Java之网络编程（一）

package com.qianfeng.demo01;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;
/**
* InetSocketAddress:既封装了IP地址，主机名，又封装了端口号。
* */
public class InetSocketAddressDemo {

public static void main(String[] args) {
try {
InetSocketAddress socketAddress = new InetSocketAddress(InetAddress.getLocalHost(), 8888);
System.out.println("地址："+socketAddress.getAddress());
System.out.println("端口号："+socketAddress.getPort());
System.out.println("主机名："+socketAddress.getHostName());
System.out.println(socketAddress.toString());
} catch (UnknownHostException e) {
e.printStackTrace();
}
}
}

package com.qianfeng.demo01;
import java.net.InetAddress;
import java.net.UnknownHostException;
/**
* InetAddress :封装了IP地址和主机名，没有封装端口号
* */
public class InetAddressDemo {
public static void main(String[] args) throws UnknownHostException {
//		返回本机对象
InetAddress localHost = InetAddress.getLocalHost();
//		返回ip地址字符串形式
System.out.println(localHost.getHostAddress());
//		获取此 IP 地址的主机名。
System.out.println(localHost.getHostName());
byte[] bs = new byte[] {127,0,0, 1 };
System.out.println(InetAddress.getByAddress(bs));
//		在给定原始 IP 地址的情况下，返回 InetAddress 对象。
InetAddress address = InetAddress.getByName("127.0.0.1");
}
}

package com.qianfeng.demo01;

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

//URL :表示统一资源定位符，对于网络资源进行定位。
//     分为四部分： 协议名    主机名    端口号   资源文件内容
public class URLDemo01 {

public static void main(String[] args) {

try {
URL url1 = new URL("http://www.socs.uts.edu.au:80/MosaicDocs-old?url-primer.html");
System.out.println(url1.toString());
System.out.println("协议为："+url1.getProtocol());
System.out.println("主机名："+url1.getHost());
System.out.println("端口号："+url1.getPort());
System.out.println("资源文件名："+url1.getFile());
System.out.println("锚点:"+url1.getRef());  //#符号后面的内容
System.out.println("查询:"+url1.getQuery());  //?后面的内容

URL url2= new URL("http://www.baidu.com/picture/");
URL url3 = new URL(url2, "dog.png");
System.out.println(url3);
} catch (MalformedURLException e) {
e.printStackTrace();
}
}
}

package com.qianfeng.demo01;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
// 下载网页代码
public class URLDemo02 {

public static void main(String[] args) {
try {
URL url = new URL("http://society.firefox.sina.com/17/0822/03/DO4FU3KGQIL2B0PV.html");
InputStream is = url.openStream();

FileOutputStream fos = new FileOutputStream("news.html");

byte[]buf = new byte[1024];
int hasRead = 0;
while ((hasRead = is.read(buf))!=-1) {
fos.write(buf,0,hasRead);
}
fos.flush();

is.close();
fos.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}