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	/*
	* reserved comment block
	* DO NOT REMOVE OR ALTER!
	*/
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.sun.org.apache.xerces.internal.util;

	import java.io.IOException;
	import java.io.Serializable;
	import java.util.Objects;

	/**********************************************************************
	* A class to represent a Uniform Resource Identifier (URI). This class
	* is designed to handle the parsing of URIs and provide access to
	* the various components (scheme, host, port, userinfo, path, query
	* string and fragment) that may constitute a URI.
	* <p>
	* Parsing of a URI specification is done according to the URI
	* syntax described in
	* <a href="http://www.ietf.org/rfc/rfc2396.txt?number=2396">RFC 2396</a>,
	* and amended by
	* <a href="http://www.ietf.org/rfc/rfc2732.txt?number=2732">RFC 2732</a>.
	* <p>
	* Every absolute URI consists of a scheme, followed by a colon (':'),
	* followed by a scheme-specific part. For URIs that follow the
	* "generic URI" syntax, the scheme-specific part begins with two
	* slashes ("//") and may be followed by an authority segment (comprised
	* of user information, host, and port), path segment, query segment
	* and fragment. Note that RFC 2396 no longer specifies the use of the
	* parameters segment and excludes the "user:password" syntax as part of
	* the authority segment. If "user:password" appears in a URI, the entire
	* user/password string is stored as userinfo.
	* <p>
	* For URIs that do not follow the "generic URI" syntax (e.g. mailto),
	* the entire scheme-specific part is treated as the "path" portion
	* of the URI.
	* <p>
	* Note that, unlike the java.net.URL class, this class does not provide
	* any built-in network access functionality nor does it provide any
	* scheme-specific functionality (for example, it does not know a
	* default port for a specific scheme). Rather, it only knows the
	* grammar and basic set of operations that can be applied to a URI.
	*
	*
	**********************************************************************/
	public class URI implements Serializable {

	/*******************************************************************
	* MalformedURIExceptions are thrown in the process of building a URI
	* or setting fields on a URI when an operation would result in an
	* invalid URI specification.
	*
	********************************************************************/
	public static class MalformedURIException extends IOException {

	/** Serialization version. */
	static final long serialVersionUID = -6695054834342951930L;

	/******************************************************************
	* Constructs a <code>MalformedURIException</code> with no specified
	* detail message.
	******************************************************************/
	public MalformedURIException() {
	super();
	}

	/*****************************************************************
	* Constructs a <code>MalformedURIException</code> with the
	* specified detail message.
	*
	* @param p_msg the detail message.
	******************************************************************/
	public MalformedURIException(String p_msg) {
	super(p_msg);
	}
	}

	/** Serialization version. */
	static final long serialVersionUID = 1601921774685357214L;

	private static final byte [] fgLookupTable = new byte[128];

	/**
	* Character Classes
	*/

	/** reserved characters ;/?:@&=+$,[] */
	//RFC 2732 added '[' and ']' as reserved characters
	private static final int RESERVED_CHARACTERS = 0x01;

	/** URI punctuation mark characters: -_.!~*'() - these, combined with
	alphanumerics, constitute the "unreserved" characters */
	private static final int MARK_CHARACTERS = 0x02;

	/** scheme can be composed of alphanumerics and these characters: +-. */
	private static final int SCHEME_CHARACTERS = 0x04;

	/** userinfo can be composed of unreserved, escaped and these
	characters: ;:&=+$, */
	private static final int USERINFO_CHARACTERS = 0x08;

	/** ASCII letter characters */
	private static final int ASCII_ALPHA_CHARACTERS = 0x10;

	/** ASCII digit characters */
	private static final int ASCII_DIGIT_CHARACTERS = 0x20;

	/** ASCII hex characters */
	private static final int ASCII_HEX_CHARACTERS = 0x40;

	/** Path characters */
	private static final int PATH_CHARACTERS = 0x80;

	/** Mask for alpha-numeric characters */
	private static final int MASK_ALPHA_NUMERIC = ASCII_ALPHA_CHARACTERS \| ASCII_DIGIT_CHARACTERS;

	/** Mask for unreserved characters */
	private static final int MASK_UNRESERVED_MASK = MASK_ALPHA_NUMERIC \| MARK_CHARACTERS;

	/** Mask for URI allowable characters except for % */
	private static final int MASK_URI_CHARACTER = MASK_UNRESERVED_MASK \| RESERVED_CHARACTERS;

	/** Mask for scheme characters */
	private static final int MASK_SCHEME_CHARACTER = MASK_ALPHA_NUMERIC \| SCHEME_CHARACTERS;

	/** Mask for userinfo characters */
	private static final int MASK_USERINFO_CHARACTER = MASK_UNRESERVED_MASK \| USERINFO_CHARACTERS;

	/** Mask for path characters */
	private static final int MASK_PATH_CHARACTER = MASK_UNRESERVED_MASK \| PATH_CHARACTERS;

	static {
	// Add ASCII Digits and ASCII Hex Numbers
	for (int i = '0'; i <= '9'; ++i) {
	fgLookupTable[i] \|= ASCII_DIGIT_CHARACTERS \| ASCII_HEX_CHARACTERS;
	}

	// Add ASCII Letters and ASCII Hex Numbers
	for (int i = 'A'; i <= 'F'; ++i) {
	fgLookupTable[i] \|= ASCII_ALPHA_CHARACTERS \| ASCII_HEX_CHARACTERS;
	fgLookupTable[i+0x00000020] \|= ASCII_ALPHA_CHARACTERS \| ASCII_HEX_CHARACTERS;
	}

	// Add ASCII Letters
	for (int i = 'G'; i <= 'Z'; ++i) {
	fgLookupTable[i] \|= ASCII_ALPHA_CHARACTERS;
	fgLookupTable[i+0x00000020] \|= ASCII_ALPHA_CHARACTERS;
	}

	// Add Reserved Characters
	fgLookupTable[';'] \|= RESERVED_CHARACTERS;
	fgLookupTable['/'] \|= RESERVED_CHARACTERS;
	fgLookupTable['?'] \|= RESERVED_CHARACTERS;
	fgLookupTable[':'] \|= RESERVED_CHARACTERS;
	fgLookupTable['@'] \|= RESERVED_CHARACTERS;
	fgLookupTable['&'] \|= RESERVED_CHARACTERS;
	fgLookupTable['='] \|= RESERVED_CHARACTERS;
	fgLookupTable['+'] \|= RESERVED_CHARACTERS;
	fgLookupTable['$'] \|= RESERVED_CHARACTERS;
	fgLookupTable[','] \|= RESERVED_CHARACTERS;
	fgLookupTable['['] \|= RESERVED_CHARACTERS;
	fgLookupTable[']'] \|= RESERVED_CHARACTERS;

	// Add Mark Characters
	fgLookupTable['-'] \|= MARK_CHARACTERS;
	fgLookupTable['_'] \|= MARK_CHARACTERS;
	fgLookupTable['.'] \|= MARK_CHARACTERS;
	fgLookupTable['!'] \|= MARK_CHARACTERS;
	fgLookupTable['~'] \|= MARK_CHARACTERS;
	fgLookupTable['*'] \|= MARK_CHARACTERS;
	fgLookupTable['\''] \|= MARK_CHARACTERS;
	fgLookupTable['('] \|= MARK_CHARACTERS;
	fgLookupTable[')'] \|= MARK_CHARACTERS;

	// Add Scheme Characters
	fgLookupTable['+'] \|= SCHEME_CHARACTERS;
	fgLookupTable['-'] \|= SCHEME_CHARACTERS;
	fgLookupTable['.'] \|= SCHEME_CHARACTERS;

	// Add Userinfo Characters
	fgLookupTable[';'] \|= USERINFO_CHARACTERS;
	fgLookupTable[':'] \|= USERINFO_CHARACTERS;
	fgLookupTable['&'] \|= USERINFO_CHARACTERS;
	fgLookupTable['='] \|= USERINFO_CHARACTERS;
	fgLookupTable['+'] \|= USERINFO_CHARACTERS;
	fgLookupTable['$'] \|= USERINFO_CHARACTERS;
	fgLookupTable[','] \|= USERINFO_CHARACTERS;

	// Add Path Characters
	fgLookupTable[';'] \|= PATH_CHARACTERS;
	fgLookupTable['/'] \|= PATH_CHARACTERS;
	fgLookupTable[':'] \|= PATH_CHARACTERS;
	fgLookupTable['@'] \|= PATH_CHARACTERS;
	fgLookupTable['&'] \|= PATH_CHARACTERS;
	fgLookupTable['='] \|= PATH_CHARACTERS;
	fgLookupTable['+'] \|= PATH_CHARACTERS;
	fgLookupTable['$'] \|= PATH_CHARACTERS;
	fgLookupTable[','] \|= PATH_CHARACTERS;
	}

