Class URI


  • public class URI
    extends java.lang.Object
    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.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  URI.MalformedURIException
      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.
    • Field Summary

      Fields 
      Modifier and Type Field Description
      private static int ASCII_ALPHA_CHARACTERS
      ASCII letter characters
      private static int ASCII_DIGIT_CHARACTERS
      ASCII digit characters
      private static int ASCII_HEX_CHARACTERS
      ASCII hex characters
      private static byte[] fgLookupTable  
      private java.lang.String fragment_
      If specified, stores the fragment for this URI; otherwise null
      private java.lang.String host_
      If specified, stores the host for this URI; otherwise null
      private static int MARK_CHARACTERS
      URI punctuation mark characters: -_.!~*'() - these, combined with alphanumerics, constitute the "unreserved" characters
      private static int MASK_ALPHA_NUMERIC
      Mask for alpha-numeric characters
      private static int MASK_PATH_CHARACTER
      Mask for path characters
      private static int MASK_SCHEME_CHARACTER
      Mask for scheme characters
      private static int MASK_UNRESERVED_MASK
      Mask for unreserved characters
      private static int MASK_URI_CHARACTER
      Mask for URI allowable characters except for %
      private static int MASK_USERINFO_CHARACTER
      Mask for userinfo characters
      private java.lang.String path_
      If specified, stores the path for this URI; otherwise null
      private static int PATH_CHARACTERS
      Path characters
      private int port_
      If specified, stores the port for this URI; otherwise -1
      private java.lang.String queryString_
      If specified, stores the query string for this URI; otherwise null.
      private java.lang.String regAuthority_
      If specified, stores the registry based authority for this URI; otherwise -1
      private static int RESERVED_CHARACTERS
      reserved characters ;/?:@&=+$,[]
      private java.lang.String scheme_
      Stores the scheme (usually the protocol) for this URI.
      private static int SCHEME_CHARACTERS
      scheme can be composed of alphanumerics and these characters: +-.
      private java.lang.String userinfo_
      If specified, stores the userinfo for this URI; otherwise null
      private static int USERINFO_CHARACTERS
      userinfo can be composed of unreserved, escaped and these characters: ;:&=+$,
    • Constructor Summary

