package com.utils;

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

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

/**
 * @ClassName: FileUtils.java
 *
 * @Description: 文件下载
 *
 * @author GERRARD
 *
 * @date 2015年1月27日下午3:10:10
 * 
 */
public final class FileUtils {

	/**
	 * 文件下载
	 * 
	 * @param request
	 * @param response
	 * @param filePath
	 *            文件相对路径(带文件名和后缀)
	 * @throws IOException
	 */
	public static void downloadFile(HttpServletRequest request,HttpServletResponse response,String filePath) throws IOException {

        // 下载文件所在路径
        String basePath = request.getSession().getServletContext()
                .getRealPath("/");
        String downloadPath = basePath + filePath;

        File fn = new File(downloadPath);

        // 设置下载文件名
        String fileName = fn.getName();

        // 读取下载文件流
        InputStream inStream = new FileInputStream(downloadPath);

        // 设置输出的格式
        response.reset();
        response.setContentType("APPLICATION/OCTET-STREAM");
        fileName = URLEncoder.encode(fileName,"utf-8");
		response.setHeader("Content-Disposition","attachment; filename=\"" + fileName + "\"");
        // 循环取出流中的数据
        byte[] b = new byte[100];
        int len;
        try {
            while ((len = inStream.read(b)) > 0) {
                response.getOutputStream().write(b,len);
            }
            inStream.close();
            response.getOutputStream().close();
        } catch (IOException e) {
            e.printStackTrace();
            inStream.close();
            response.getOutputStream().close();
        }
    }
}

Action中调用

FileUtils.downloadFile(ServletActionContext.getRequest(),ServletActionContext.getResponse(),"/WEB-INF/model/template/"+ fileName);