	/** Stores the scheme (usually the protocol) for this URI. */
	private String m_scheme = null;

	/** If specified, stores the userinfo for this URI; otherwise null */
	private String m_userinfo = null;

	/** If specified, stores the host for this URI; otherwise null */
	private String m_host = null;

	/** If specified, stores the port for this URI; otherwise -1 */
	private int m_port = -1;

	/** If specified, stores the registry based authority for this URI; otherwise -1 */
	private String m_regAuthority = null;

	/** If specified, stores the path for this URI; otherwise null */
	private String m_path = null;

	/** If specified, stores the query string for this URI; otherwise
	null. */
	private String m_queryString = null;

	/** If specified, stores the fragment for this URI; otherwise null */
	private String m_fragment = null;

	private static boolean DEBUG = false;

	/**
	* Construct a new and uninitialized URI.
	*/
	public URI() {
	}

	/**
	* Construct a new URI from another URI. All fields for this URI are
	* set equal to the fields of the URI passed in.
	*
	* @param p_other the URI to copy (cannot be null)
	*/
	public URI(URI p_other) {
	initialize(p_other);
	}

	/**
	* Construct a new URI from a URI specification string. If the
	* specification follows the "generic URI" syntax, (two slashes
	* following the first colon), the specification will be parsed
	* accordingly - setting the scheme, userinfo, host,port, path, query
	* string and fragment fields as necessary. If the specification does
	* not follow the "generic URI" syntax, the specification is parsed
	* into a scheme and scheme-specific part (stored as the path) only.
	*
	* @param p_uriSpec the URI specification string (cannot be null or
	* empty)
	*
	* @exception MalformedURIException if p_uriSpec violates any syntax
	* rules
	*/
	public URI(String p_uriSpec) throws MalformedURIException {
	this((URI)null, p_uriSpec);
	}

	/**
	* Construct a new URI from a URI specification string. If the
	* specification follows the "generic URI" syntax, (two slashes
	* following the first colon), the specification will be parsed
	* accordingly - setting the scheme, userinfo, host,port, path, query
	* string and fragment fields as necessary. If the specification does
	* not follow the "generic URI" syntax, the specification is parsed
	* into a scheme and scheme-specific part (stored as the path) only.
	* Construct a relative URI if boolean is assigned to "true"
	* and p_uriSpec is not valid absolute URI, instead of throwing an exception.
	*
	* @param p_uriSpec the URI specification string (cannot be null or
	* empty)
	* @param allowNonAbsoluteURI true to permit non-absolute URIs,
	* false otherwise.
	*
	* @exception MalformedURIException if p_uriSpec violates any syntax
	* rules
	*/
	public URI(String p_uriSpec, boolean allowNonAbsoluteURI) throws MalformedURIException {
	this((URI)null, p_uriSpec, allowNonAbsoluteURI);
	}

	/**
	* Construct a new URI from a base URI and a URI specification string.
	* The URI specification string may be a relative URI.
	*
	* @param p_base the base URI (cannot be null if p_uriSpec is null or
	* empty)
	* @param p_uriSpec the URI specification string (cannot be null or
	* empty if p_base is null)
	*
	* @exception MalformedURIException if p_uriSpec violates any syntax
	* rules
	*/
	public URI(URI p_base, String p_uriSpec) throws MalformedURIException {
	initialize(p_base, p_uriSpec);
	}

	/**
	* Construct a new URI from a base URI and a URI specification string.
	* The URI specification string may be a relative URI.
	* Construct a relative URI if boolean is assigned to "true"
	* and p_uriSpec is not valid absolute URI and p_base is null
	* instead of throwing an exception.
	*
	* @param p_base the base URI (cannot be null if p_uriSpec is null or
	* empty)
	* @param p_uriSpec the URI specification string (cannot be null or
	* empty if p_base is null)
	* @param allowNonAbsoluteURI true to permit non-absolute URIs,
	* false otherwise.
	*
	* @exception MalformedURIException if p_uriSpec violates any syntax
	* rules
	*/
	public URI(URI p_base, String p_uriSpec, boolean allowNonAbsoluteURI) throws MalformedURIException {
	initialize(p_base, p_uriSpec, allowNonAbsoluteURI);
	}

	/**
	* Construct a new URI that does not follow the generic URI syntax.
	* Only the scheme and scheme-specific part (stored as the path) are
	* initialized.
	*
	* @param p_scheme the URI scheme (cannot be null or empty)
	* @param p_schemeSpecificPart the scheme-specific part (cannot be
	* null or empty)
	*
	* @exception MalformedURIException if p_scheme violates any
	* syntax rules
	*/
	public URI(String p_scheme, String p_schemeSpecificPart)
	throws MalformedURIException {
	if (p_scheme == null \|\| p_scheme.trim().length() == 0) {
	throw new MalformedURIException(
	"Cannot construct URI with null/empty scheme!");
	}
	if (p_schemeSpecificPart == null \|\|
	p_schemeSpecificPart.trim().length() == 0) {
	throw new MalformedURIException(
	"Cannot construct URI with null/empty scheme-specific part!");
	}
	setScheme(p_scheme);
	setPath(p_schemeSpecificPart);
	}

	/**
	* Construct a new URI that follows the generic URI syntax from its
	* component parts. Each component is validated for syntax and some
	* basic semantic checks are performed as well. See the individual
	* setter methods for specifics.
	*
	* @param p_scheme the URI scheme (cannot be null or empty)
	* @param p_host the hostname, IPv4 address or IPv6 reference for the URI
	* @param p_path the URI path - if the path contains '?' or '#',
	* then the query string and/or fragment will be
	* set from the path; however, if the query and
	* fragment are specified both in the path and as
	* separate parameters, an exception is thrown
	* @param p_queryString the URI query string (cannot be specified
	* if path is null)
	* @param p_fragment the URI fragment (cannot be specified if path
	* is null)
	*
	* @exception MalformedURIException if any of the parameters violates
	* syntax rules or semantic rules
	*/
	public URI(String p_scheme, String p_host, String p_path,
	String p_queryString, String p_fragment)
	throws MalformedURIException {
	this(p_scheme, null, p_host, -1, p_path, p_queryString, p_fragment);
	}

	/**
	* Construct a new URI that follows the generic URI syntax from its
	* component parts. Each component is validated for syntax and some
	* basic semantic checks are performed as well. See the individual
	* setter methods for specifics.
	*
	* @param p_scheme the URI scheme (cannot be null or empty)
	* @param p_userinfo the URI userinfo (cannot be specified if host
	* is null)
	* @param p_host the hostname, IPv4 address or IPv6 reference for the URI
	* @param p_port the URI port (may be -1 for "unspecified"; cannot
	* be specified if host is null)
	* @param p_path the URI path - if the path contains '?' or '#',
	* then the query string and/or fragment will be
	* set from the path; however, if the query and
	* fragment are specified both in the path and as
	* separate parameters, an exception is thrown
	* @param p_queryString the URI query string (cannot be specified
	* if path is null)
	* @param p_fragment the URI fragment (cannot be specified if path
	* is null)
	*
	* @exception MalformedURIException if any of the parameters violates
	* syntax rules or semantic rules
	*/
	public URI(String p_scheme, String p_userinfo,
	String p_host, int p_port, String p_path,
	String p_queryString, String p_fragment)
	throws MalformedURIException {
	if (p_scheme == null \|\| p_scheme.trim().length() == 0) {
	throw new MalformedURIException("Scheme is required!");
	}

	if (p_host == null) {
	if (p_userinfo != null) {
	throw new MalformedURIException(
	"Userinfo may not be specified if host is not specified!");
	}
	if (p_port != -1) {
	throw new MalformedURIException(
	"Port may not be specified if host is not specified!");
	}
	}

	if (p_path != null) {
	if (p_path.indexOf('?') != -1 && p_queryString != null) {
	throw new MalformedURIException(
	"Query string cannot be specified in path and query string!");
	}

	if (p_path.indexOf('#') != -1 && p_fragment != null) {
	throw new MalformedURIException(
	"Fragment cannot be specified in both the path and fragment!");
	}
	}

	setScheme(p_scheme);
	setHost(p_host);
	setPort(p_port);
	setUserinfo(p_userinfo);
	setPath(p_path);
	setQueryString(p_queryString);
	setFragment(p_fragment);
	}

