FULL PRODUCT VERSION :
jdk1.6.0_01

A DESCRIPTION OF THE PROBLEM :
When I use "Negotiate"(Kerberos) authentication and I extend "java.net.Authenticator" class and redefine "getPasswordAuthentication()" method, I get NULL value from "getRequestingURL()" and "getRequestingHost()" method(these methods are defined in java.net.Authenticator class). When I use "Basic" authentication - all work properly(these methods return correct value).
I use HttpURLConnection class for both authentication schema.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package my.kerberos.test;

import java.net.Authenticator;
import java.net.PasswordAuthentication;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * This class is used as common point for standard java HttpURLConnection authentication.
 * It uses singleton pattern and do "Authenticator.setDefault(this)" in its constructor.
 * So it is default authenticator for all HttpURLConnection.
 *
 * @author Andrey Krasnov
 *
 */
public class BaseAuthenticator extends Authenticator {

	private Log log = LogFactory.getLog(this.getClass());
	
	private final static BaseAuthenticator instance = new BaseAuthenticator();
	static {
		Authenticator.setDefault(instance);
	}
	
	private Map<String, Account> urlMap = new HashMap<String, Account>();
	private Map<String, Account> hostMap = new HashMap<String, Account>();
	
	/**
	 * Register credentials for specified url
	 * @param url
	 * @param login
	 * @param password
	 * @return the previous value associated with key, or null if there was no mapping for key.
	 * (A null return can also indicate that the map previously associated null with key,
	 * if the implementation supports null values.)
	 */
	public static synchronized Account registerUrl(String url, String login, String password){
		if(url == null || login == null || password == null){
			throw new IllegalArgumentException("All parameters should be specified");
		}
		return instance.urlMap.put(url, new Account(login, password));
	}
	
	/**
	 * Register credentials for specified host
	 * @param host
	 * @param login
	 * @param password
	 * @return the previous value associated with key, or null if there was no mapping for key.
	 * (A null return can also indicate that the map previously associated null with key,
	 * if the implementation supports null values.)
	 */
	public static synchronized Account registerHost(String host, String login, String password){
		if(host == null || login == null || password == null){
			throw new IllegalArgumentException("All parameters should be specified");
		}
		return instance.hostMap.put(host, new Account(login, password));
	}
	
	/**
	 * Clear all registered credentials
	 */
	public static synchronized void reset(){
		instance.urlMap.clear();
		instance.hostMap.clear();
	}
	
	protected PasswordAuthentication getPasswordAuthentication() {
		
		log.debug("Authentication schema for \""+getRequestingURL()+"\": " + getRequestingScheme());
		
		Account account = urlMap.get(getRequestingURL());
		if( account != null ){
			return new PasswordAuthentication(account.login, account.password);
		}
		else if( (account = hostMap.get(getRequestingHost())) != null ){
			return new PasswordAuthentication(account.login, account.password);
		}
		
		return null;
	}
	
	/**
	 * This class encapsulates pair with login and password
	 *	@author Andrey Krasnov
	 *
	 */
	private static class Account {
		public final String login;
		public final char[] password;
		
		public Account(String login, String password){
			this.login = login;
			this.password = password.toCharArray();
		}
		
		public String toString(){
			return "[login: "+login+", password: ******]";
		}
	}
	
}

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