}

    /**
     * Skips characters. This method will block until some characters are available, an I/O error occurs, or the end of
     * the stream is reached.
     *
     * @param n The number of characters to skip
     * @return the number of characters actually skipped
     * @throws IllegalArgumentException If <code>n</code> is negative.
     * @throws IOException              If an I/O error occurs
     */
    public long skip( long n )
        throws IOException
    {
        if ( n < 0L )
        {
            throw new IllegalArgumentException( "skip value is negative" );
        }

        for ( long i = 0; i < n; i++ )
        {
            if ( read() == -1 )
            {
                return i;
            }
        }
        return n;
    }

    /**
     * Reads characters into a portion of an array. This method will block until some input is available, an I/O error
     * occurs, or the end of the stream is reached.
     *
     * @param cbuf Destination buffer to write characters to. Must not be <code>null</code>.
     * @param off  Offset at which to start storing characters.
     * @param len  Maximum number of characters to read.
     * @return the number of characters read, or -1 if the end of the stream has been reached
     * @throws IOException If an I/O error occurs
     */
    public int read( char cbuf[], int off, int len )
        throws IOException
    {
        for ( int i = 0; i < len; i++ )
        {
            int ch = read();
            if ( ch == -1 )
            {
                if ( i == 0 )
                {
                    return -1;
                }
                else
                {
                    return i;
                }
            }
            cbuf[off + i] = (char) ch;
        }
        return len;
    }

    /**
     * Returns the next character in the filtered stream, replacing tokens from the original stream.
     *
     * @return the next character in the resulting stream, or -1 if the end of the resulting stream has been reached
     * @throws IOException if the underlying stream throws an IOException during reading
     */
    public int read()
        throws IOException
    {
        if ( replaceIndex > 0 )
        {
            return replaceData.charAt( replaceData.length() - ( replaceIndex-- ) );
        }
        if ( eof )
        {
            return -1;
        }

        in.mark( markLength );

        int ch = in.read();
        if ( ( ch == -1 ) || ( ch == '\n' && !supportMultiLineFiltering ) )
        {
            return ch;
        }

        boolean inEscape = ( useEscape && ch == escapeString.charAt( 0 ) );

        StringBuffer key = new StringBuffer();

        // have we found an escape string?
        if ( inEscape )
        {
            for ( int i = 0; i < escapeString.length(); i++ )
            {
                key.append( (char) ch );

                if ( ch != escapeString.charAt( i ) || ch == -1 || ( ch == '\n' && !supportMultiLineFiltering ) )
                {
                    // mismatch, EOF or EOL, no escape string here
                    in.reset();
                    inEscape = false;
                    key.setLength( 0 );
                    break;
                }

                ch = in.read();

            }

        }

        }

        // write away the value if present, otherwise the key unmodified
        if ( value != null )
        {
            replaceData = value;
            replaceIndex = value.length();
        }
        else
        {
            replaceData = key.toString();
            replaceIndex = key.length();
        }

        if ( ch == -1 )
        {
            eof = true;
        }
        return read();

    }

    public boolean isInterpolateWithPrefixPattern()
    {
        return interpolateWithPrefixPattern;
    }

    public void setInterpolateWithPrefixPattern( boolean interpolateWithPrefixPattern )
    {
        this.interpolateWithPrefixPattern = interpolateWithPrefixPattern;
    }

    public String getEscapeString()
    {
        return escapeString;
    }

    public void setEscapeString( String escapeString )
    {
        // TODO NPE if escapeString is null ?
        if ( escapeString != null && escapeString.length() >= 1 )
        {
            this.escapeString = escapeString;
            this.useEscape = escapeString != null && escapeString.length() >= 1;
            calculateMarkLength();
        }
    }

    public boolean isPreserveEscapeString()
    {
        return preserveEscapeString;
    }

    public void setPreserveEscapeString( boolean preserveEscapeString )
    {
        this.preserveEscapeString = preserveEscapeString;
    }

    public RecursionInterceptor getRecursionInterceptor()
    {
        return recursionInterceptor;
    }

    public InterpolatorFilterReaderLineEnding setRecursionInterceptor( RecursionInterceptor recursionInterceptor )

        if ( !foundToken )
        {

            in.reset();
            return in.read();

        }

        // we're committed, find the end token, EOL or EOF

        key.append( beginToken );
        in.reset();
        in.skip( beginToken.length() );
        ch = in.read();

        int endTokenSize = endToken.length();
        int end = endTokenSize;
        do
        {
            if ( ch == -1 )
            {
                break;
            }
            else if ( ch == '\n' && !supportMultiLineFiltering )
            {
                // EOL
                key.append( (char) ch );
                break;
            }

            key.append( (char) ch );

            if ( ch == this.endToken.charAt( endTokenSize - end ) )
            {
                end--;
                if ( end == 0 )
                {
                    break;
                }
            }
            else
            {
                end = endTokenSize;
            }

            ch = in.read();
        }
        while ( true );