HttpURLConnection null pointer exception

[chop ficaro]

this code generally works (accesses thousands of urls successfully), but once in a while i get a null pointer exception on particular HttpURLConnections, and its always the same urls
for conciseness ive trunkated the code to only up to where the exception was thrown.

why could this possibly be happening?

//takes an array of urls as strings, makes the requests and sends the results into a specified folder

import java.net.*;
import java.io.*;
import javax.swing.*;
import java.awt.*;
import java.util.regex.Pattern;
import java.util.regex.Matcher;

public class URLArrayToFiles
{

	public static void main (String[] args) throws Exception
	{
		//enter urls here to test
		String test[] = {"http://www.google.com/images/nav_logo8.png","http://patiscool.000space.com/","http://www.google.com/intl/en_ALL/images/logo.gif","http://www.google.com/#hl=en&source=hp&q=unreal&aq=f&aqi=g10&aql=&oq=&gs_rfai=&fp=84c7fb41710deb10"};
		new URLArrayToFiles  ("run_from_main\\",test);
	}
	
	//first paramater saving directory, 2nd paramater array of urls as strings
	URLArrayToFiles (String dirNoSlashes, String[] inAddr) throws Exception
	{

		//make directories if not already exist
		String dirText = "text";
		String dirTarget = "target";
		(new File(dirNoSlashes + dirTarget + "\\")).mkdirs();
		(new File(dirNoSlashes + dirText + "\\")).mkdirs();
		(new File(dirNoSlashes + dirTarget + "\\stats\\")).mkdirs();
		(new File(dirNoSlashes + dirText + "\\stats\\")).mkdirs();
		BufferedWriter targetLog = new BufferedWriter(new FileWriter(dirNoSlashes + dirTarget + "\\" + "stats\\log.txt"));
		BufferedWriter textLog = new BufferedWriter(new FileWriter(dirNoSlashes + dirText + "\\" + "stats\\log.txt"));
		//loop encloses whole program, loops through array of addresses
		for (int i = 0; i < inAddr.length; i++)
		{
		
			//create prefix for file name for chronological order and for results that do not return a name
			java.text.DecimalFormat nft = new java.text.DecimalFormat("#0000.###");
			nft.setDecimalSeparatorAlwaysShown(false);
			System.out.println("result number: " + nft.format(i));	
		
			//try encloses whole loop, many io exceptions possible
			try
			{
				
				//connect
				URL u = new URL(inAddr[i]);
				HttpURLConnection uc = (HttpURLConnection)u.openConnection( );
				
				//get data for verbose output longest wait in program is here
				int code = uc.getResponseCode( );

java.lang.NullPointerException
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown So
urce)
        at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(Unknown So
urce)
        at java.net.HttpURLConnection.getResponseCode(Unknown Source)
        at URLArrayToFiles.<init>(URLArrayToFiles.java:51)
        at InputScreen.actionPerformed(InputScreen.java:189)
        at java.awt.Button.processActionEvent(Unknown Source)
        at java.awt.Button.processEvent(Unknown Source)
        at java.awt.Component.dispatchEventImpl(Unknown Source)
        at java.awt.Component.dispatchEvent(Unknown Source)
        at java.awt.EventQueue.dispatchEvent(Unknown Source)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
        at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
        at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
        at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
        at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.lang.NullPointerException
        at sun.net.www.ParseUtil.toURI(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Sour
ce)
        at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown So
urce)
        ... 14 more

[Rob Spoor]

Please CarefullyChooseOneForum. This question is completely not GUI related. I'm moving this thread to our sockets / Internet protocols forum.