java如何使用ftp下载远程服务器文件_Java

java使用ftp下载远程服务器文件

第一种方法

连接中带有账号密码直接远程下载：

    public result<?> download(){
		//进行下载文件---------------------------------开始
        //远程服务器下载地址
        string fileurl = "ftp://superadmin:superadmin123@192.168.1.8:8888/usr/mp4pt/rec/chn0/10110120011100/00001.mp4";
        //文件物理路径
        string realfilepath = "f:/rhsftdemo/00001.mp4";
        //本地中新建文件夹目录
        file file = new file("f:/rhsftdemo/");
        if (!file.exists()) {
            file.mkdirs();
        }
        log.info("存储路径realfilepath:" + realfilepath + "下载路径：" + fileurl);
        download(fileurl,realfilepath);
        return result.ok();
    }

    private static final int buffer_size = 4096;
    public void download(string ftpurl,string savepath){
        long starttime = system.currenttimemillis();
//        string ftpurl = "ftp://ftp.f-secure.com/misc/unixutil/skeysrcs.zip";
        string file = "";
        // name of the file which has to be download
        string host = ""; // ftp server
        string user = ""; // user name of the ftp server
        string pass = ""; // password of the ftp server
//        string savepath = "f:\\skeysrcs.zip";
        ftpurl = string.format(ftpurl, user, pass, host);
        system.out.println("connecting to ftp server");
        try {
            url url = new url(ftpurl);
            urlconnection conn = url.openconnection();
            inputstream inputstream = conn.getinputstream();
            long filesize = conn.getcontentlength();
            system.out.println("size of the file to download in kb is:-" + filesize / 1024);
            fileoutputstream outputstream = new fileoutputstream(savepath);
            byte[] buffer = new byte[buffer_size];
            int bytesread = -1;
            while ((bytesread = inputstream.read(buffer)) != -1) {
                outputstream.write(buffer, 0, bytesread);
            }
            long endtime = system.currenttimemillis();
            system.out.println("file downloaded");
            system.out.println("download time in sec. is:-" + (endtime - starttime) / 1000);
            outputstream.close();
            inputstream.close();
        } catch (ioexception ex) {
            ex.printstacktrace();
        }
    }

第二种方法

通过账号密码登录后进行下载：

   public result<?> download(){
        //进行下载文件---------------------------------开始
        //远程服务器下载地址
        string fileurl = "ftp://192.168.1.8:8888/usr/mp4pt/rec/chn0/20220420095100/00001.mp4";
        //本地文件物理路径
        string realfilepath = "f:/rhsftdemo/00001.mp4";
        //本地中新建文件夹目录
        file file = new file("f:/rhsftdemo/");
        if (!file.exists()) {
            file.mkdirs();
        }
        log.info("存储路径realfilepath:" + realfilepath + "下载路径：" + fileurl);
        boolean bb = retepasvfile(realfilepath,fileurl,"00001.mp4");
        return result.ok();
    }


/**
     * 本地保存
     *
     * @param localurl 本地文件物理路径
     * @param hosturl 远程服务器下载地址
     * @param filename 文件名称
     *
     * @return
     */
    public synchronized boolean retepasvfile(string localurl, string hosturl, string filename) {
        ftpclient ftp = new ftpclient();
        boolean re = false;
        try {
            log.info("本地存储路径==:" + localurl);
            file file = fileutil.getfile(localurl);
            ftp.setconnecttimeout(10000);
            ftp.setdatatimeout(10000);
            ftp.connect("192.168.1.8", 21);
            if (!org.springframework.util.stringutils.isempty("admin") && !org.springframework.util.stringutils.isempty("superadmin123") && "superadmin" != "null" && "superadmin123" != "null") {
                //这里输入账号密码
                ftp.login("superadmin", "superadmin123");
            } else {
                log.info("开始链接ftp:");
                ftp.login("anonymous", "anonymous");
            }

            //ftp.bin();
            //  string str=ftp.pwd();
            ftp.enterlocalpassivemode(); //被动模式
            ftp.setcontrolkeepalivetimeout(60);
            ftp.setfiletype(ftp.binary_file_type);
            boolean b = ftp.changeworkingdirectory(hosturl.substring(0, hosturl.lastindexof("/")));
            log.info("pwd：" + b + "---切换目录：" + hosturl.substring(0, hosturl.lastindexof("/")));
            long locationsize = file.length();//服务器上文件的大小
            if (b) {
                boolean res = false;
                res = ftp.retrievefile(filename, new fileoutputstream(file));
                if (res) {
                    //ftp.disconnect();
                    log.info("文件下载完成");
                    re = true;
                } else {
                    log.info("文件下载失败");
                    //ftp.disconnect();
                }
            }
        } catch (exception e) {
            e.getstacktrace();

            log.error("retepasvfilesamba:e=3" + e);
        } finally {
            try {
                ftp.disconnect();
            } catch (exception e) {
            }
        }
        return re;
    }