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URI.javaAPI DocApache Xerces 3.0.176858Fri Sep 14 20:33:56 BST 2007org.apache.xerces.util

URI

public class URI extends Object implements Serializable
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: URI.java 447241 2006-09-18 05:12:57Z mrglavas $

Fields Summary
static final long
serialVersionUID
Serialization version.
private static final byte[]
fgLookupTable
private static final int
RESERVED_CHARACTERS
reserved characters ;/?:@&=+$,[]
private static final int
MARK_CHARACTERS
URI punctuation mark characters: -_.!~*'() - these, combined with alphanumerics, constitute the "unreserved" characters
private static final int
SCHEME_CHARACTERS
scheme can be composed of alphanumerics and these characters: +-.
private static final int
USERINFO_CHARACTERS
userinfo can be composed of unreserved, escaped and these characters: ;:&=+$,
private static final int
ASCII_ALPHA_CHARACTERS
ASCII letter characters
private static final int
ASCII_DIGIT_CHARACTERS
ASCII digit characters
private static final int
ASCII_HEX_CHARACTERS
ASCII hex characters
private static final int
PATH_CHARACTERS
Path characters
private static final int
MASK_ALPHA_NUMERIC
Mask for alpha-numeric characters
private static final int
MASK_UNRESERVED_MASK
Mask for unreserved characters
private static final int
MASK_URI_CHARACTER
Mask for URI allowable characters except for %
private static final int
MASK_SCHEME_CHARACTER
Mask for scheme characters
private static final int
MASK_USERINFO_CHARACTER
Mask for userinfo characters
private static final int
MASK_PATH_CHARACTER
Mask for path characters
private String
m_scheme
Stores the scheme (usually the protocol) for this URI.
private String
m_userinfo
If specified, stores the userinfo for this URI; otherwise null
private String
m_host
If specified, stores the host for this URI; otherwise null
private int
m_port
If specified, stores the port for this URI; otherwise -1
private String
m_regAuthority
If specified, stores the registry based authority for this URI; otherwise -1
private String
m_path
If specified, stores the path for this URI; otherwise null
private String
m_queryString
If specified, stores the query string for this URI; otherwise null.
private String
m_fragment
If specified, stores the fragment for this URI; otherwise null
private static boolean
DEBUG
Constructors Summary
public URI()
Construct a new and uninitialized URI.
public URI(URI p_other)
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)

    initialize(p_other);
public URI(String 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.

param
p_uriSpec the URI specification string (cannot be null or empty)
exception
MalformedURIException if p_uriSpec violates any syntax rules

    this((URI)null, p_uriSpec);
public URI(String p_uriSpec, boolean allowNonAbsoluteURI)
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

      this((URI)null, p_uriSpec, allowNonAbsoluteURI);
public URI(URI p_base, String p_uriSpec)
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

    initialize(p_base, p_uriSpec);
public URI(URI p_base, String p_uriSpec, boolean allowNonAbsoluteURI)
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

      initialize(p_base, p_uriSpec, allowNonAbsoluteURI);
public URI(String p_scheme, String p_schemeSpecificPart)
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

    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);
public URI(String p_scheme, String p_host, String p_path, String p_queryString, String 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_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

    this(p_scheme, null, p_host, -1, p_path, p_queryString, p_fragment);
public URI(String p_scheme, String p_userinfo, String p_host, int p_port, String p_path, String p_queryString, String 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

    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);
Methods Summary
public voidabsolutize(org.apache.xerces.util.URI p_base)
Absolutize URI with given base URI.

param
p_base base URI for absolutization


      // 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;
public voidappendPath(java.lang.String p_addToPath)
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

    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);
      }
    }
public booleanequals(java.lang.Object p_test)
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

    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;
public java.lang.StringgetAuthority()
Get the authority for this URI.

return
the authority

      StringBuffer authority = new StringBuffer();
      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();
public java.lang.StringgetFragment()
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.

    return m_fragment;
public java.lang.StringgetHost()
Get the host for this URI.

return
the host for this URI (null if not specified).

    return m_host;
public java.lang.StringgetPath(boolean p_includeQueryString, boolean p_includeFragment)
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

    StringBuffer pathString = new StringBuffer(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();
public java.lang.StringgetPath()
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.

    return m_path;
public intgetPort()
Get the port for this URI.

return
the port for this URI (-1 if not specified).

    return m_port;
public java.lang.StringgetQueryString()
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.

    return m_queryString;
public java.lang.StringgetRegBasedAuthority()
Get the registry based authority for this URI.

return
the registry based authority (null if not specified).

    return m_regAuthority;
public java.lang.StringgetScheme()
Get the scheme for this URI.

return
the scheme for this URI

    return m_scheme;
public java.lang.StringgetSchemeSpecificPart()
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

    StringBuffer schemespec = new StringBuffer();

    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();
public java.lang.StringgetUserinfo()
Get the userinfo for this URI.

return
the userinfo for this URI (null if not specified).

    return m_userinfo;
private voidinitialize(org.apache.xerces.util.URI p_other)
Initialize all fields of this URI from another URI.

param
p_other the URI to copy (cannot be null)

    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();
private voidinitialize(org.apache.xerces.util.URI p_base, java.lang.String p_uriSpec, boolean allowNonAbsoluteURI)
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

