath("/");
    if(id.equals("1")) {
        path = path + "download/less.pdf";
        fileName = "css.pdf";
        fileType = "application/pdf";
    } else {
        path = path + "download/data.xlsx";
        fileName = "data.xlsx";
        fileType = "application/vnd.ms-excel";
    }
        FileInputStream  stream = new  FileInputStream(new File(path));
    return stream;
    }
public String getFileName() {
    return fileName;
}
public void setFileName(String fileName) {
    this.fileName = fileName;
}
public String getId() {
    return id;
}
public void setId(String id) {
    this.id = id;
}
public String getFileType() {
    return fileType;
}
public void setFileType(String fileType) {
    this.fileType = fileType;
}
}