java文件下载

package com.common.util;

import org.apache.log4j.Logger;

import javax.servlet.http.HttpServletResponse;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URLEncoder;
import java.util.Map;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public final class FileUtils {

    private static final Logger logger = Logger.getLogger(FileUtils.class);


    //文件下载
    public void downLoadFile(HttpServletResponse response,String path) throws Exception {
        logger.info("path:"+path);
        File f = new File(path);
        if (!f.exists()) {
            response.sendError(404, "File not found!");
            return;
        }
        String fileName = f.getName();
        fileName = new String(fileName.getBytes("UTF-8"), "ISO-8859-1");

        BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));
        byte[] buf = new byte[1024];
        int len = 0;
        response.reset();
        response.setContentType("application/x-msdownload");
        response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
        OutputStream out = response.getOutputStream();
        while ((len = br.read(buf)) > 0){
            out.write(buf, 0, len);
        }
        br.close();
        out.close();
    }


    //下载压缩包
    public static void downloadZipFileByInputStream(HttpServletResponse response, Map<String,InputStream> map, String zipName) throws Exception{
        response.setContentType("application/x-msdownload");
        response.setHeader("content-disposition", "attachment;filename="+ URLEncoder.encode(zipName, "utf-8"));

        ZipOutputStream zos = new ZipOutputStream(response.getOutputStream());
        BufferedOutputStream bos = new BufferedOutputStream(zos);
        for(Map.Entry<String, InputStream> entry : map.entrySet()){
            String fileName = entry.getKey();            //每个文件的文件名
            InputStream inputStream = entry.getValue();  //每个文件的输入流

            BufferedInputStream bis = new BufferedInputStream(inputStream);
            zos.putNextEntry(new ZipEntry(fileName));

            int len = 0;
            byte[] buf = new byte[10 * 1024];
            while( (len=bis.read(buf, 0, buf.length)) != -1){
                bos.write(buf, 0, len);
            }
            bis.close();
            bos.flush();
        }
        bos.close();
    }

    //下载压缩包
    public void downloadZipFileByByte(HttpServletResponse response, Map<String, byte[]> files, String zipName) throws Exception{
        response.setContentType("application/x-msdownload");
        response.setHeader("content-disposition", "attachment;filename="+URLEncoder.encode(zipName, "utf-8"));

        ZipOutputStream zos = new ZipOutputStream(response.getOutputStream());
        BufferedOutputStream bos = new BufferedOutputStream(zos);

        for(Map.Entry<String, byte[]> entry : files.entrySet()){
            String fileName = entry.getKey();   //每个文件的文件名
            byte[]    file = entry.getValue();  //每个文件的字节

            BufferedInputStream bis = new BufferedInputStream(new ByteArrayInputStream(file));
            zos.putNextEntry(new ZipEntry(fileName));

            int len = 0;
            byte[] buf = new byte[10 * 1024];
            while( (len=bis.read(buf, 0, buf.length)) != -1){
                bos.write(buf, 0, len);
            }
            bis.close();
            bos.flush();
        }
        bos.close();
    }
}