	/**
	* Initialize all fields of this URI from another URI.
	*
	* @param p_other the URI to copy (cannot be null)
	*/
	private void initialize(URI p_other) {
	m_scheme = p_other.getScheme();
	m_userinfo = p_other.getUserinfo();
	m_host = p_other.getHost();
	m_port = p_other.getPort();
	m_regAuthority = p_other.getRegBasedAuthority();
	m_path = p_other.getPath();
	m_queryString = p_other.getQueryString();
	m_fragment = p_other.getFragment();
	}

	/**
	* Initializes this URI from a base URI and a URI specification string.
	* See RFC 2396 Section 4 and Appendix B for specifications on parsing
	* the URI and Section 5 for specifications on resolving relative URIs
	* and relative paths.
	*
	* @param p_base the base URI (may be null if p_uriSpec is an absolute
	* URI)
	* @param p_uriSpec the URI spec string which may be an absolute or
	* relative URI (can only be null/empty if p_base
	* is not null)
	* @param allowNonAbsoluteURI true to permit non-absolute URIs,
	* in case of relative URI, false otherwise.
	*
	* @exception MalformedURIException if p_base is null and p_uriSpec
	* is not an absolute URI or if
	* p_uriSpec violates syntax rules
	*/
	private void initialize(URI p_base, String p_uriSpec, boolean allowNonAbsoluteURI)
	throws MalformedURIException {

	String uriSpec = p_uriSpec;
	int uriSpecLen = (uriSpec != null) ? uriSpec.length() : 0;

	if (p_base == null && uriSpecLen == 0) {
	if (allowNonAbsoluteURI) {
	m_path = "";
	return;
	}
	throw new MalformedURIException("Cannot initialize URI with empty parameters.");
	}

	// just make a copy of the base if spec is empty
	if (uriSpecLen == 0) {
	initialize(p_base);
	return;
	}

	int index = 0;

	// Check for scheme, which must be before '/', '?' or '#'.
	int colonIdx = uriSpec.indexOf(':');
	if (colonIdx != -1) {
	final int searchFrom = colonIdx - 1;
	// search backwards starting from character before ':'.
	int slashIdx = uriSpec.lastIndexOf('/', searchFrom);
	int queryIdx = uriSpec.lastIndexOf('?', searchFrom);
	int fragmentIdx = uriSpec.lastIndexOf('#', searchFrom);

	if (colonIdx == 0 \|\| slashIdx != -1 \|\|
	queryIdx != -1 \|\| fragmentIdx != -1) {
	// A standalone base is a valid URI according to spec
	if (colonIdx == 0 \|\| (p_base == null && fragmentIdx != 0 && !allowNonAbsoluteURI)) {
	throw new MalformedURIException("No scheme found in URI.");
	}
	}
	else {
	initializeScheme(uriSpec);
	index = m_scheme.length()+1;

	// Neither 'scheme:' or 'scheme:#fragment' are valid URIs.
	if (colonIdx == uriSpecLen - 1 \|\| uriSpec.charAt(colonIdx+1) == '#') {
	throw new MalformedURIException("Scheme specific part cannot be empty.");
	}
	}
	}
	else if (p_base == null && uriSpec.indexOf('#') != 0 && !allowNonAbsoluteURI) {
	throw new MalformedURIException("No scheme found in URI.");
	}

	// Two slashes means we may have authority, but definitely means we're either
	// matching net_path or abs_path. These two productions are ambiguous in that
	// every net_path (except those containing an IPv6Reference) is an abs_path.
	// RFC 2396 resolves this ambiguity by applying a greedy left most matching rule.
	// Try matching net_path first, and if that fails we don't have authority so
	// then attempt to match abs_path.
	//
	// net_path = "//" authority [ abs_path ]
	// abs_path = "/" path_segments
	if (((index+1) < uriSpecLen) &&
	(uriSpec.charAt(index) == '/' && uriSpec.charAt(index+1) == '/')) {
	index += 2;
	int startPos = index;

	// Authority will be everything up to path, query or fragment
	char testChar = '\0';
	while (index < uriSpecLen) {
	testChar = uriSpec.charAt(index);
	if (testChar == '/' \|\| testChar == '?' \|\| testChar == '#') {
	break;
	}
	index++;
	}

	// Attempt to parse authority. If the section is an empty string
	// this is a valid server based authority, so set the host to this
	// value.
	if (index > startPos) {
	// If we didn't find authority we need to back up. Attempt to
	// match against abs_path next.
	if (!initializeAuthority(uriSpec.substring(startPos, index))) {
	index = startPos - 2;
	}
	}
	else {
	m_host = "";
	}
	}

	initializePath(uriSpec, index);

	// Resolve relative URI to base URI - see RFC 2396 Section 5.2
	// In some cases, it might make more sense to throw an exception
	// (when scheme is specified is the string spec and the base URI
	// is also specified, for example), but we're just following the
	// RFC specifications
	if (p_base != null) {
	absolutize(p_base);
	}
	}

	/**
	* Initializes this URI from a base URI and a URI specification string.
	* See RFC 2396 Section 4 and Appendix B for specifications on parsing
	* the URI and Section 5 for specifications on resolving relative URIs
	* and relative paths.
	*
	* @param p_base the base URI (may be null if p_uriSpec is an absolute
	* URI)
	* @param p_uriSpec the URI spec string which may be an absolute or
	* relative URI (can only be null/empty if p_base
	* is not null)
	*
	* @exception MalformedURIException if p_base is null and p_uriSpec
	* is not an absolute URI or if
	* p_uriSpec violates syntax rules
	*/
	private void initialize(URI p_base, String p_uriSpec)
	throws MalformedURIException {

	String uriSpec = p_uriSpec;
	int uriSpecLen = (uriSpec != null) ? uriSpec.length() : 0;

	if (p_base == null && uriSpecLen == 0) {
	throw new MalformedURIException(
	"Cannot initialize URI with empty parameters.");
	}

	// just make a copy of the base if spec is empty
	if (uriSpecLen == 0) {
	initialize(p_base);
	return;
	}

	int index = 0;

	// Check for scheme, which must be before '/', '?' or '#'.
	int colonIdx = uriSpec.indexOf(':');
	if (colonIdx != -1) {
	final int searchFrom = colonIdx - 1;
	// search backwards starting from character before ':'.
	int slashIdx = uriSpec.lastIndexOf('/', searchFrom);
	int queryIdx = uriSpec.lastIndexOf('?', searchFrom);
	int fragmentIdx = uriSpec.lastIndexOf('#', searchFrom);

	if (colonIdx == 0 \|\| slashIdx != -1 \|\|
	queryIdx != -1 \|\| fragmentIdx != -1) {
	// A standalone base is a valid URI according to spec
	if (colonIdx == 0 \|\| (p_base == null && fragmentIdx != 0)) {
	throw new MalformedURIException("No scheme found in URI.");
	}
	}
	else {
	initializeScheme(uriSpec);
	index = m_scheme.length()+1;

	// Neither 'scheme:' or 'scheme:#fragment' are valid URIs.
	if (colonIdx == uriSpecLen - 1 \|\| uriSpec.charAt(colonIdx+1) == '#') {
	throw new MalformedURIException("Scheme specific part cannot be empty.");
	}
	}
	}
	else if (p_base == null && uriSpec.indexOf('#') != 0) {
	throw new MalformedURIException("No scheme found in URI.");
	}

	// Two slashes means we may have authority, but definitely means we're either
	// matching net_path or abs_path. These two productions are ambiguous in that
	// every net_path (except those containing an IPv6Reference) is an abs_path.
	// RFC 2396 resolves this ambiguity by applying a greedy left most matching rule.
	// Try matching net_path first, and if that fails we don't have authority so
	// then attempt to match abs_path.
	//
	// net_path = "//" authority [ abs_path ]
	// abs_path = "/" path_segments
	if (((index+1) < uriSpecLen) &&
	(uriSpec.charAt(index) == '/' && uriSpec.charAt(index+1) == '/')) {
	index += 2;
	int startPos = index;

	// Authority will be everything up to path, query or fragment
	char testChar = '\0';
	while (index < uriSpecLen) {
	testChar = uriSpec.charAt(index);
	if (testChar == '/' \|\| testChar == '?' \|\| testChar == '#') {
	break;
	}
	index++;
	}

	// Attempt to parse authority. If the section is an empty string
	// this is a valid server based authority, so set the host to this
	// value.
	if (index > startPos) {
	// If we didn't find authority we need to back up. Attempt to
	// match against abs_path next.
	if (!initializeAuthority(uriSpec.substring(startPos, index))) {
	index = startPos - 2;
	}
	} else if (index < uriSpecLen) {
	//Same as java.net.URI:
	// DEVIATION: Allow empty authority prior to non-empty
	// path, query component or fragment identifier
	m_host = "";
	} else {
	throw new MalformedURIException("Expected authority.");
	}
	}

	initializePath(uriSpec, index);

