The interface for the URI(Uniform Resource Identifiers) version of RFC 2396. This class has the purpose of supportting of parsing a URI reference to extend any specific protocols, the character encoding of the protocol to be transported and the charset of the document.

A URI is always in an "escaped" form, since escaping or unescaping a completed URI might change its semantics.

Implementers should be careful not to escape or unescape the same string more than once, since unescaping an already unescaped string might lead to misinterpreting a percent data character as another escaped character, or vice versa in the case of escaping an already escaped string.

In order to avoid these problems, data types used as follows:

   URI character sequence: char
   octet sequence: byte
   original character sequence: String
 

So, a URI is a sequence of characters as an array of a char type, which is not always represented as a sequence of octets as an array of byte.

URI Syntactic Components

 - In general, written as follows:
   Absolute URI = <scheme>:<scheme-specific-part>
   Generic URI = <scheme>://<authority><path>?<query>

 - Syntax
   absoluteURI   = scheme ":" ( hier_part | opaque_part )
   hier_part     = ( net_path | abs_path ) [ "?" query ]
   net_path      = "//" authority [ abs_path ]
   abs_path      = "/"  path_segments
 

The following examples illustrate URI that are in common use.

 ftp://ftp.is.co.za/rfc/rfc1808.txt
    -- ftp scheme for File Transfer Protocol services
 gopher://spinaltap.micro.umn.edu/00/Weather/California/Los%20Angeles
    -- gopher scheme for Gopher and Gopher+ Protocol services
 http://www.math.uio.no/faq/compression-faq/part1.html
    -- http scheme for Hypertext Transfer Protocol services
 mailto:mduerst@ifi.unizh.ch
    -- mailto scheme for electronic mail addresses
 news:comp.infosystems.www.servers.unix
    -- news scheme for USENET news groups and articles
 telnet://melvyl.ucop.edu/
    -- telnet scheme for interactive services via the TELNET Protocol
 

Please, notice that there are many modifications from URL(RFC 1738) and relative URL(RFC 1808).

The expressions for a URI

 For escaped URI forms
  - URI(char[]) // constructor
  - char[] getRawXxx() // method
  - String getEscapedXxx() // method
  - String toString() // method
 

 For unescaped URI forms
  - URI(String) // constructor
  - String getXXX() // method