      Constructors 
      Constructor Description
      URI​(java.lang.String uriSpec)
      Construct a new URI from a URI specification string.
      URI​(java.lang.String uriSpec, boolean allowNonAbsoluteURI)
      Construct a new URI from a URI specification string.
      URI​(java.lang.String scheme, java.lang.String userinfo, java.lang.String host, int port, java.lang.String path, java.lang.String queryString, java.lang.String fragment)
      Construct a new URI that follows the generic URI syntax from its component parts.
      URI​(java.lang.String scheme, java.lang.String host, java.lang.String path, java.lang.String queryString, java.lang.String fragment)
      Construct a new URI that follows the generic URI syntax from its component parts.
      URI​(URI base, java.lang.String uriSpec)
      Construct a new URI from a base URI and a URI specification string.
      URI​(URI base, java.lang.String uriSpec, boolean allowNonAbsoluteURI)
      Construct a new URI from a base URI and a URI specification string.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void absolutize​(URI base)
      Absolutize URI with given base URI.
      boolean equals​(java.lang.Object test)
      Determines if the passed-in Object is equivalent to this URI.
      java.lang.String getFragment()
      Get the fragment for this URI.
      java.lang.String getHost()
      Get the host for this URI.
      java.lang.String getPath()
      Get the path for this URI.
      int getPort()
      Get the port for this URI.
      java.lang.String getQueryString()
      Get the query string for this URI.
      java.lang.String getRegBasedAuthority()
      Get the registry based authority for this URI.
      java.lang.String getScheme()
      Get the scheme for this URI.
      java.lang.String getSchemeSpecificPart()
      Get the scheme-specific part for this URI (everything following the scheme and the first colon).
      java.lang.String getUserinfo()
      Get the userinfo for this URI.
      private void initialize​(URI other)
      Initialize all fields of this URI from another URI.
      private void initialize​(URI base, java.lang.String uriSpec)
      Initializes this URI from a base URI and a URI specification string.
      private void initialize​(URI base, java.lang.String uriSpec, boolean allowNonAbsoluteURI)
      Initializes this URI from a base URI and a URI specification string.
      private boolean initializeAuthority​(java.lang.String uriSpec)
      Initialize the authority (either server or registry based) for this URI from a URI string spec.
      private void initializePath​(java.lang.String uriSpec, int nStartIndex)
      Initialize the path for this URI from a URI string spec.
      private void initializeScheme​(java.lang.String uriSpec)
      Initialize the scheme for this URI from a URI string spec.
      boolean isAbsoluteURI()
      Returns whether this URI represents an absolute URI.
      private static boolean isAlpha​(char ch)
      Determine whether a char is an alphabetic character: a-z or A-Z
      private static boolean isAlphanum​(char ch)
      Determine whether a char is an alphanumeric: 0-9, a-z or A-Z
      private static boolean isConformantSchemeName​(java.lang.String scheme)
      Determine whether a scheme conforms to the rules for a scheme name.
      private static boolean isDigit​(char chr)
      Determine whether a char is a digit.
      boolean isGenericURI()
      Get the indicator as to whether this URI uses the "generic URI" syntax.
      private static boolean isHex​(char ch)
      Determine whether a character is a hexadecimal character.
      private static boolean isPathCharacter​(char ch)
      Determine whether a char is a path character.
      private static boolean isSchemeCharacter​(char ch)
      Determine whether a char is a scheme character.
      private static boolean isURICharacter​(char ch)
      Determine whether a char is a URI character (reserved or unreserved, not including '%' for escaped octets).
      private static boolean isURIString​(java.lang.String uric)
      Determine whether a given string contains only URI characters (also called "uric" in RFC 2396).
      private static boolean isUserinfoCharacter​(char ch)
      Determine whether a char is a userinfo character.
      private boolean isValidRegistryBasedAuthority​(java.lang.String authority)
      Determines whether the given string is a registry based authority.
      private boolean isValidServerBasedAuthority​(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.
      static boolean isWellFormedAddress​(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.
      static boolean isWellFormedIPv4Address​(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.
      static boolean isWellFormedIPv6Reference​(java.lang.String address)
      Determines whether a string is an IPv6 reference as defined by RFC 2732, where IPv6address is defined in RFC 2373.
      private static int scanHexSequence​(java.lang.String address, int index, int end, int[] counter)
      Helper method for isWellFormedIPv6Reference which scans the hex sequences of an IPv6 address.
      void setFragment​(java.lang.String fragment)
      Set the fragment for this URI.
      void setHost​(java.lang.String host)
      Set the host for this URI.
      void setPath​(java.lang.String path)
      Set the path for this URI.
      void setPort​(int port)
      Set the port for this URI.
      void setQueryString​(java.lang.String queryString)
      Set the query string for this URI.
      void setScheme​(java.lang.String scheme)
      Set the scheme for this URI.
      void setUserinfo​(java.lang.String userinfo)
      Set the userinfo for this URI.
      java.lang.String toString()
      Get the URI as a string specification.
      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
    • Field Detail

      • fgLookupTable

        private static final byte[] fgLookupTable
      • RESERVED_CHARACTERS

        private static final int RESERVED_CHARACTERS
        reserved characters ;/?:@&=+$,[]
        See Also:
        Constant Field Values
      • MARK_CHARACTERS

        private static final int MARK_CHARACTERS
        URI punctuation mark characters: -_.!~*'() - these, combined with alphanumerics, constitute the "unreserved" characters
        See Also:
        Constant Field Values
      • SCHEME_CHARACTERS

        private static final int SCHEME_CHARACTERS
        scheme can be composed of alphanumerics and these characters: +-.
        See Also:
        Constant Field Values
      • USERINFO_CHARACTERS