	// Resolve relative URI to base URI - see RFC 2396 Section 5.2
	// In some cases, it might make more sense to throw an exception
	// (when scheme is specified is the string spec and the base URI
	// is also specified, for example), but we're just following the
	// RFC specifications
	if (p_base != null) {
	absolutize(p_base);
	}
	}

	/**
	* Absolutize URI with given base URI.
	*
	* @param p_base base URI for absolutization
	*/
	public void absolutize(URI p_base) {

	// check to see if this is the current doc - RFC 2396 5.2 #2
	// note that this is slightly different from the RFC spec in that
	// we don't include the check for query string being null
	// - this handles cases where the urispec is just a query
	// string or a fragment (e.g. "?y" or "#s") -
	// see <http://www.ics.uci.edu/~fielding/url/test1.html> which
	// identified this as a bug in the RFC
	if (m_path.length() == 0 && m_scheme == null &&
	m_host == null && m_regAuthority == null) {
	m_scheme = p_base.getScheme();
	m_userinfo = p_base.getUserinfo();
	m_host = p_base.getHost();
	m_port = p_base.getPort();
	m_regAuthority = p_base.getRegBasedAuthority();
	m_path = p_base.getPath();

	if (m_queryString == null) {
	m_queryString = p_base.getQueryString();

	if (m_fragment == null) {
	m_fragment = p_base.getFragment();
	}
	}
	return;
	}

	// check for scheme - RFC 2396 5.2 #3
	// if we found a scheme, it means absolute URI, so we're done
	if (m_scheme == null) {
	m_scheme = p_base.getScheme();
	}
	else {
	return;
	}

	// check for authority - RFC 2396 5.2 #4
	// if we found a host, then we've got a network path, so we're done
	if (m_host == null && m_regAuthority == null) {
	m_userinfo = p_base.getUserinfo();
	m_host = p_base.getHost();
	m_port = p_base.getPort();
	m_regAuthority = p_base.getRegBasedAuthority();
	}
	else {
	return;
	}

	// check for absolute path - RFC 2396 5.2 #5
	if (m_path.length() > 0 &&
	m_path.startsWith("/")) {
	return;
	}

	// if we get to this point, we need to resolve relative path
	// RFC 2396 5.2 #6
	String path = "";
	String basePath = p_base.getPath();

	// 6a - get all but the last segment of the base URI path
	if (basePath != null && basePath.length() > 0) {
	int lastSlash = basePath.lastIndexOf('/');
	if (lastSlash != -1) {
	path = basePath.substring(0, lastSlash+1);
	}
	}
	else if (m_path.length() > 0) {
	path = "/";
	}

	// 6b - append the relative URI path
	path = path.concat(m_path);

	// 6c - remove all "./" where "." is a complete path segment
	int index = -1;
	while ((index = path.indexOf("/./")) != -1) {
	path = path.substring(0, index+1).concat(path.substring(index+3));
	}

	// 6d - remove "." if path ends with "." as a complete path segment
	if (path.endsWith("/.")) {
	path = path.substring(0, path.length()-1);
	}

	// 6e - remove all "<segment>/../" where "<segment>" is a complete
	// path segment not equal to ".."
	index = 1;
	int segIndex = -1;
	String tempString = null;

	while ((index = path.indexOf("/../", index)) > 0) {
	tempString = path.substring(0, path.indexOf("/../"));
	segIndex = tempString.lastIndexOf('/');
	if (segIndex != -1) {
	if (!tempString.substring(segIndex).equals("..")) {
	path = path.substring(0, segIndex+1).concat(path.substring(index+4));
	index = segIndex;
	}
	else {
	index += 4;
	}
	}
	else {
	index += 4;
	}
	}

	// 6f - remove ending "<segment>/.." where "<segment>" is a
	// complete path segment
	if (path.endsWith("/..")) {
	tempString = path.substring(0, path.length()-3);
	segIndex = tempString.lastIndexOf('/');
	if (segIndex != -1) {
	path = path.substring(0, segIndex+1);
	}
	}
	m_path = path;
	}

	/**
	* Initialize the scheme for this URI from a URI string spec.
	*
	* @param p_uriSpec the URI specification (cannot be null)
	*
	* @exception MalformedURIException if URI does not have a conformant
	* scheme
	*/
	private void initializeScheme(String p_uriSpec)
	throws MalformedURIException {
	int uriSpecLen = p_uriSpec.length();
	int index = 0;
	String scheme = null;
	char testChar = '\0';

	while (index < uriSpecLen) {
	testChar = p_uriSpec.charAt(index);
	if (testChar == ':' \|\| testChar == '/' \|\|
	testChar == '?' \|\| testChar == '#') {
	break;
	}
	index++;
	}
	scheme = p_uriSpec.substring(0, index);

	if (scheme.length() == 0) {
	throw new MalformedURIException("No scheme found in URI.");
	}
	else {
	setScheme(scheme);
	}
	}

	/**
	* Initialize the authority (either server or registry based)
	* for this URI from a URI string spec.
	*
	* @param p_uriSpec the URI specification (cannot be null)
	*
	* @return true if the given string matched server or registry
	* based authority
	*/
	private boolean initializeAuthority(String p_uriSpec) {

	int index = 0;
	int start = 0;
	int end = p_uriSpec.length();

	char testChar = '\0';
	String userinfo = null;

	// userinfo is everything up to @
	if (p_uriSpec.indexOf('@', start) != -1) {
	while (index < end) {
	testChar = p_uriSpec.charAt(index);
	if (testChar == '@') {
	break;
	}
	index++;
	}
	userinfo = p_uriSpec.substring(start, index);
	index++;
	}

	// host is everything up to last ':', or up to
	// and including ']' if followed by ':'.
	String host = null;
	start = index;
	boolean hasPort = false;
	if (index < end) {
	if (p_uriSpec.charAt(start) == '[') {
	int bracketIndex = p_uriSpec.indexOf(']', start);
	index = (bracketIndex != -1) ? bracketIndex : end;
	if (index+1 < end && p_uriSpec.charAt(index+1) == ':') {
	++index;
	hasPort = true;
	}
	else {
	index = end;
	}
	}
	else {
	int colonIndex = p_uriSpec.lastIndexOf(':', end);
	index = (colonIndex > start) ? colonIndex : end;
	hasPort = (index != end);
	}
	}
	host = p_uriSpec.substring(start, index);
	int port = -1;
	if (host.length() > 0) {
	// port
	if (hasPort) {
	index++;
	start = index;
	while (index < end) {
	index++;
	}
	String portStr = p_uriSpec.substring(start, index);
	if (portStr.length() > 0) {
	// REVISIT: Remove this code.
	/** for (int i = 0; i < portStr.length(); i++) {
	if (!isDigit(portStr.charAt(i))) {
	throw new MalformedURIException(
	portStr +
	" is invalid. Port should only contain digits!");
	}
	}**/
	// REVISIT: Remove this code.
	// Store port value as string instead of integer.
	try {
	port = Integer.parseInt(portStr);
	if (port == -1) --port;
	}
	catch (NumberFormatException nfe) {
	port = -2;
	}
	}
	}
	}

	if (isValidServerBasedAuthority(host, port, userinfo)) {
	m_host = host;
	m_port = port;
	m_userinfo = userinfo;
	return true;
	}
	// Note: Registry based authority is being removed from a
	// new spec for URI which would obsolete RFC 2396. If the
	// spec is added to XML errata, processing of reg_name
	// needs to be removed. - mrglavas.
	else if (isValidRegistryBasedAuthority(p_uriSpec)) {
	m_regAuthority = p_uriSpec;
	return true;
	}
	return false;
	}

	/**
	* Determines whether the components host, port, and user info
	* are valid as a server authority.
	*
	* @param host the host component of authority
	* @param port the port number component of authority
	* @param userinfo the user info component of authority
	*
	* @return true if the given host, port, and userinfo compose
	* a valid server authority
	*/
	private boolean isValidServerBasedAuthority(String host, int port, String userinfo) {

	// Check if the host is well formed.
	if (!isWellFormedAddress(host)) {
	return false;
	}

	// Check that port is well formed if it exists.
	// REVISIT: There's no restriction on port value ranges, but
	// perform the same check as in setPort to be consistent. Pass
	// in a string to this method instead of an integer.
	if (port < -1 \|\| port > 65535) {
	return false;
	}

