linkparser.java

jspwiki source code,jspwiki source code

        return link;
    }


    private String require( StringTokenizer tok, String required )
            throws ParseException, NoSuchElementException
    {
        String s = tok.nextToken(required);
        if( !s.equals(required) )
        {
            throw new ParseException("expected '"+required+"' not '"+s+"'"); // I18N
        }
        return s;
    }


    /** 
     *  Returns true if the String <tt>s</tt> is completely
     *  composed of whitespace.
     * 
     *  @param s The string to check
     *  @return True, if "s" is all XML whitespace.
     */
    public static final boolean isSpace( String s )
    {
        for( int i = 0 ; i < s.length() ; i++ )
        {
            if( !isSpace( s.charAt(i)) ) return false;
        }
        return true;
    }


    /** 
     *  Returns true if char <tt>c</tt> is a member of
     *  <tt>S</tt> (space) [XML 1.1 production 3].
     *  
     *  @param c Character to check.
     *  @return True, if the character is an XML space.
     */
    public static final boolean isSpace( char c )
    {
        return
           0x20 == c    // SPACE
        || 0x0A == c    // LF
        || 0x0D == c    // CR
        || 0x09 == c    // TAB
        || 0x85 == c    // NEL
        || 0x2028 == c; // LS (line separator)
    }


    // .........................................................................


    /**
     *  Inner class serving as a struct containing the parsed
     *  components of a link.
     */
    public static class Link
    {
        private String            m_text;
        private String            m_ref = null;
        private int               m_interwikiPoint = -1;
        private List<Attribute>   m_attribs = null;

        /**
         *  Create a new Link with text but no reference.
         *  @param text The link text.
         *  @throws ParseException If the link text is illegal.
         */
        protected Link( String text ) throws ParseException
        {
            setText(text);
        }

        /**
         *  Create a new link with a given text and hyperlink (reference).
         *  
         *  @param text The link text.
         *  @param ref  The hypertext reference.
         *  @throws ParseException If the link text or reference are illegal.
         */
        protected Link( String text, String ref ) throws ParseException
        {
            setText(text);
            setReference(ref);
        }

        /**
         *  Sets the link text.
         *  
         *  @param text The link text.
         *  @throws ParseException If the text is illegal (e.g. null).
         */
        protected void setText( String text ) throws ParseException
        {
            if( text == null )
            {
                throw new ParseException("null link text");
            }
            m_text = text;
        }

        /**
         *  Returns the link text.
         *  
         *  @return Link text.
         */
        public String getText()
        {
            return m_text;
        }

        /**
         *  Sets the hypertext reference.  Typically, this is an URI or an interwiki link,
         *  or a wikilink.
         *  
         *  @param ref The reference.
         *  @throws ParseException If the reference is illegal.
         */
        protected void setReference( String ref ) throws ParseException
        {
            if( ref == null )
            {
                throw new ParseException("null link reference value");
            }
            m_ref = ref;
        }

        /**
         *  Returns true, if there is a reference.
         *  
         *  @return True, if there's a reference; false otherwise.
         */
        public boolean hasReference()
        {
            return m_ref != null;
        }

        /** 
         *  Returns the link reference, or the link text if null. 
         *  
         *  @return A link reference.
         */
        public String getReference()
        {
            return m_ref != null
                    ? m_ref
                    : m_text ;
        }

        /**
         *  Returns true, if this Link represents an InterWiki link (of the form wiki:page).
         * 
         *  @return True, if this Link represents an InterWiki link.
         */
        public boolean isInterwikiLink()
        {
            if( !hasReference() ) m_ref = m_text;

            m_interwikiPoint = m_ref.indexOf(':');

            return m_interwikiPoint != -1;
        }

        /**
         *  Returns the name of the wiki if this is an interwiki link. 
         *  <pre>
         *    Link link = new Link("Foo","Wikipedia:Foobar");
         *    assert( link.getExternalWikiPage(), "Wikipedia" );
         *  </pre> 
         *  
         *  @return Name of the wiki, or null, if this is not an interwiki link.
         */
        public String getExternalWiki()
        {
            if( isInterwikiLink() )
            {
                return m_ref.substring( 0, m_interwikiPoint );
            }
            
            return null;
        }

        /** 
         *  Returns the wikiname part of an interwiki link. Used only with interwiki links.
         *  <pre>
         *    Link link = new Link("Foo","Wikipedia:Foobar");
         *    assert( link.getExternalWikiPage(), "Foobar" );
         *  </pre> 
         *  
         *  @return Wikiname part, or null, if this is not an interwiki link.
         */
        public String getExternalWikiPage()
        {
            if( isInterwikiLink() )
            {
                return m_ref.substring( m_interwikiPoint+1 );
            }
            
            return null;
        }

        /**
         *  Returns the number of attributes on this link.
         *  
         *  @return The number of attributes.
         */
        public int attributeCount()
        {
            return m_attribs != null
                    ? m_attribs.size()
                    : 0 ;
        }

        /**
         *  Adds another attribute to the link.
         *  
         *  @param attr A JDOM Attribute.
         */
        public void addAttribute( Attribute attr )
        {
            if( m_attribs == null )
            {
                m_attribs = new ArrayList<Attribute>();
            }
            m_attribs.add(attr);
        }

        /** 
         *  Returns an Iterator over the list of JDOM Attributes.
         *  
         *  @return Iterator over the attributes.
         */
        public Iterator getAttributes()
        {
            return m_attribs != null
                    ? m_attribs.iterator()
                    : m_EMPTY.iterator() ;
        }

        /** 
         *  Returns a wikitext string representation of this Link. 
         *  @return WikiText.
         */
        public String toString()
        {
            StringBuffer sb = new StringBuffer();
            sb.append( '[' );
            sb.append( m_text );

            if( m_ref != null )
            {
                sb.append( ' ' );
                sb.append( '|' );
                sb.append( ' ' );
                sb.append( m_ref );
            }

            if( m_attribs != null )
            {
                sb.append( ' ' );
                sb.append( '|' );
                Iterator it = getAttributes();
                while ( it.hasNext() )
                {
                    Attribute a = (Attribute)it.next();
                    sb.append( ' ' );
                    sb.append( a.getName() );
                    sb.append( '=' );
                    sb.append( '\'' );
                    sb.append( a.getValue() );
                    sb.append( '\'' );
                }
            }
            sb.append( ']' );
            return sb.toString();
        }

    } // end inner class

}