javaweb文件下载

最近搞了一下struts文件上传下载了，一个是通过struts自带的类实现的下载方法，一个是通用的下载方法：

struts实现：

FileDownloadAction.java

package com.fro.action;

import java.io.FileInputStream;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;

import com.opensymphony.xwork2.ActionSupport;

public class FileDownloadAction extends ActionSupport implements ServletRequestAware, ServletResponseAware {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	private HttpServletRequest request;
	private HttpServletResponse response;
	private int number;
	private String fileName;
	private String contentType;

	public int getNumber() {
		return number;
	}

	public void setNumber(int number) {
		this.number = number;
	}

	public String getFileName() {
		return fileName;
	}

	public void setFileName(String fileName) throws UnsupportedEncodingException {
		this.fileName = fileName;
	}

	public HttpServletResponse getResponse() {
		return response;
	}

	public void setResponse(HttpServletResponse response) {
		this.response = response;
	}

	public String getContentType() {
		return contentType;
	}

	public void setContentType(String contentType) {
		this.contentType = contentType;
	}

	// 返回一个输入流，作为一个客户端来说是一个输入流，但对于服务器端是一个 输出流
	public InputStream getDownloadFile() {
		try {
			if (1 == number) {
				this.fileName = "使用说明书.doc";
				// 解决文件乱码问题
				if (request.getHeader("User-Agent").toLowerCase().indexOf("firefox") > 0) {
					fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1"); // firefox浏览器
				} else {
					fileName = URLEncoder.encode(fileName, "UTF-8");// IE浏览器
				}
				this.contentType = "application/msword";
				// 获取资源路径
				return ServletActionContext.getServletContext().getResourceAsStream("files/使用说明书.doc");
			} else if (2 == number) {
				this.fileName = "ModbusV2.0_down.mp4";
				// 解决文件乱码问题
				if (request.getHeader("User-Agent").toLowerCase().indexOf("firefox") > 0) {
					fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1"); // firefox浏览器
				} else {
					fileName = URLEncoder.encode(fileName, "UTF-8");// IE浏览器
				}
				this.contentType = "video/mp4";
				// 获取资源路径
				return ServletActionContext.getServletContext().getResourceAsStream("mediaelement/media/ModbusV2.0_down.mp4");
			}
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
		return null;
	}

	@Override
	public String execute() throws Exception {

		return SUCCESS;
	}

	@Override
	public void setServletResponse(HttpServletResponse response) {
		this.response = response;
	}

	@Override
	public void setServletRequest(HttpServletRequest request) {
		this.request = request;
	}
}

struts.xml文件配置：

　　　　<action name="FileDownload" class="com.fro.action.FileDownloadAction">
            <result name="success" type="stream">
                <param name="contentType">${contentType}</param>
                <param name="contentDisposition">attachment;fileName="${fileName}"</param>
                <param name="inputName">downloadFile</param>
                <param name="bufferSize">1024</param>
            </result>
        </action>

下面是通用的下载方法，不过我这里还是用struts实现的：

DdownloadAction.java

package com.fro.action;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URLEncoder;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;

import com.opensymphony.xwork2.ActionSupport;

public class DdownloadAction extends ActionSupport implements ServletRequestAware, ServletResponseAware {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	
	private String contentType;// 文件类型
	private String filename;// 指定下载后的文件名
	private HttpServletRequest request;
	private HttpServletResponse response;


	public InputStream getTargetFile() throws Exception {
		
		String realPath = request.getSession().getServletContext().getRealPath("/");
		String filePath = realPath + "/mediaelement/media/ModbusV2.0_down.mp4";
		System.out.println("filePath:" + filePath);
		File file = new File(filePath);
		
		response.setContentType("application/octet-stream; charset=UTF-8");
		String fileName = "ModbusV2.0_down.mp4";
		// 解决中文文件名乱码问题
		if (request.getHeader("User-Agent").toLowerCase().indexOf("firefox") > 0) {
			fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1"); // firefox浏览器
		} else {
			fileName = URLEncoder.encode(fileName, "UTF-8");// IE浏览器
		}
		response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
		
		InputStream in = new FileInputStream(file);
		OutputStream out = response.getOutputStream();
		byte[] data = new byte[1024];
		int len = 0;
		while ((len = in.read(data)) != -1) {
			out.write(data, 0, len);
		}
		out.flush();
		return null;
	}

	public String execute() throws Exception {
		
		return SUCCESS;

	}

	public String getContentType() {
		return contentType;
	}

	public void setContentType(String contentType) {
		this.contentType = contentType;
	}

	public String getFilename() {
		return filename;
	}

	public void setFilename(String filename) {
		this.filename = filename;
	}

	public HttpServletRequest getRequest() {
		return request;
	}

	public void setRequest(HttpServletRequest request) {
		this.request = request;
	}

	public HttpServletResponse getResponse() {
		return response;
	}

	public void setResponse(HttpServletResponse response) {
		this.response = response;
	}

	@Override
	public void setServletResponse(HttpServletResponse response) {
		response.setCharacterEncoding("utf-8");
		this.response = response;
	}

	@Override
	public void setServletRequest(HttpServletRequest request) {
		this.request = request;
	}
}

struts.xml文件配置：

　　　　<action name="download_*" class="com.fro.action.DdownloadAction" method="{1}">
            <result name="success" type="redirect">/index.jsp</result>
        </action>

下面是我的jsp文件：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>My JSP 'filedownload.jsp' starting page</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">


<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!-- 
        <link rel="stylesheet" type="text/css" href="styles.css"> 
        -->

</head>

<body>

	<h2>文件下载内容：</h2>
	<br /> 使用说明书.doc:
	<a href="FileDownload.action?number=1">点击下载</a>
	<br /> ModbusV2.0_down.mp4:
	<a href="FileDownload.action?number=2">点击下载</a>
	<br /> 使用说明书.doc:
	<a href="download_getTargetFile.action">点击下载</a>
	<br /> 使用说明书.doc:
	<a href="file_download.action">点击下载</a>


</body>
</html>

 其中解决了下载文件文件名中文乱码问题。

其他方式：

 //判断是否为火狐浏览器
      	String Agent = request.getHeader("User-Agent");
      	StringTokenizer st = new StringTokenizer(Agent,";");
      	st.nextToken();
      	//得到用户的浏览器类型
      	String userbrowser = st.nextToken();
      	//LOGGER.debug(userbrowser+"浏览器---------------------------");
      	//LOGGER.debug(userbrowser.trim().toLowerCase()+"浏览器类型---------------------------");
      	//LOGGER.debug(userbrowser.trim().toLowerCase().contains("wow64)")+"是否为火狐浏览器----------------------------");
      	if(userbrowser.toLowerCase().contains("wow64")){
      		response.setHeader("Content-Disposition", "attachment;filename="+ new String(fileName.getBytes("GB2312"),"ISO-8859-1"));
      	}else{
      		response.setHeader("content-disposition", "attachment;filename=" + URLEncoder.encode(realName, "UTF-8"));
      	}