	// Check that userinfo is well formed if it exists.
	if (userinfo != null) {
	// Userinfo can contain alphanumerics, mark characters, escaped
	// and ';',':','&','=','+','$',','
	int index = 0;
	int end = userinfo.length();
	char testChar = '\0';
	while (index < end) {
	testChar = userinfo.charAt(index);
	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(userinfo.charAt(index+1)) \|\|
	!isHex(userinfo.charAt(index+2))) {
	return false;
	}
	index += 2;
	}
	else if (!isUserinfoCharacter(testChar)) {
	return false;
	}
	++index;
	}
	}
	return true;
	}

	/**
	* Determines whether the given string is a registry based authority.
	*
	* @param authority the authority component of a URI
	*
	* @return true if the given string is a registry based authority
	*/
	private boolean isValidRegistryBasedAuthority(String authority) {
	int index = 0;
	int end = authority.length();
	char testChar;

	while (index < end) {
	testChar = authority.charAt(index);

	// check for valid escape sequence
	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(authority.charAt(index+1)) \|\|
	!isHex(authority.charAt(index+2))) {
	return false;
	}
	index += 2;
	}
	// can check against path characters because the set
	// is the same except for '/' which we've already excluded.
	else if (!isPathCharacter(testChar)) {
	return false;
	}
	++index;
	}
	return true;
	}

	/**
	* Initialize the path for this URI from a URI string spec.
	*
	* @param p_uriSpec the URI specification (cannot be null)
	* @param p_nStartIndex the index to begin scanning from
	*
	* @exception MalformedURIException if p_uriSpec violates syntax rules
	*/
	private void initializePath(String p_uriSpec, int p_nStartIndex)
	throws MalformedURIException {
	if (p_uriSpec == null) {
	throw new MalformedURIException(
	"Cannot initialize path from null string!");
	}

	int index = p_nStartIndex;
	int start = p_nStartIndex;
	int end = p_uriSpec.length();
	char testChar = '\0';

	// path - everything up to query string or fragment
	if (start < end) {
	// RFC 2732 only allows '[' and ']' to appear in the opaque part.
	if (getScheme() == null \|\| p_uriSpec.charAt(start) == '/') {

	// Scan path.
	// abs_path = "/" path_segments
	// rel_path = rel_segment [ abs_path ]
	while (index < end) {
	testChar = p_uriSpec.charAt(index);

	// check for valid escape sequence
	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(p_uriSpec.charAt(index+1)) \|\|
	!isHex(p_uriSpec.charAt(index+2))) {
	throw new MalformedURIException(
	"Path contains invalid escape sequence!");
	}
	index += 2;
	}
	// Path segments cannot contain '[' or ']' since pchar
	// production was not changed by RFC 2732.
	else if (!isPathCharacter(testChar)) {
	if (testChar == '?' \|\| testChar == '#') {
	break;
	}
	throw new MalformedURIException(
	"Path contains invalid character: " + testChar);
	}
	++index;
	}
	}
	else {

	// Scan opaque part.
	// opaque_part = uric_no_slash *uric
	while (index < end) {
	testChar = p_uriSpec.charAt(index);

	if (testChar == '?' \|\| testChar == '#') {
	break;
	}

	// check for valid escape sequence
	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(p_uriSpec.charAt(index+1)) \|\|
	!isHex(p_uriSpec.charAt(index+2))) {
	throw new MalformedURIException(
	"Opaque part contains invalid escape sequence!");
	}
	index += 2;
	}
	// If the scheme specific part is opaque, it can contain '['
	// and ']'. uric_no_slash wasn't modified by RFC 2732, which
	// I've interpreted as an error in the spec, since the
	// production should be equivalent to (uric - '/'), and uric
	// contains '[' and ']'. - mrglavas
	else if (!isURICharacter(testChar)) {
	throw new MalformedURIException(
	"Opaque part contains invalid character: " + testChar);
	}
	++index;
	}
	}
	}
	m_path = p_uriSpec.substring(start, index);

	// query - starts with ? and up to fragment or end
	if (testChar == '?') {
	index++;
	start = index;
	while (index < end) {
	testChar = p_uriSpec.charAt(index);
	if (testChar == '#') {
	break;
	}
	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(p_uriSpec.charAt(index+1)) \|\|
	!isHex(p_uriSpec.charAt(index+2))) {
	throw new MalformedURIException(
	"Query string contains invalid escape sequence!");
	}
	index += 2;
	}
	else if (!isURICharacter(testChar)) {
	throw new MalformedURIException(
	"Query string contains invalid character: " + testChar);
	}
	index++;
	}
	m_queryString = p_uriSpec.substring(start, index);
	}

	// fragment - starts with #
	if (testChar == '#') {
	index++;
	start = index;
	while (index < end) {
	testChar = p_uriSpec.charAt(index);

	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(p_uriSpec.charAt(index+1)) \|\|
	!isHex(p_uriSpec.charAt(index+2))) {
	throw new MalformedURIException(
	"Fragment contains invalid escape sequence!");
	}
	index += 2;
	}
	else if (!isURICharacter(testChar)) {
	throw new MalformedURIException(
	"Fragment contains invalid character: "+testChar);
	}
	index++;
	}
	m_fragment = p_uriSpec.substring(start, index);
	}
	}

	/**
	* Get the scheme for this URI.
	*
	* @return the scheme for this URI
	*/
	public String getScheme() {
	return m_scheme;
	}

	/**
	* Get the scheme-specific part for this URI (everything following the
	* scheme and the first colon). See RFC 2396 Section 5.2 for spec.
	*
	* @return the scheme-specific part for this URI
	*/
	public String getSchemeSpecificPart() {
	final StringBuilder schemespec = new StringBuilder();

	if (m_host != null \|\| m_regAuthority != null) {
	schemespec.append("//");

	// Server based authority.
	if (m_host != null) {

	if (m_userinfo != null) {
	schemespec.append(m_userinfo);
	schemespec.append('@');
	}

	schemespec.append(m_host);

	if (m_port != -1) {
	schemespec.append(':');
	schemespec.append(m_port);
	}
	}
	// Registry based authority.
	else {
	schemespec.append(m_regAuthority);
	}
	}

	if (m_path != null) {
	schemespec.append((m_path));
	}

	if (m_queryString != null) {
	schemespec.append('?');
	schemespec.append(m_queryString);
	}

	if (m_fragment != null) {
	schemespec.append('#');
	schemespec.append(m_fragment);
	}

	return schemespec.toString();
	}

	/**
	* Get the userinfo for this URI.
	*
	* @return the userinfo for this URI (null if not specified).
	*/
	public String getUserinfo() {
	return m_userinfo;
	}

	/**
	* Get the host for this URI.
	*
	* @return the host for this URI (null if not specified).
	*/
	public String getHost() {
	return m_host;
	}

	/**
	* Get the port for this URI.
	*
	* @return the port for this URI (-1 if not specified).
	*/
	public int getPort() {
	return m_port;
	}

	/**
	* Get the registry based authority for this URI.
	*
	* @return the registry based authority (null if not specified).
	*/
	public String getRegBasedAuthority() {
	return m_regAuthority;
	}

	/**
	* Get the authority for this URI.
	*
	* @return the authority
	*/
	public String getAuthority() {
	final StringBuilder authority = new StringBuilder();
	if (m_host != null \|\| m_regAuthority != null) {
	authority.append("//");

	// Server based authority.
	if (m_host != null) {

	if (m_userinfo != null) {
	authority.append(m_userinfo);
	authority.append('@');
	}

	authority.append(m_host);

	if (m_port != -1) {
	authority.append(':');
	authority.append(m_port);
	}
	}
	// Registry based authority.
	else {
	authority.append(m_regAuthority);
	}
	}
	return authority.toString();
	}

	/**
	* Get the path for this URI (optionally with the query string and
	* fragment).
	*
	* @param p_includeQueryString if true (and query string is not null),
	* then a "?" followed by the query string
	* will be appended
	* @param p_includeFragment if true (and fragment is not null),
	* then a "#" followed by the fragment
	* will be appended
	*
	* @return the path for this URI possibly including the query string
	* and fragment
	*/
	public String getPath(boolean p_includeQueryString,
	boolean p_includeFragment) {
	final StringBuilder pathString = new StringBuilder(m_path);

	if (p_includeQueryString && m_queryString != null) {
	pathString.append('?');
	pathString.append(m_queryString);
	}

	if (p_includeFragment && m_fragment != null) {
	pathString.append('#');
	pathString.append(m_fragment);
	}
	return pathString.toString();
	}

	/**
	* Get the path for this URI. Note that the value returned is the path
	* only and does not include the query string or fragment.
	*
	* @return the path for this URI.
	*/
	public String getPath() {
	return m_path;
	}

