文件下载的两种方式

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（一）传统的下载方式

package com.ruide.action;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;

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

public class DownLoadAction extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        this.doPost(request, response);
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String filename=request.getParameter("filename");
        filename=new String(filename.getBytes("ISO-8859-1"),"UTF-8");

        String path=request.getRealPath("/files/");
        path=path+"/"+filename;
        filename=new String (filename.getBytes(),"ISO-8859-1");

        response.setHeader("Content-Disposition", "attachment;filename="+filename);
        //response.setContentType("application/x-download");
        response.setContentType("application/x-download");

        //下载
        FileInputStream in=new FileInputStream(path);//本机上的
        OutputStream out=response.getOutputStream();//网络流
        int a=-1;
        if((a=in.read())!=-1){
            out.write(a);
        }
        in.close();
        out.close();
    }

}

SmartUpload 对象方式下载

package com.ruide.action;

import java.io.IOException;

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

import com.jspsmart.upload.SmartUpload;
import com.jspsmart.upload.SmartUploadException;

public class DownLoad1Action extends HttpServlet {


    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        this.doPost(request, response);
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String filename=request.getParameter("filename");
        String path=request.getRealPath("/files/");
        filename=new String(filename.getBytes("ISO-8859-1"),"UTF-8");
        path=path+"/"+filename;

        SmartUpload smt=new SmartUpload();
        smt.setContentDisposition(null);
        smt.initialize(this.getServletConfig(),request,response);

        try {
            smt.downloadFile(path);
        } catch (SmartUploadException e) {
            e.printStackTrace();
        }

    }

}