        private static final int USERINFO_CHARACTERS
        userinfo can be composed of unreserved, escaped and these characters: ;:&=+$,
        See Also:
        Constant Field Values
      • ASCII_ALPHA_CHARACTERS

        private static final int ASCII_ALPHA_CHARACTERS
        ASCII letter characters
        See Also:
        Constant Field Values
      • ASCII_DIGIT_CHARACTERS

        private static final int ASCII_DIGIT_CHARACTERS
        ASCII digit characters
        See Also:
        Constant Field Values
      • ASCII_HEX_CHARACTERS

        private static final int ASCII_HEX_CHARACTERS
        ASCII hex characters
        See Also:
        Constant Field Values
      • PATH_CHARACTERS

        private static final int PATH_CHARACTERS
        Path characters
        See Also:
        Constant Field Values
      • MASK_ALPHA_NUMERIC

        private static final int MASK_ALPHA_NUMERIC
        Mask for alpha-numeric characters
        See Also:
        Constant Field Values
      • MASK_UNRESERVED_MASK

        private static final int MASK_UNRESERVED_MASK
        Mask for unreserved characters
        See Also:
        Constant Field Values
      • MASK_URI_CHARACTER

        private static final int MASK_URI_CHARACTER
        Mask for URI allowable characters except for %
        See Also:
        Constant Field Values
      • MASK_SCHEME_CHARACTER

        private static final int MASK_SCHEME_CHARACTER
        Mask for scheme characters
        See Also:
        Constant Field Values
      • MASK_USERINFO_CHARACTER

        private static final int MASK_USERINFO_CHARACTER
        Mask for userinfo characters
        See Also:
        Constant Field Values
      • MASK_PATH_CHARACTER

        private static final int MASK_PATH_CHARACTER
        Mask for path characters
        See Also:
        Constant Field Values
      • scheme_

        private java.lang.String scheme_
        Stores the scheme (usually the protocol) for this URI.
      • userinfo_

        private java.lang.String userinfo_
        If specified, stores the userinfo for this URI; otherwise null
      • host_

        private java.lang.String host_
        If specified, stores the host for this URI; otherwise null
      • port_

        private int port_
        If specified, stores the port for this URI; otherwise -1
      • regAuthority_

        private java.lang.String regAuthority_
        If specified, stores the registry based authority for this URI; otherwise -1
      • path_

        private java.lang.String path_
        If specified, stores the path for this URI; otherwise null
      • queryString_

        private java.lang.String queryString_
        If specified, stores the query string for this URI; otherwise null.
      • fragment_

        private java.lang.String fragment_
        If specified, stores the fragment for this URI; otherwise null
    • Constructor Detail

      • URI

        public URI​(java.lang.String uriSpec)
            throws URI.MalformedURIException
        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.
        Parameters:
        uriSpec - the URI specification string (cannot be null or empty)
        Throws:
        URI.MalformedURIException - if p_uriSpec violates any syntax rules
      • URI

        public URI​(java.lang.String uriSpec,
                   boolean allowNonAbsoluteURI)
            throws URI.MalformedURIException
        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.
        Parameters:
        uriSpec - the URI specification string (cannot be null or empty)
        allowNonAbsoluteURI - true to permit non-absolute URIs, false otherwise.
        Throws:
        URI.MalformedURIException - if p_uriSpec violates any syntax rules
      • URI

        public URI​(URI base,
                   java.lang.String uriSpec)
            throws URI.MalformedURIException
        Construct a new URI from a base URI and a URI specification string. The URI specification string may be a relative URI.
        Parameters:
        base - the base URI (cannot be null if p_uriSpec is null or empty)
        uriSpec - the URI specification string (cannot be null or empty if p_base is null)
        Throws:
        URI.MalformedURIException - if p_uriSpec violates any syntax rules
      • URI