	/**
	* Get the query string for this URI.
	*
	* @return the query string for this URI. Null is returned if there
	* was no "?" in the URI spec, empty string if there was a
	* "?" but no query string following it.
	*/
	public String getQueryString() {
	return m_queryString;
	}

	/**
	* Get the fragment for this URI.
	*
	* @return the fragment for this URI. Null is returned if there
	* was no "#" in the URI spec, empty string if there was a
	* "#" but no fragment following it.
	*/
	public String getFragment() {
	return m_fragment;
	}

	/**
	* Set the scheme for this URI. The scheme is converted to lowercase
	* before it is set.
	*
	* @param p_scheme the scheme for this URI (cannot be null)
	*
	* @exception MalformedURIException if p_scheme is not a conformant
	* scheme name
	*/
	public void setScheme(String p_scheme) throws MalformedURIException {
	if (p_scheme == null) {
	throw new MalformedURIException(
	"Cannot set scheme from null string!");
	}
	if (!isConformantSchemeName(p_scheme)) {
	throw new MalformedURIException("The scheme is not conformant.");
	}

	m_scheme = p_scheme.toLowerCase();
	}

	/**
	* Set the userinfo for this URI. If a non-null value is passed in and
	* the host value is null, then an exception is thrown.
	*
	* @param p_userinfo the userinfo for this URI
	*
	* @exception MalformedURIException if p_userinfo contains invalid
	* characters
	*/
	public void setUserinfo(String p_userinfo) throws MalformedURIException {
	if (p_userinfo == null) {
	m_userinfo = null;
	return;
	}
	else {
	if (m_host == null) {
	throw new MalformedURIException(
	"Userinfo cannot be set when host is null!");
	}

	// userinfo can contain alphanumerics, mark characters, escaped
	// and ';',':','&','=','+','$',','
	int index = 0;
	int end = p_userinfo.length();
	char testChar = '\0';
	while (index < end) {
	testChar = p_userinfo.charAt(index);
	if (testChar == '%') {
	if (index+2 >= end \|\|
	!isHex(p_userinfo.charAt(index+1)) \|\|
	!isHex(p_userinfo.charAt(index+2))) {
	throw new MalformedURIException(
	"Userinfo contains invalid escape sequence!");
	}
	}
	else if (!isUserinfoCharacter(testChar)) {
	throw new MalformedURIException(
	"Userinfo contains invalid character:"+testChar);
	}
	index++;
	}
	}
	m_userinfo = p_userinfo;
	}

	/**
	* <p>Set the host for this URI. If null is passed in, the userinfo
	* field is also set to null and the port is set to -1.</p>
	*
	* <p>Note: This method overwrites registry based authority if it
	* previously existed in this URI.</p>
	*
	* @param p_host the host for this URI
	*
	* @exception MalformedURIException if p_host is not a valid IP
	* address or DNS hostname.
	*/
	public void setHost(String p_host) throws MalformedURIException {
	if (p_host == null \|\| p_host.length() == 0) {
	if (p_host != null) {
	m_regAuthority = null;
	}
	m_host = p_host;
	m_userinfo = null;
	m_port = -1;
	return;
	}
	else if (!isWellFormedAddress(p_host)) {
	throw new MalformedURIException("Host is not a well formed address!");
	}
	m_host = p_host;
	m_regAuthority = null;
	}

	/**
	* Set the port for this URI. -1 is used to indicate that the port is
	* not specified, otherwise valid port numbers are between 0 and 65535.
	* If a valid port number is passed in and the host field is null,
	* an exception is thrown.
	*
	* @param p_port the port number for this URI
	*
	* @exception MalformedURIException if p_port is not -1 and not a
	* valid port number
	*/
	public void setPort(int p_port) throws MalformedURIException {
	if (p_port >= 0 && p_port <= 65535) {
	if (m_host == null) {
	throw new MalformedURIException(
	"Port cannot be set when host is null!");
	}
	}
	else if (p_port != -1) {
	throw new MalformedURIException("Invalid port number!");
	}
	m_port = p_port;
	}

	/**
	* <p>Sets the registry based authority for this URI.</p>
	*
	* <p>Note: This method overwrites server based authority
	* if it previously existed in this URI.</p>
	*
	* @param authority the registry based authority for this URI
	*
	* @exception MalformedURIException it authority is not a
	* well formed registry based authority
	*/
	public void setRegBasedAuthority(String authority)
	throws MalformedURIException {

	if (authority == null) {
	m_regAuthority = null;
	return;
	}
	// reg_name = 1*( unreserved \| escaped \| "$" \| "," \|
	// ";" \| ":" \| "@" \| "&" \| "=" \| "+" )
	else if (authority.length() < 1 \|\|
	!isValidRegistryBasedAuthority(authority) \|\|
	authority.indexOf('/') != -1) {
	throw new MalformedURIException("Registry based authority is not well formed.");
	}
	m_regAuthority = authority;
	m_host = null;
	m_userinfo = null;
	m_port = -1;
	}

	/**
	* Set the path for this URI. If the supplied path is null, then the
	* query string and fragment are set to null as well. If the supplied
	* path includes a query string and/or fragment, these fields will be
	* parsed and set as well. Note that, for URIs following the "generic
	* URI" syntax, the path specified should start with a slash.
	* For URIs that do not follow the generic URI syntax, this method
	* sets the scheme-specific part.
	*
	* @param p_path the path for this URI (may be null)
	*
	* @exception MalformedURIException if p_path contains invalid
	* characters
	*/
	public void setPath(String p_path) throws MalformedURIException {
	if (p_path == null) {
	m_path = null;
	m_queryString = null;
	m_fragment = null;
	}
	else {
	initializePath(p_path, 0);
	}
	}

	/**
	* Append to the end of the path of this URI. If the current path does
	* not end in a slash and the path to be appended does not begin with
	* a slash, a slash will be appended to the current path before the
	* new segment is added. Also, if the current path ends in a slash
	* and the new segment begins with a slash, the extra slash will be
	* removed before the new segment is appended.
	*
	* @param p_addToPath the new segment to be added to the current path
	*
	* @exception MalformedURIException if p_addToPath contains syntax
	* errors
	*/
	public void appendPath(String p_addToPath)
	throws MalformedURIException {
	if (p_addToPath == null \|\| p_addToPath.trim().length() == 0) {
	return;
	}

	if (!isURIString(p_addToPath)) {
	throw new MalformedURIException(
	"Path contains invalid character!");
	}

	if (m_path == null \|\| m_path.trim().length() == 0) {
	if (p_addToPath.startsWith("/")) {
	m_path = p_addToPath;
	}
	else {
	m_path = "/" + p_addToPath;
	}
	}
	else if (m_path.endsWith("/")) {
	if (p_addToPath.startsWith("/")) {
	m_path = m_path.concat(p_addToPath.substring(1));
	}
	else {
	m_path = m_path.concat(p_addToPath);
	}
	}
	else {
	if (p_addToPath.startsWith("/")) {
	m_path = m_path.concat(p_addToPath);
	}
	else {
	m_path = m_path.concat("/" + p_addToPath);
	}
	}
	}

	/**
	* Set the query string for this URI. A non-null value is valid only
	* if this is an URI conforming to the generic URI syntax and
	* the path value is not null.
	*
	* @param p_queryString the query string for this URI
	*
	* @exception MalformedURIException if p_queryString is not null and this
	* URI does not conform to the generic
	* URI syntax or if the path is null
	*/
	public void setQueryString(String p_queryString) throws MalformedURIException {
	if (p_queryString == null) {
	m_queryString = null;
	}
	else if (!isGenericURI()) {
	throw new MalformedURIException(
	"Query string can only be set for a generic URI!");
	}
	else if (getPath() == null) {
	throw new MalformedURIException(
	"Query string cannot be set when path is null!");
	}
	else if (!isURIString(p_queryString)) {
	throw new MalformedURIException(
	"Query string contains invalid character!");
	}
	else {
	m_queryString = p_queryString;
	}
	}

	/**
	* Set the fragment for this URI. A non-null value is valid only
	* if this is a URI conforming to the generic URI syntax and
	* the path value is not null.
	*
	* @param p_fragment the fragment for this URI
	*
	* @exception MalformedURIException if p_fragment is not null and this
	* URI does not conform to the generic
	* URI syntax or if the path is null
	*/
	public void setFragment(String p_fragment) throws MalformedURIException {
	if (p_fragment == null) {
	m_fragment = null;
	}
	else if (!isGenericURI()) {
	throw new MalformedURIException(
	"Fragment can only be set for a generic URI!");
	}
	else if (getPath() == null) {
	throw new MalformedURIException(
	"Fragment cannot be set when path is null!");
	}
	else if (!isURIString(p_fragment)) {
	throw new MalformedURIException(
	"Fragment contains invalid character!");
	}
	else {
	m_fragment = p_fragment;
	}
	}

