URL下载网络资源

package edu.wtbu;

import java.net.MalformedURLException;
import java.net.URL;

public class Demo01 {
    //URL:统一资源定位符：定位互联网上的某一个资源
    //URL=协议://ip:port/项目名

    public static void main(String[] args) throws MalformedURLException {
        URL url = new URL("http://localhost:8080/helloworld/index.jsp?username=duhao&password=123456");
        System.out.println(url.getProtocol());//协议
        System.out.println(url.getHost());//ip
        System.out.println(url.getPort());//端口
        System.out.println(url.getPath());//文件
        System.out.println(url.getFile());//全路径
        System.out.println(url.getQuery());//参数

    }
}

package edu.wtbu;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
public class Demo02 {

    public static void main(String[] args) throws IOException {
        //1.下载地址
        URL url = new URL("http://localhost:8080/duhao/good.txt");

        //2.连接到这个资源 HTTP
        HttpURLConnection urlConnection = (HttpURLConnection)url.openConnection();

        InputStream is = urlConnection.getInputStream();
        FileOutputStream fos = new FileOutputStream("good.txt");

        byte[] bytes = new byte[1024];
        int len;
        while ((len=is.read())!=-1){
            fos.write(bytes,0,len);//写出这个数据
        }

        fos.close();
        is.close();
        urlConnection.disconnect();//断开连接
    }
}