        public URI​(URI base,
                   java.lang.String uriSpec,
                   boolean allowNonAbsoluteURI)
            throws URI.MalformedURIException
        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.
        Parameters:
        base - the base URI (cannot be null if p_uriSpec is null or empty)
        uriSpec - the URI specification string (cannot be null or empty if p_base is null)
        allowNonAbsoluteURI - true to permit non-absolute URIs, false otherwise.
        Throws:
        URI.MalformedURIException - if p_uriSpec violates any syntax rules
      • URI

        public URI​(java.lang.String scheme,
                   java.lang.String host,
                   java.lang.String path,
                   java.lang.String queryString,
                   java.lang.String fragment)
            throws URI.MalformedURIException
        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.
        Parameters:
        scheme - the URI scheme (cannot be null or empty)
        host - the hostname, IPv4 address or IPv6 reference for the URI
        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
        queryString - the URI query string (cannot be specified if path is null)
        fragment - the URI fragment (cannot be specified if path is null)
        Throws:
        URI.MalformedURIException - if any of the parameters violates syntax rules or semantic rules
      • URI

        public URI​(java.lang.String scheme,
                   java.lang.String userinfo,
                   java.lang.String host,
                   int port,
                   java.lang.String path,
                   java.lang.String queryString,
                   java.lang.String fragment)
            throws URI.MalformedURIException
        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.
        Parameters:
        scheme - the URI scheme (cannot be null or empty)
        userinfo - the URI userinfo (cannot be specified if host is null)
        host - the hostname, IPv4 address or IPv6 reference for the URI
        port - the URI port (may be -1 for "unspecified"; cannot be specified if host is null)
        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
        queryString - the URI query string (cannot be specified if path is null)
        fragment - the URI fragment (cannot be specified if path is null)
        Throws:
        URI.MalformedURIException - if any of the parameters violates syntax rules or semantic rules
    • Method Detail

      • initialize

        private void initialize​(URI other)
        Initialize all fields of this URI from another URI.
        Parameters:
        other - the URI to copy (cannot be null)
      • initialize

        private void initialize​(URI base,
                                java.lang.String uriSpec,
                                boolean allowNonAbsoluteURI)
                         throws URI.MalformedURIException
        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.
        Parameters:
        base - the base URI (may be null if p_uriSpec is an absolute URI)
        uriSpec - the URI spec string which may be an absolute or relative URI (can only be null/empty if p_base is not null)
        allowNonAbsoluteURI - true to permit non-absolute URIs, in case of relative URI, false otherwise.
        Throws:
        URI.MalformedURIException - if p_base is null and p_uriSpec is not an absolute URI or if p_uriSpec violates syntax rules
      • initialize

        private void initialize​(URI base,
                                java.lang.String uriSpec)
                         throws URI.MalformedURIException
        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.
        Parameters:
        base - the base URI (may be null if p_uriSpec is an absolute URI)
        uriSpec - the URI spec string which may be an absolute or relative URI (can only be null/empty if p_base is not null)
        Throws:
        URI.MalformedURIException - if p_base is null and p_uriSpec is not an absolute URI or if p_uriSpec violates syntax rules
      • absolutize

        public void absolutize​(URI base)
        Absolutize URI with given base URI.
        Parameters:
        base - base URI for absolutization
      • initializeScheme

        private void initializeScheme​(java.lang.String uriSpec)
                               throws URI.MalformedURIException
        Initialize the scheme for this URI from a URI string spec.
        Parameters:
        uriSpec - the URI specification (cannot be null)
        Throws:
        URI.MalformedURIException - if URI does not have a conformant scheme
      • initializeAuthority

        private boolean initializeAuthority​(java.lang.String uriSpec)
        Initialize the authority (either server or registry based) for this URI from a URI string spec.
        Parameters:
        uriSpec - the URI specification (cannot be null)
        Returns:
        true if the given string matched server or registry based authority
      • isValidServerBasedAuthority