	/**
	* Determines if the passed-in Object is equivalent to this URI.
	*
	* @param p_test the Object to test for equality.
	*
	* @return true if p_test is a URI with all values equal to this
	* URI, false otherwise
	*/
	@Override
	public boolean equals(Object p_test) {
	if (p_test instanceof URI) {
	URI testURI = (URI) p_test;
	if (((m_scheme == null && testURI.m_scheme == null) \|\|
	(m_scheme != null && testURI.m_scheme != null &&
	m_scheme.equals(testURI.m_scheme))) &&
	((m_userinfo == null && testURI.m_userinfo == null) \|\|
	(m_userinfo != null && testURI.m_userinfo != null &&
	m_userinfo.equals(testURI.m_userinfo))) &&
	((m_host == null && testURI.m_host == null) \|\|
	(m_host != null && testURI.m_host != null &&
	m_host.equals(testURI.m_host))) &&
	m_port == testURI.m_port &&
	((m_path == null && testURI.m_path == null) \|\|
	(m_path != null && testURI.m_path != null &&
	m_path.equals(testURI.m_path))) &&
	((m_queryString == null && testURI.m_queryString == null) \|\|
	(m_queryString != null && testURI.m_queryString != null &&
	m_queryString.equals(testURI.m_queryString))) &&
	((m_fragment == null && testURI.m_fragment == null) \|\|
	(m_fragment != null && testURI.m_fragment != null &&
	m_fragment.equals(testURI.m_fragment)))) {
	return true;
	}
	}
	return false;
	}

	@Override
	public int hashCode() {
	int hash = 5;
	hash = 47 * hash + Objects.hashCode(this.m_scheme);
	hash = 47 * hash + Objects.hashCode(this.m_userinfo);
	hash = 47 * hash + Objects.hashCode(this.m_host);
	hash = 47 * hash + this.m_port;
	hash = 47 * hash + Objects.hashCode(this.m_path);
	hash = 47 * hash + Objects.hashCode(this.m_queryString);
	hash = 47 * hash + Objects.hashCode(this.m_fragment);
	return hash;
	}

	/**
	* Get the URI as a string specification. See RFC 2396 Section 5.2.
	*
	* @return the URI string specification
	*/
	@Override
	public String toString() {
	final StringBuilder uriSpecString = new StringBuilder();

	if (m_scheme != null) {
	uriSpecString.append(m_scheme);
	uriSpecString.append(':');
	}
	uriSpecString.append(getSchemeSpecificPart());
	return uriSpecString.toString();
	}

	/**
	* Get the indicator as to whether this URI uses the "generic URI"
	* syntax.
	*
	* @return true if this URI uses the "generic URI" syntax, false
	* otherwise
	*/
	public boolean isGenericURI() {
	// presence of the host (whether valid or empty) means
	// double-slashes which means generic uri
	return (m_host != null);
	}

	/**
	* Returns whether this URI represents an absolute URI.
	*
	* @return true if this URI represents an absolute URI, false
	* otherwise
	*/
	public boolean isAbsoluteURI() {
	// presence of the scheme means absolute uri
	return (m_scheme != null);
	}

	/**
	* Determine whether a scheme conforms to the rules for a scheme name.
	* A scheme is conformant if it starts with an alphanumeric, and
	* contains only alphanumerics, '+','-' and '.'.
	*
	* @return true if the scheme is conformant, false otherwise
	*/
	public static boolean isConformantSchemeName(String p_scheme) {
	if (p_scheme == null \|\| p_scheme.trim().length() == 0) {
	return false;
	}

	if (!isAlpha(p_scheme.charAt(0))) {
	return false;
	}

	char testChar;
	int schemeLength = p_scheme.length();
	for (int i = 1; i < schemeLength; ++i) {
	testChar = p_scheme.charAt(i);
	if (!isSchemeCharacter(testChar)) {
	return false;
	}
	}

	return true;
	}

	/**
	* Determine whether a string is syntactically capable of representing
	* a valid IPv4 address, IPv6 reference or the domain name of a network host.
	* A valid IPv4 address consists of four decimal digit groups separated by a
	* '.'. Each group must consist of one to three digits. See RFC 2732 Section 3,
	* and RFC 2373 Section 2.2, for the definition of IPv6 references. A hostname
	* consists of domain labels (each of which must begin and end with an alphanumeric
	* but may contain '-') separated & by a '.'. See RFC 2396 Section 3.2.2.
	*
	* @return true if the string is a syntactically valid IPv4 address,
	* IPv6 reference or hostname
	*/
	public static boolean isWellFormedAddress(String address) {
	if (address == null) {
	return false;
	}

	int addrLength = address.length();
	if (addrLength == 0) {
	return false;
	}

	// Check if the host is a valid IPv6reference.
	if (address.startsWith("[")) {
	return isWellFormedIPv6Reference(address);
	}

	// Cannot start with a '.', '-', or end with a '-'.
	if (address.startsWith(".") \|\|
	address.startsWith("-") \|\|
	address.endsWith("-")) {
	return false;
	}

	// rightmost domain label starting with digit indicates IP address
	// since top level domain label can only start with an alpha
	// see RFC 2396 Section 3.2.2
	int index = address.lastIndexOf('.');
	if (address.endsWith(".")) {
	index = address.substring(0, index).lastIndexOf('.');
	}

	if (index+1 < addrLength && isDigit(address.charAt(index+1))) {
	return isWellFormedIPv4Address(address);
	}
	else {
	// hostname = *( domainlabel "." ) toplabel [ "." ]
	// domainlabel = alphanum \| alphanum *( alphanum \| "-" ) alphanum
	// toplabel = alpha \| alpha *( alphanum \| "-" ) alphanum

	// RFC 2396 states that hostnames take the form described in
	// RFC 1034 (Section 3) and RFC 1123 (Section 2.1). According
	// to RFC 1034, hostnames are limited to 255 characters.
	if (addrLength > 255) {
	return false;
	}

	// domain labels can contain alphanumerics and '-"
	// but must start and end with an alphanumeric
	char testChar;
	int labelCharCount = 0;

	for (int i = 0; i < addrLength; i++) {
	testChar = address.charAt(i);
	if (testChar == '.') {
	if (!isAlphanum(address.charAt(i-1))) {
	return false;
	}
	if (i+1 < addrLength && !isAlphanum(address.charAt(i+1))) {
	return false;
	}
	labelCharCount = 0;
	}
	else if (!isAlphanum(testChar) && testChar != '-') {
	return false;
	}
	// RFC 1034: Labels must be 63 characters or less.
	else if (++labelCharCount > 63) {
	return false;
	}
	}
	}
	return true;
	}

	/**
	* <p>Determines whether a string is an IPv4 address as defined by
	* RFC 2373, and under the further constraint that it must be a 32-bit
	* address. Though not expressed in the grammar, in order to satisfy
	* the 32-bit address constraint, each segment of the address cannot
	* be greater than 255 (8 bits of information).</p>
	*
	* <p><code>IPv4address = 13DIGIT "." 13DIGIT "." 13DIGIT "." 13DIGIT</code></p>
	*
	* @return true if the string is a syntactically valid IPv4 address
	*/
	public static boolean isWellFormedIPv4Address(String address) {

	int addrLength = address.length();
	char testChar;
	int numDots = 0;
	int numDigits = 0;

	// make sure that 1) we see only digits and dot separators, 2) that
	// any dot separator is preceded and followed by a digit and
	// 3) that we find 3 dots
	//
	// RFC 2732 amended RFC 2396 by replacing the definition
	// of IPv4address with the one defined by RFC 2373. - mrglavas
	//
	// IPv4address = 13DIGIT "." 13DIGIT "." 13DIGIT "." 13DIGIT
	//
	// One to three digits must be in each segment.
	for (int i = 0; i < addrLength; i++) {
	testChar = address.charAt(i);
	if (testChar == '.') {
	if ((i > 0 && !isDigit(address.charAt(i-1))) \|\|
	(i+1 < addrLength && !isDigit(address.charAt(i+1)))) {
	return false;
	}
	numDigits = 0;
	if (++numDots > 3) {
	return false;
	}
	}
	else if (!isDigit(testChar)) {
	return false;
	}
	// Check that that there are no more than three digits
	// in this segment.
	else if (++numDigits > 3) {
	return false;
	}
	// Check that this segment is not greater than 255.
	else if (numDigits == 3) {
	char first = address.charAt(i-2);
	char second = address.charAt(i-1);
	if (!(first < '2' \|\|
	(first == '2' &&
	(second < '5' \|\|
	(second == '5' && testChar <= '5'))))) {
	return false;
	}
	}
	}
	return (numDots == 3);
	}

