文件下载工具类

import java.io.*;
import java.net.URL;
import java.net.URLConnection;
/**
 * 下载工具类
 */
public class DownUtil {

    public static void main(String[] args) throws IOException {
        download("图片访问地址","生成图片的名称","生成图片的路径");
        download("图片访问地址","生成图片的名称","生成图片的路径");
        download("图片访问地址","生成图片的名称","生成图片的路径");
    }
    public static void download(String urlStr,String filename,String savePath) throws IOException {

        URL url = new URL(urlStr);
        //打开url连接
        URLConnection connection = url.openConnection();
        //请求超时时间
        connection.setConnectTimeout(5000);
        //输入流
        InputStream in = connection.getInputStream();
        //缓冲数据
        byte [] bytes = new byte[1024];
        //数据长度
        int len;
        //文件
        File file = new File(savePath);
        if(!file.exists())
            file.mkdirs();
        OutputStream out  = new FileOutputStream(file.getPath()+"\\"+filename);
        //先读到bytes中
        while ((len=in.read(bytes))!=-1){
            //再从bytes中写入文件
            out.write(bytes,0,len);
        }
        //关闭IO
        out.close();
        in.close();
    }
}