Struts2使用注解实现文件的上传与下载（二）

1 下载链接

<s:a href="download.action?fileName=pdf.txt">txt</s:a>
 <s:a href="download.action?fileName=pdf.png">png</s:a>
 <s:a href="download.action?fileName=pdf.pdf">pdf</s:a>
 <s:a href="download.action?fileName=X9Demo.zip">zip</s:a>
 <s:a href="download.action?fileName=axis2.war">war</s:a>
 <s:a href="download.action?fileName=axiom-api-1.2.7.jar">axiom-api-1.2.7.jar</s:a>
 <s:a href="download.action?fileName=Wildlife.wmv">Wildlife.wmv</s:a>

 

2 下载action

package com.cyb.action;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;

import org.apache.commons.io.FileUtils;
import org.apache.struts2.ServletActionContext;
import org.apache.struts2.convention.annotation.Namespace;
import org.apache.struts2.convention.annotation.ParentPackage;
import org.apache.struts2.convention.annotation.Results;
import org.apache.struts2.convention.annotation.Result;

import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;
import com.opensymphony.xwork2.Validateable;
import com.opensymphony.xwork2.ValidationAwareSupport;

/**
 * 所下载文件相关的的几个属性:文件格式 contentType,
 * 获取文件名的方法inputName,
 * 文件内容（显示的）属性contentDisposition,
 * 限定下载文件 缓冲区的值bufferSize
 * */
@Namespace("")
@Results({ @Result(name = "success",
             type = "stream",
             params = { "contentType",
  "application/octet-stream;charset=utf-8", "inputName",
  "inputStream", "contentDisposition",
  "attachment;filename=\"${fileName}\"", "bufferSize", "4096" }) })
public class DownloadAction extends ActionSupport {

 private static final long serialVersionUID = 8784555891643520648L;
 private String STORAGEPATH = "\\upload\\pdf.txt";

 private String fileName  ;// 初始的通过param指定的文件名属性
 private String storageId;
 private String inputPath;// 指定要被下载的文件路径

 public String getFileName() {
  return fileName;
 }

 public void setFileName(String fileName) {
  this.STORAGEPATH = "\\upload\\"+fileName;
  this.fileName = fileName;
 }

 public void setInputPath(String inputPath) {
  this.inputPath = inputPath;
 }

 public String getStorageId() {
  return storageId;
 }

 public void setStorageId(String storageId) {
  this.storageId = storageId;
 }

 // 如果下载文件名为中文，进行字符编码转换
 public String getDownloadFileName() {
  String downloadFileName = fileName;

  try {
   downloadFileName = new String(downloadFileName.getBytes(),"utf-8");
  } catch (UnsupportedEncodingException e) {
   e.printStackTrace();
  }

  return downloadFileName;
 }

 public InputStream getInputStream() throws Exception {
  /**
   * 下载用的Action应该返回一个InputStream实例，
   * 该方法对应在result里的inputName属性值为targetFile
   **/
  String realPath=ServletActionContext.getServletContext().getRealPath("\\upload")+ "\\"+fileName;
  File file = new File(realPath);
  if(!file.exists()){
   System.out.println("文件不存在！");
  }else{
   System.out.println("文件存在！");
  }
  System.out.println(realPath);
  InputStream is = ServletActionContext.getServletContext().getResourceAsStream(
    STORAGEPATH);
  return is;
 }

 public String download() {
  System.out.println("sdfsdfsdfsdf");
  //this.getInputStream();
  return SUCCESS;
 }

}
3 web.xml的配置

  <filter>
  <filter-name>struts2</filter-name>
  <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
        <init-param>
            <param-name>actionPackages</param-name>
            <param-value>com.cyb.action</param-value>
        </init-param> 
 </filter>

 <filter>
        <filter-name>struts-cleanup</filter-name>
        <filter-class>
            org.apache.struts2.dispatcher.ActionContextCleanUp
        </filter-class>
    </filter>

 <filter-mapping>
        <filter-name>struts-cleanup</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

 <filter-mapping>
  <filter-name>struts2</filter-name>
  <url-pattern>/*</url-pattern>
 </filter-mapping>