	/**
	* <p>Determines whether a string is an IPv6 reference as defined
	* by RFC 2732, where IPv6address is defined in RFC 2373. The
	* IPv6 address is parsed according to Section 2.2 of RFC 2373,
	* with the additional constraint that the address be composed of
	* 128 bits of information.</p>
	*
	* <p><code>IPv6reference = "[" IPv6address "]"</code></p>
	*
	* <p>Note: The BNF expressed in RFC 2373 Appendix B does not
	* accurately describe section 2.2, and was in fact removed from
	* RFC 3513, the successor of RFC 2373.</p>
	*
	* @return true if the string is a syntactically valid IPv6 reference
	*/
	public static boolean isWellFormedIPv6Reference(String address) {

	int addrLength = address.length();
	int index = 1;
	int end = addrLength-1;

	// Check if string is a potential match for IPv6reference.
	if (!(addrLength > 2 && address.charAt(0) == '['
	&& address.charAt(end) == ']')) {
	return false;
	}

	// Counter for the number of 16-bit sections read in the address.
	int [] counter = new int[1];

	// Scan hex sequence before possible '::' or IPv4 address.
	index = scanHexSequence(address, index, end, counter);
	if (index == -1) {
	return false;
	}
	// Address must contain 128-bits of information.
	else if (index == end) {
	return (counter[0] == 8);
	}

	if (index+1 < end && address.charAt(index) == ':') {
	if (address.charAt(index+1) == ':') {
	// '::' represents at least one 16-bit group of zeros.
	if (++counter[0] > 8) {
	return false;
	}
	index += 2;
	// Trailing zeros will fill out the rest of the address.
	if (index == end) {
	return true;
	}
	}
	// If the second character wasn't ':', in order to be valid,
	// the remainder of the string must match IPv4Address,
	// and we must have read exactly 6 16-bit groups.
	else {
	return (counter[0] == 6) &&
	isWellFormedIPv4Address(address.substring(index+1, end));
	}
	}
	else {
	return false;
	}

	// 3. Scan hex sequence after '::'.
	int prevCount = counter[0];
	index = scanHexSequence(address, index, end, counter);

	// We've either reached the end of the string, the address ends in
	// an IPv4 address, or it is invalid. scanHexSequence has already
	// made sure that we have the right number of bits.
	return (index == end) \|\|
	(index != -1 && isWellFormedIPv4Address(
	address.substring((counter[0] > prevCount) ? index+1 : index, end)));
	}

	/**
	* Helper method for isWellFormedIPv6Reference which scans the
	* hex sequences of an IPv6 address. It returns the index of the
	* next character to scan in the address, or -1 if the string
	* cannot match a valid IPv6 address.
	*
	* @param address the string to be scanned
	* @param index the beginning index (inclusive)
	* @param end the ending index (exclusive)
	* @param counter a counter for the number of 16-bit sections read
	* in the address
	*
	* @return the index of the next character to scan, or -1 if the
	* string cannot match a valid IPv6 address
	*/
	private static int scanHexSequence (String address, int index, int end, int [] counter) {

	char testChar;
	int numDigits = 0;
	int start = index;

	// Trying to match the following productions:
	// hexseq = hex4 *( ":" hex4)
	// hex4 = 1*4HEXDIG
	for (; index < end; ++index) {
	testChar = address.charAt(index);
	if (testChar == ':') {
	// IPv6 addresses are 128-bit, so there can be at most eight sections.
	if (numDigits > 0 && ++counter[0] > 8) {
	return -1;
	}
	// This could be '::'.
	if (numDigits == 0 \|\| ((index+1 < end) && address.charAt(index+1) == ':')) {
	return index;
	}
	numDigits = 0;
	}
	// This might be invalid or an IPv4address. If it's potentially an IPv4address,
	// backup to just after the last valid character that matches hexseq.
	else if (!isHex(testChar)) {
	if (testChar == '.' && numDigits < 4 && numDigits > 0 && counter[0] <= 6) {
	int back = index - numDigits - 1;
	return (back >= start) ? back : (back+1);
	}
	return -1;
	}
	// There can be at most 4 hex digits per group.
	else if (++numDigits > 4) {
	return -1;
	}
	}
	return (numDigits > 0 && ++counter[0] <= 8) ? end : -1;
	}


	/**
	* Determine whether a char is a digit.
	*
	* @return true if the char is betweeen '0' and '9', false otherwise
	*/
	private static boolean isDigit(char p_char) {
	return p_char >= '0' && p_char <= '9';
	}

	/**
	* Determine whether a character is a hexadecimal character.
	*
	* @return true if the char is betweeen '0' and '9', 'a' and 'f'
	* or 'A' and 'F', false otherwise
	*/
	private static boolean isHex(char p_char) {
	return (p_char <= 'f' && (fgLookupTable[p_char] & ASCII_HEX_CHARACTERS) != 0);
	}

	/**
	* Determine whether a char is an alphabetic character: a-z or A-Z
	*
	* @return true if the char is alphabetic, false otherwise
	*/
	private static boolean isAlpha(char p_char) {
	return ((p_char >= 'a' && p_char <= 'z') \|\| (p_char >= 'A' && p_char <= 'Z' ));
	}

	/**
	* Determine whether a char is an alphanumeric: 0-9, a-z or A-Z
	*
	* @return true if the char is alphanumeric, false otherwise
	*/
	private static boolean isAlphanum(char p_char) {
	return (p_char <= 'z' && (fgLookupTable[p_char] & MASK_ALPHA_NUMERIC) != 0);
	}

	/**
	* Determine whether a character is a reserved character:
	* ';', '/', '?', ':', '@', '&', '=', '+', '$', ',', '[', or ']'
	*
	* @return true if the string contains any reserved characters
	*/
	private static boolean isReservedCharacter(char p_char) {
	return (p_char <= ']' && (fgLookupTable[p_char] & RESERVED_CHARACTERS) != 0);
	}

	/**
	* Determine whether a char is an unreserved character.
	*
	* @return true if the char is unreserved, false otherwise
	*/
	private static boolean isUnreservedCharacter(char p_char) {
	return (p_char <= '~' && (fgLookupTable[p_char] & MASK_UNRESERVED_MASK) != 0);
	}

	/**
	* Determine whether a char is a URI character (reserved or
	* unreserved, not including '%' for escaped octets).
	*
	* @return true if the char is a URI character, false otherwise
	*/
	private static boolean isURICharacter (char p_char) {
	return (p_char <= '~' && (fgLookupTable[p_char] & MASK_URI_CHARACTER) != 0);
	}

	/**
	* Determine whether a char is a scheme character.
	*
	* @return true if the char is a scheme character, false otherwise
	*/
	private static boolean isSchemeCharacter (char p_char) {
	return (p_char <= 'z' && (fgLookupTable[p_char] & MASK_SCHEME_CHARACTER) != 0);
	}

	/**
	* Determine whether a char is a userinfo character.
	*
	* @return true if the char is a userinfo character, false otherwise
	*/
	private static boolean isUserinfoCharacter (char p_char) {
	return (p_char <= 'z' && (fgLookupTable[p_char] & MASK_USERINFO_CHARACTER) != 0);
	}

	/**
	* Determine whether a char is a path character.
	*
	* @return true if the char is a path character, false otherwise
	*/
	private static boolean isPathCharacter (char p_char) {
	return (p_char <= '~' && (fgLookupTable[p_char] & MASK_PATH_CHARACTER) != 0);
	}


	/**
	* Determine whether a given string contains only URI characters (also
	* called "uric" in RFC 2396). uric consist of all reserved
	* characters, unreserved characters and escaped characters.
	*
	* @return true if the string is comprised of uric, false otherwise
	*/
	private static boolean isURIString(String p_uric) {
	if (p_uric == null) {
	return false;
	}
	int end = p_uric.length();
	char testChar = '\0';
	for (int i = 0; i < end; i++) {
	testChar = p_uric.charAt(i);
	if (testChar == '%') {
	if (i+2 >= end \|\|
	!isHex(p_uric.charAt(i+1)) \|\|
	!isHex(p_uric.charAt(i+2))) {
	return false;
	}
	else {
	i += 2;
	continue;
	}
	}
	if (isURICharacter(testChar)) {
	continue;
	}
	else {
	return false;
	}
	}
	return true;
	}
	}

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