        private boolean isValidServerBasedAuthority​(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.
        Parameters:
        host - the host component of authority
        port - the port number component of authority
        userinfo - the user info component of authority
        Returns:
        true if the given host, port, and userinfo compose a valid server authority
      • isValidRegistryBasedAuthority

        private boolean isValidRegistryBasedAuthority​(java.lang.String authority)
        Determines whether the given string is a registry based authority.
        Parameters:
        authority - the authority component of a URI
        Returns:
        true if the given string is a registry based authority
      • initializePath

        private void initializePath​(java.lang.String uriSpec,
                                    int nStartIndex)
                             throws URI.MalformedURIException
        Initialize the path for this URI from a URI string spec.
        Parameters:
        uriSpec - the URI specification (cannot be null)
        nStartIndex - the index to begin scanning from
        Throws:
        URI.MalformedURIException - if p_uriSpec violates syntax rules
      • getScheme

        public java.lang.String getScheme()
        Get the scheme for this URI.
        Returns:
        the scheme for this URI
      • getSchemeSpecificPart

        public java.lang.String getSchemeSpecificPart()
        Get the scheme-specific part for this URI (everything following the scheme and the first colon). See RFC 2396 Section 5.2 for spec.
        Returns:
        the scheme-specific part for this URI
      • getUserinfo

        public java.lang.String getUserinfo()
        Get the userinfo for this URI.
        Returns:
        the userinfo for this URI (null if not specified).
      • getHost

        public java.lang.String getHost()
        Get the host for this URI.
        Returns:
        the host for this URI (null if not specified).
      • getPort

        public int getPort()
        Get the port for this URI.
        Returns:
        the port for this URI (-1 if not specified).
      • getRegBasedAuthority

        public java.lang.String getRegBasedAuthority()
        Get the registry based authority for this URI.
        Returns:
        the registry based authority (null if not specified).
      • getPath

        public java.lang.String getPath()
        Get the path for this URI. Note that the value returned is the path only and does not include the query string or fragment.
        Returns:
        the path for this URI.
      • getQueryString

        public java.lang.String getQueryString()
        Get the query string for this URI.
        Returns:
        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.
      • getFragment

        public java.lang.String getFragment()
        Get the fragment for this URI.
        Returns:
        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.
      • setScheme

        public void setScheme​(java.lang.String scheme)
                       throws URI.MalformedURIException
        Set the scheme for this URI. The scheme is converted to lowercase before it is set.
        Parameters:
        scheme - the scheme for this URI (cannot be null)
        Throws:
        URI.MalformedURIException - if p_scheme is not a conformant scheme name
      • setUserinfo

        public void setUserinfo​(java.lang.String userinfo)
                         throws URI.MalformedURIException
        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.
        Parameters:
        userinfo - the userinfo for this URI
        Throws:
        URI.MalformedURIException - if p_userinfo contains invalid characters
      • setHost

        public void setHost​(java.lang.String host)
                     throws URI.MalformedURIException

        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.

        Parameters:
        host - the host for this URI
        Throws:
        URI.MalformedURIException - if p_host is not a valid IP address or DNS hostname.
      • setPort

        public void setPort​(int port)
                     throws URI.MalformedURIException
        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.
        Parameters:
        port - the port number for this URI
        Throws:
        URI.MalformedURIException - if p_port is not -1 and not a valid port number
      • setPath

        public void setPath​(java.lang.String path)
                     throws URI.MalformedURIException
        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.
        Parameters:
        path - the path for this URI (may be null)
        Throws:
        URI.MalformedURIException - if p_path contains invalid characters
      • setQueryString

        public void setQueryString​(java.lang.String queryString)
                            throws URI.MalformedURIException
        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.
        Parameters:
        queryString - the query string for this URI
        Throws:
        URI.MalformedURIException - if p_queryString is not null and this URI does not conform to the generic URI syntax or if the path is null
      • setFragment

