[Java] 실습 (InetAddress)

package network;

import java.net.*;
import java.util.*;

//----------------------------------------------------------------------
// public class NetworkExam01
//----------------------------------------------------------------------
public class NetworkExam01 {
	
	//----------------------------------------------------------------------
	// public static void main(String[] args)
	//----------------------------------------------------------------------
	public static void main(String[] args) {
		
		InetAddress ip = null;
		InetAddress[] ipArr = null;
		
		try {
			ip = InetAddress.getByName("www.google.com");
			System.out.println("getHostName() => " + ip.getHostName());
			System.out.println("getHostAddress() => " + ip.getHostAddress());
			System.out.println("toString() => " + ip.toString());
			
			byte[] ipAddr = ip.getAddress();
			System.out.println("getAddress() => " + Arrays.toString(ipAddr));
			
			String result = "";
			for(int i = 0; i < ipAddr.length; i++) {
				result += (ipAddr[i] < 0) ? ipAddr[i] + 256 : ipAddr[i];
				result += ",";
			}
			System.out.println("getAddress()+256 => " + result);
			System.out.println();
			
		} catch (UnknownHostException e) {
			e.printStackTrace();
		}
		
		try {
			ip = InetAddress.getLocalHost();
			System.out.println("getHostName() => " + ip.getHostName());
			System.out.println("getHostAddress() => " + ip.getHostAddress());
			System.out.println();
		} catch (UnknownHostException e) {
			e.printStackTrace();
		}
		
		try {
			ipArr = InetAddress.getAllByName("www.naver.com");
			
			for(int i = 0; i < ipArr.length; i++) {
				System.out.println("ipArr[" + "] => " + ipArr[i]);
			}
		} catch (UnknownHostException e) {
			e.printStackTrace();
		}

	} // End - public static void main(String[] args)

} // End - public class NetworkExam01

실행 결과

package network;

import java.net.*;

//----------------------------------------------------------------------
// public class NetworkExam01
//----------------------------------------------------------------------
public class NetworkExam02 {
	
	//----------------------------------------------------------------------
	// public static void main(String[] args)
	//----------------------------------------------------------------------
	public static void main(String[] args) throws Exception {
		
		URL url = new URL("https://n.news.naver.com/article/659/0000005154?cds=news_media_pc&type=editn");

		System.out.println("url.getAuthority() : " + url.getAuthority());
		System.out.println("url.getContent() : " + url.getContent());
		System.out.println("url.getDefaultPort() : " + url.getDefaultPort());
		System.out.println("url.getPort() : " + url.getPort());
		System.out.println("url.getFile() : " + url.getFile());
		
		System.out.println("url.getHost() : " + url.getHost());
		System.out.println("url.getPath() : " + url.getPath());
		System.out.println("url.getProtocol() : " + url.getProtocol());
		System.out.println("url.getQuery() : " + url.getQuery());
		System.out.println("url.getRef() : " + url.getRef());
		
		System.out.println("url.getUserInfo() : " + url.getUserInfo());
		System.out.println("url.toExternalForm() : " + url.toExternalForm());
		System.out.println("url.toURI() : " + url.toURI());
		
		
		
	} // End - public static void main(String[] args)

} // End - public class NetworkExam02

실행 결과

package network;

import java.net.*;
import java.io.*; // input, output
//----------------------------------------------------------------------
//public class NetworkExam03
//----------------------------------------------------------------------
public class NetworkExam03 {
	
	//----------------------------------------------------------------------
	// public static void main(String[] args)
	//----------------------------------------------------------------------
	public static void main(String[] args) {
		// 읽어 들이는
		URL url = null;
		BufferedReader  input = null;
		
		String address = "https://comic.naver.com/index";
		String line = "";
		
		try {
			url = new URL(address);
			
			input = new BufferedReader(new InputStreamReader(url.openStream()));
			
			while((line = input.readLine()) != null) {
			System.out.println(line);
			}
			input.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
		

	} // End - public static void main(String[] args)

} // End - public class NetworkExam03

실행 결과

package network;

import java.net.*;
import java.io.*;

//----------------------------------------------------------------------
//public class NetworkExam04
//----------------------------------------------------------------------
public class NetworkExam04 {

	//----------------------------------------------------------------------
	// public static void main(String[] args)
	//----------------------------------------------------------------------
	public static void main(String[] args) {
		
		URL 				url = null;
		InputStream 		in = null;
		FileOutputStream 	out = null;
		
		String address = "https://comic.naver.com/index";
		int ch = 0;
		
		try {
			url = new URL(address);
			in = url.openStream();
			out = new FileOutputStream("webtoon.txt");
			
			while((ch = in.read()) != -1) {
				out.write(ch);
			}
			in.close();
			out.close();
		} catch (Exception e) {
			e.printStackTrace();
		}

	} // End - public static void main(String[] args)

} // End - public class NetworkExam04

실행 결과