Thread: Which of the subclasses of IOException are more probably to be thrown?

I want throw (IOException) for this program. But I don’t know which of the subclasses of IOException are more likely to be thrown by this program. How should I identify?

import java.io.*;
import java.net.*;
import java.util.ArrayList;
 
public class SimpleSpider
{
	ArrayList<String> set = new ArrayList<String>();
 
	public void search(String host)
	{
		try
		{
			URL u = new URL(host);
 
			set.add(host);
 
			ArrayList<String> tags = Util.extractTags(u);
			for (int i = 0; i < tags.size(); i++)
			{
				String nexthost = Util.extractURL(tags.get(i));
				if (nexthost != null && !set.contains(nexthost))
				{
					System.out.println(nexthost);
					search(nexthost);
				}
			}
		}
		catch (IOException e) {}
	}
 
	public static void main (String[] args)
	{
		SimpleSpider spider = new SimpleSpider();
		spider.search("http://en.origami-club.com/");
	}
}

I read the API. I think the most likely to be thrown is : EOFException, InterruptedIOException, UnknownHostException, MalformedURLException... Is there other Exception that is very likely to occur?