      
      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);
      }
private voidinitialize(org.apache.xerces.util.URI p_base, java.lang.String p_uriSpec)
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

	  
    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 {
        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);
    }
private booleaninitializeAuthority(java.lang.String p_uriSpec)
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

    
    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;
private voidinitializePath(java.lang.String p_uriSpec, int p_nStartIndex)
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

    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);
    }
private voidinitializeScheme(java.lang.String p_uriSpec)
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

    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);
    }
public booleanisAbsoluteURI()
Returns whether this URI represents an absolute URI.

return
true if this URI represents an absolute URI, false otherwise

      // presence of the scheme means absolute uri
      return (m_scheme != null);
private static booleanisAlpha(char p_char)
Determine whether a char is an alphabetic character: a-z or A-Z

return
true if the char is alphabetic, false otherwise

      return ((p_char >= 'a" && p_char <= 'z") || (p_char >= 'A" && p_char <= 'Z" ));
private static booleanisAlphanum(char p_char)
Determine whether a char is an alphanumeric: 0-9, a-z or A-Z

return
true if the char is alphanumeric, false otherwise

     return (p_char <= 'z" && (fgLookupTable[p_char] & MASK_ALPHA_NUMERIC) != 0);
public static booleanisConformantSchemeName(java.lang.String p_scheme)
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

    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;
private static booleanisDigit(char p_char)
Determine whether a char is a digit.

return
true if the char is betweeen '0' and '9', false otherwise

    return p_char >= '0" && p_char <= '9";
public booleanisGenericURI()
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

    // presence of the host (whether valid or empty) means
    // double-slashes which means generic uri
    return (m_host != null);
private static booleanisHex(char p_char)
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

    return (p_char <= 'f" && (fgLookupTable[p_char] & ASCII_HEX_CHARACTERS) != 0);
private static booleanisPathCharacter(char p_char)
Determine whether a char is a path character.

return
true if the char is a path character, false otherwise

      return (p_char <= '~" && (fgLookupTable[p_char] & MASK_PATH_CHARACTER) != 0);
private static booleanisReservedCharacter(char p_char)
Determine whether a character is a reserved character: ';', '/', '?', ':', '@', '&', '=', '+', '$', ',', '[', or ']'

return
true if the string contains any reserved characters

     return (p_char <= ']" && (fgLookupTable[p_char] & RESERVED_CHARACTERS) != 0);
private static booleanisSchemeCharacter(char p_char)
Determine whether a char is a scheme character.

return
true if the char is a scheme character, false otherwise

      return (p_char <= 'z" && (fgLookupTable[p_char] & MASK_SCHEME_CHARACTER) != 0);
private static booleanisURICharacter(char p_char)
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

      return (p_char <= '~" && (fgLookupTable[p_char] & MASK_URI_CHARACTER) != 0);
private static booleanisURIString(java.lang.String p_uric)
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

    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;
private static booleanisUnreservedCharacter(char p_char)
Determine whether a char is an unreserved character.

return
true if the char is unreserved, false otherwise

     return (p_char <= '~" && (fgLookupTable[p_char] & MASK_UNRESERVED_MASK) != 0);
private static booleanisUserinfoCharacter(char p_char)
Determine whether a char is a userinfo character.

return
true if the char is a userinfo character, false otherwise

      return (p_char <= 'z" && (fgLookupTable[p_char] & MASK_USERINFO_CHARACTER) != 0);
private booleanisValidRegistryBasedAuthority(java.lang.String authority)
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

    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;
private booleanisValidServerBasedAuthority(java.lang.String host, int port, java.lang.String userinfo)
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

    
    // 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;
public static booleanisWellFormedAddress(java.lang.String address)
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

    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;
public static booleanisWellFormedIPv4Address(java.lang.String address)

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

return
true if the string is a syntactically valid IPv4 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);
public static booleanisWellFormedIPv6Reference(java.lang.String address)

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.

return
true if the string is a syntactically valid IPv6 reference


      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)));
private static intscanHexSequence(java.lang.String address, int index, int end, int[] counter)
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

  	
      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;
public voidsetFragment(java.lang.String p_fragment)
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

    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;
    }
public voidsetHost(java.lang.String p_host)

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.

    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;
public voidsetPath(java.lang.String p_path)
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

    if (p_path == null) {
      m_path = null;
      m_queryString = null;
      m_fragment = null;
    }
    else {
      initializePath(p_path, 0);
    }
public voidsetPort(int p_port)
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

    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;
public voidsetQueryString(java.lang.String p_queryString)
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

    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;
    }
public voidsetRegBasedAuthority(java.lang.String authority)

Sets the registry based authority for this URI.

Note: This method overwrites server based authority if it previously existed in this URI.

param
authority the registry based authority for this URI
exception
MalformedURIException it authority is not a well formed registry based authority


  	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;
public voidsetScheme(java.lang.String p_scheme)
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

    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();
public voidsetUserinfo(java.lang.String p_userinfo)
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

    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;
public java.lang.StringtoString()
Get the URI as a string specification. See RFC 2396 Section 5.2.

return
the URI string specification

    StringBuffer uriSpecString = new StringBuffer();

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