一、url类
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;

public class StreamTest4 {

public static void main(String[] args) {
    InputStream inStream=null;
    OutputStream outStream=null;
    try {
         URL url=new URL("https://www.baidu.com");//windows系统,直接baidu后,直接右键-属性-复制url地址就可以
         //但是mac系统,就比较无语
         inStream=url.openStream();
         //查看 inStream指向对象的类型是什么?
         System.out.println(inStream.getClass());
         outStream=new FileOutputStream("/Users/hanzhao/Desktop/1.html");
         //windows系统,就随便保存为“d:\\1.png”就好,但是mac系统试了试就只能保存为.html格式
         IOUtils.copy(inStream, outStream);
         System.out.println("下载成功");

    } catch (MalformedURLException e) {
        // TODO Auto-generated catch block
        //e.printStackTrace();
        System.out.println("地址错误"+e.getMessage());
    } catch (IOException e) {
        // TODO Auto-generated catch block
        //e.printStackTrace();
        System.out.println("打开网页错误"+e.getMessage());
    }finally {
        IOUtils.closeQuietly(inStream);
        IOUtils.closeQuietly(outStream);
    }

}

}