        public void setFragment​(java.lang.String fragment)
                         throws URI.MalformedURIException
        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.
        Parameters:
        fragment - the fragment for this URI
        Throws:
        URI.MalformedURIException - if p_fragment is not null and this URI does not conform to the generic URI syntax or if the path is null
      • equals

        public boolean equals​(java.lang.Object test)
        Determines if the passed-in Object is equivalent to this URI.
        Overrides:
        equals in class java.lang.Object
        Parameters:
        test - the Object to test for equality.
        Returns:
        true if p_test is a URI with all values equal to this URI, false otherwise
      • toString

        public java.lang.String toString()
        Get the URI as a string specification. See RFC 2396 Section 5.2.
        Overrides:
        toString in class java.lang.Object
        Returns:
        the URI string specification
      • isGenericURI

        public boolean isGenericURI()
        Get the indicator as to whether this URI uses the "generic URI" syntax.
        Returns:
        true if this URI uses the "generic URI" syntax, false otherwise
      • isAbsoluteURI

        public boolean isAbsoluteURI()
        Returns whether this URI represents an absolute URI.
        Returns:
        true if this URI represents an absolute URI, false otherwise
      • isConformantSchemeName

        private static boolean isConformantSchemeName​(java.lang.String 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 '.'.
        Parameters:
        scheme - the scheme
        Returns:
        true if the scheme is conformant, false otherwise
      • isWellFormedAddress

        public static boolean isWellFormedAddress​(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.
        Parameters:
        address - the address
        Returns:
        true if the string is a syntactically valid IPv4 address, IPv6 reference or hostname
      • isWellFormedIPv4Address

        public static boolean isWellFormedIPv4Address​(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

        Parameters:
        address - the address
        Returns:
        true if the string is a syntactically valid IPv4 address
      • isWellFormedIPv6Reference

        public static boolean isWellFormedIPv6Reference​(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.

        Parameters:
        address - the address
        Returns:
        true if the string is a syntactically valid IPv6 reference
      • scanHexSequence

        private static int scanHexSequence​(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.
        Parameters:
        address - the string to be scanned
        index - the beginning index (inclusive)
        end - the ending index (exclusive)
        counter - a counter for the number of 16-bit sections read in the address
        Returns:
        the index of the next character to scan, or -1 if the string cannot match a valid IPv6 address
      • isDigit

        private static boolean isDigit​(char chr)
        Determine whether a char is a digit.
        Returns:
        true if the char is betweeen '0' and '9', false otherwise
      • isHex

        private static boolean isHex​(char ch)
        Determine whether a character is a hexadecimal character.
        Returns:
        true if the char is betweeen '0' and '9', 'a' and 'f' or 'A' and 'F', false otherwise
      • isAlpha

        private static boolean isAlpha​(char ch)
        Determine whether a char is an alphabetic character: a-z or A-Z
        Returns:
        true if the char is alphabetic, false otherwise
      • isAlphanum

        private static boolean isAlphanum​(char ch)
        Determine whether a char is an alphanumeric: 0-9, a-z or A-Z
        Returns:
        true if the char is alphanumeric, false otherwise
      • isURICharacter

        private static boolean isURICharacter​(char ch)
        Determine whether a char is a URI character (reserved or unreserved, not including '%' for escaped octets).
        Returns:
        true if the char is a URI character, false otherwise
      • isSchemeCharacter

        private static boolean isSchemeCharacter​(char ch)
        Determine whether a char is a scheme character.
        Returns:
        true if the char is a scheme character, false otherwise
      • isUserinfoCharacter

        private static boolean isUserinfoCharacter​(char ch)
        Determine whether a char is a userinfo character.
        Returns:
        true if the char is a userinfo character, false otherwise
      • isPathCharacter

        private static boolean isPathCharacter​(char ch)
        Determine whether a char is a path character.
        Returns:
        true if the char is a path character, false otherwise
      • isURIString

        private static boolean isURIString​(java.lang.String 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.
        Returns:
        true if the string is comprised of uric, false otherwise