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/*
* 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 net.sourceforge.htmlunit.xerces.util;
import java.io.IOException;
import java.util.Locale;
/**********************************************************************
* 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.
*
* Parsing of a URI specification is done according to the URI
* syntax described in
* RFC 2396,
* and amended by
* RFC 2732.
*
* 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.
*
* 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.
*
* 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.
*
* @version $Id$
*
**********************************************************************/
public class URI {
/*******************************************************************
* 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 {
private static final long serialVersionUID = -8343545858797571098L;
/*****************************************************************
* Constructs a MalformedURIException with the
* specified detail message.
*
* @param p_msg the detail message.
******************************************************************/
public MalformedURIException(String p_msg) {
super(p_msg);
}
}
private static final byte [] fgLookupTable = new byte[128];
/** 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;
/**
* 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(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 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 {
int uriSpecLen = (p_uriSpec != null) ? p_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 = p_uriSpec.indexOf(':');
if (colonIdx != -1) {
final int searchFrom = colonIdx - 1;
// search backwards starting from character before ':'.
int slashIdx = p_uriSpec.lastIndexOf('/', searchFrom);
int queryIdx = p_uriSpec.lastIndexOf('?', searchFrom);
int fragmentIdx = p_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(p_uriSpec);
index = m_scheme.length()+1;
// Neither 'scheme:' or 'scheme:#fragment' are valid URIs.
if (colonIdx == uriSpecLen - 1 || p_uriSpec.charAt(colonIdx+1) == '#') {
throw new MalformedURIException("Scheme specific part cannot be empty.");
}
}
}
else if (p_base == null && p_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) &&
(p_uriSpec.charAt(index) == '/' && p_uriSpec.charAt(index+1) == '/')) {
index += 2;
int startPos = index;
// Authority will be everything up to path, query or fragment
while (index < uriSpecLen) {
char testChar = p_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(p_uriSpec.substring(startPos, index))) {
index = startPos - 2;
}
}
else {
m_host = "";
}
}
initializePath(p_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 {
int uriSpecLen = (p_uriSpec != null) ? p_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 = p_uriSpec.indexOf(':');
if (colonIdx != -1) {
final int searchFrom = colonIdx - 1;
// search backwards starting from character before ':'.
int slashIdx = p_uriSpec.lastIndexOf('/', searchFrom);
int queryIdx = p_uriSpec.lastIndexOf('?', searchFrom);
int fragmentIdx = p_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(p_uriSpec);
index = m_scheme.length()+1;
// Neither 'scheme:' or 'scheme:#fragment' are valid URIs.
if (colonIdx == uriSpecLen - 1 || p_uriSpec.charAt(colonIdx+1) == '#') {
throw new MalformedURIException("Scheme specific part cannot be empty.");
}
}
}
else if (p_base == null && p_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) &&
(p_uriSpec.charAt(index) == '/' && p_uriSpec.charAt(index+1) == '/')) {
index += 2;
int startPos = index;
// Authority will be everything up to path, query or fragment
while (index < uriSpecLen) {
char testChar = p_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(p_uriSpec.substring(startPos, index))) {
index = startPos - 2;
}
}
else {
m_host = "";
}
}
initializePath(p_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 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;
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 "/../" where "" 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 "/.." where "" 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;
while (index < uriSpecLen) {
char 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();
String userinfo = null;
// userinfo is everything up to @
if (p_uriSpec.indexOf('@', start) != -1) {
while (index < end) {
char 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.
// 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.
// 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 (!isWellFormedAddress(host) || 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();
while (index < end) {
char 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() {
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 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(Locale.ROOT);
}
/**
* 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();
while (index < end) {
char 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;
}
/**
* 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.
*
* Note: This method overwrites registry based authority if it
* previously existed in this URI.
*
* @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;
}
/**
* 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);
}
}
/**
* 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;
}
/**
* Get the URI as a string specification. See RFC 2396 Section 5.2.
*
* @return the URI string specification
*/
@Override
public String toString() {
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 '.'.
* @param p_scheme the scheme
*
* @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 || !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.
*
* @param address the address
* @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)) || (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;
}
/**
* 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).
*
* IPv4address = 1*3DIGIT "." 1*3DIGIT "." 1*3DIGIT "." 1*3DIGIT
*
* @param address the address
* @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 = 1*3DIGIT "." 1*3DIGIT "." 1*3DIGIT "." 1*3DIGIT
//
// 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);
}
/**
* 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.
*
* IPv6reference = "[" IPv6address "]"
*
* 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.
*
* @param address the address
* @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 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();
for (int i = 0; i < end; i++) {
char 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;
}
}