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从指定服务器路径下载文件

package com.xiaobu.util;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * @author xiaobu
 * @version JDK1.8.0_171
 * @date on  2019/4/6 22:19
 * @description V1.0
 */
public class DownloadFolder {


    public static void main(String[] args) {
        //http://www.cicicaseshop.com/images/upload/Image/cici2250/1.jpg
        String url = "http://www.cicicaseshop.com/images/upload/Image/cici2250/1.jpg";
        String fileName = url.substring(url.lastIndexOf("/"));
        System.out.println("fileName---->" + fileName);
        String filePath = "d:";
        File file = getFile(url, filePath + fileName, "GET");
        System.out.println(file);
    }

    public static File getFile(String url, String filePath, String method) {
        //创建不同的文件夹目录
        File file = new File(filePath);
        //判断文件夹是否存在
        if (!file.exists()) {
            //如果文件夹不存在,则创建新的的文件夹
            //file.mkdirs();
            //如果文件不存在,则创建新的的文件
            try {
                file.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        FileOutputStream fileOut = null;
        HttpURLConnection conn = null;
        InputStream inputStream = null;
        try {
            // 建立链接
            URL httpUrl = new URL(url);
            conn = (HttpURLConnection) httpUrl.openConnection();
            //以Post方式提交表单,默认get方式
            conn.setRequestMethod(method);
            conn.setDoInput(true);
            conn.setDoOutput(true);
            // post方式不能使用缓存
            conn.setUseCaches(false);
            //连接指定的资源
            conn.connect();
            //获取网络输入流
            inputStream = conn.getInputStream();
            BufferedInputStream bis = new BufferedInputStream(inputStream);
            //判断文件的保存路径后面是否以/结尾
            if (!filePath.endsWith("/")) {

                filePath += "/";

            }
            System.out.println(filePath);
            //写入到文件(注意文件保存路径的后面一定要加上文件的名称)
            //fileOut = new FileOutputStream(filePath+"db.xml");
            //写入到文件(已经加了文件名)
            fileOut = new FileOutputStream(filePath);
            BufferedOutputStream bos = new BufferedOutputStream(fileOut);

            byte[] buf = new byte[4096];
            int length = bis.read(buf);
            //保存文件
            while (length != -1) {
                bos.write(buf, 0, length);
                length = bis.read(buf);
            }
            bos.close();
            bis.close();
            conn.disconnect();
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("抛出异常!!");
        }

        return file;

    }




}