[[oktatas:programozás:java|< Java]]

====== Java web ======

  * **Szerző:** Sallai András
  * Copyright (c) 2014, Sallai András
  * Licenc: [[https://creativecommons.org/licenses/by-sa/4.0/|CC BY-SA 4.0]]
  * Web: https://szit.hu


===== Webtartalom lekérése =====

<code java Program01.java>
import java.net.URL;
import java.net.URLConnection;
import java.net.MalformedURLException;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.io.IOException;

class Program01
{
	public static void main(String args[])
	{
		InputStreamReader stream = null;
		BufferedReader reader = null;
		try 
		{
			URL url = new URL("http://szit.hu");
			URLConnection con = url.openConnection();
			stream = new InputStreamReader(con.getInputStream());
			reader = new BufferedReader(stream);
			System.out.println(reader.readLine());
			System.out.println(reader.readLine());
		}catch(MalformedURLException e)
		{
			System.out.println("Hibás URL");	
		}catch(IOException e)
		{
			System.out.println("Hiba a kapcsolatban");
		}finally
		{
			try{
				reader.close();
				stream.close();
			}catch(IOException e){}
		}
		
	}
}
</code>

===== Kivétel szétválasztással =====

<code java Program01.java>
import java.net.URL;
import java.net.URLConnection;
import java.net.MalformedURLException;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.io.IOException;
 
class Program01 {

	InputStreamReader stream = null;
	BufferedReader reader = null;	

	public void getWebpage() {
		try {
			tryGetWebpage();
		}catch(MalformedURLException e)	{
			System.out.println("Hibás URL");	
		}catch(IOException e) {
			System.out.println("Hiba a kapcsolatban");
		}finally {
			try{
				reader.close();
				stream.close();
			}catch(IOException e){}
		}
			
			
	}

	public void tryGetWebpage() throws MalformedURLException,
			IOException {
		
		URL url = new URL("http://szit.hu");
		URLConnection con = url.openConnection();
		stream = new InputStreamReader(con.getInputStream());
		reader = new BufferedReader(stream);
		
		System.out.println(reader.readLine());
		System.out.println(reader.readLine());
		
	}
	
	public static void main(String args[]) 	{
		Program01 program01 = new Program01();
		program01.getWebpage();
	}
}

</code>


===== Egész weblap beolvasása =====

For ciklussal:
<code java>
for (String line = reader.readLine(); line != null; line = reader.readLine()) {
	System.out.println(line);
}
</code>

While ciklussal:
<code java>
String line = null;
while ( (line = reader.readLine()) != null ) {
	System.out.println(line);
}
</code>

<code java Program01.java>
import java.net.URL;
import java.net.URLConnection;
import java.net.MalformedURLException;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.io.IOException;
 
class Program01 {

	InputStreamReader stream = null;
	BufferedReader reader = null;	

	public void getWebpage() {
		try {
			tryGetWebpage();
		}catch(MalformedURLException e)	{
			System.out.println("Hibás URL");	
		}catch(IOException e) {
			System.out.println("Hiba a kapcsolatban");
		}finally {
			try{
				reader.close();
				stream.close();
			}catch(IOException e){}
		}
			
			
	}

	public void tryGetWebpage() throws MalformedURLException,
			IOException {
		
		URL url = new URL("http://szit.hu");
		URLConnection con = url.openConnection();
		stream = new InputStreamReader(con.getInputStream());
		reader = new BufferedReader(stream);
		
		System.out.println(reader.readLine());
		System.out.println(reader.readLine());
		
		for (String line = reader.readLine(); line != null; line = reader.readLine()) {
			System.out.println(line);
		}		
		
	}
	
	public static void main(String args[]) 	{
		Program01 program01 = new Program01();
		program01.getWebpage();
	}
}

</code>

===== Linkek =====

  * http://stackoverflow.com/questions/5939732/jeditorpane-is-removing-css-font-styles
  * http://kickjava.com/src/javax/swing/text/html/CSS.java.htm