Class TokenQueue


  • public class TokenQueue
    extends Object
    A character queue with parsing helpers.
    Author:
    Jonathan Hedley
    • Constructor Detail

      • TokenQueue

        public TokenQueue​(String data)
        Create a new TokenQueue.
        Parameters:
        data - string of data to back queue.
    • Method Detail

      • isEmpty

        public boolean isEmpty()
        Is the queue empty?
        Returns:
        true if no data left in queue.
      • peek

        public char peek()
        Retrieves but does not remove the first character from the queue.
        Returns:
        First character, or 0 if empty.
      • addFirst

        public void addFirst​(Character c)
        Add a character to the start of the queue (will be the next character retrieved).
        Parameters:
        c - character to add
      • addFirst

        public void addFirst​(String seq)
        Add a string to the start of the queue.
        Parameters:
        seq - string to add.
      • matches

        public boolean matches​(String seq)
        Tests if the next characters on the queue match the sequence. Case insensitive.
        Parameters:
        seq - String to check queue for.
        Returns:
        true if the next characters match.
      • matchesCS

        public boolean matchesCS​(String seq)
        Case sensitive match test.
        Parameters:
        seq - string to case sensitively check for
        Returns:
        true if matched, false if not
      • matchesAny

        public boolean matchesAny​(String... seq)
        Tests if the next characters match any of the sequences. Case insensitive.
        Parameters:
        seq - list of strings to case insensitively check for
        Returns:
        true of any matched, false if none did
      • matchesAny

        public boolean matchesAny​(char... seq)
      • matchesStartTag

        public boolean matchesStartTag()
      • matchChomp

        public boolean matchChomp​(String seq)
        Tests if the queue matches the sequence (as with match), and if they do, removes the matched string from the queue.
        Parameters:
        seq - String to search for, and if found, remove from queue.
        Returns:
        true if found and removed, false if not found.
      • matchesWhitespace

        public boolean matchesWhitespace()
        Tests if queue starts with a whitespace character.
        Returns:
        if starts with whitespace
      • matchesWord

        public boolean matchesWord()
        Test if the queue matches a word character (letter or digit).
        Returns:
        if matches a word character
      • advance

        public void advance()
        Drops the next character off the queue.
      • consume

        public char consume()
        Consume one character off queue.
        Returns:
        first character on queue.
      • consume

        public void consume​(String seq)
        Consumes the supplied sequence of the queue. If the queue does not start with the supplied sequence, will throw an illegal state exception -- but you should be running match() against that condition.

        Case insensitive.

        Parameters:
        seq - sequence to remove from head of queue.
      • consumeTo

        public String consumeTo​(String seq)
        Pulls a string off the queue, up to but exclusive of the match sequence, or to the queue running out.
        Parameters:
        seq - String to end on (and not include in return, but leave on queue). Case sensitive.
        Returns:
        The matched data consumed from queue.
      • consumeToIgnoreCase

        public String consumeToIgnoreCase​(String seq)
      • consumeToAny

        public String consumeToAny​(String... seq)
        Consumes to the first sequence provided, or to the end of the queue. Leaves the terminator on the queue.
        Parameters:
        seq - any number of terminators to consume to. Case insensitive.
        Returns:
        consumed string
      • chompTo

        public String chompTo​(String seq)
        Pulls a string off the queue (like consumeTo), and then pulls off the matched string (but does not return it).

        If the queue runs out of characters before finding the seq, will return as much as it can (and queue will go isEmpty() == true).

        Parameters:
        seq - String to match up to, and not include in return, and to pull off queue. Case sensitive.
        Returns:
        Data matched from queue.
      • chompToIgnoreCase

        public String chompToIgnoreCase​(String seq)
      • chompBalanced

        public String chompBalanced​(char open,
                                    char close)
        Pulls a balanced string off the queue. E.g. if queue is "(one (two) three) four", (,) will return "one (two) three", and leave " four" on the queue. Unbalanced openers and closers can be quoted (with ' or ") or escaped (with \). Those escapes will be left in the returned string, which is suitable for regexes (where we need to preserve the escape), but unsuitable for contains text strings; use unescape for that.
        Parameters:
        open - opener
        close - closer
        Returns:
        data matched from the queue
      • unescape

        public static String unescape​(String in)
        Unescape a \ escaped string.
        Parameters:
        in - backslash escaped string
        Returns:
        unescaped string
      • consumeWhitespace

        public boolean consumeWhitespace()
        Pulls the next run of whitespace characters of the queue.
        Returns:
        Whether consuming whitespace or not
      • consumeWord

        public String consumeWord()
        Retrieves the next run of word type (letter or digit) off the queue.
        Returns:
        String of word characters from queue, or empty string if none.
      • consumeTagName

        public String consumeTagName()
        Consume an tag name off the queue (word or :, _, -)
        Returns:
        tag name
      • consumeElementSelector

        public String consumeElementSelector()
        Consume a CSS element selector (tag name, but | instead of : for namespaces (or *| for wildcard namespace), to not conflict with :pseudo selects).
        Returns:
        tag name
      • consumeCssIdentifier

        public String consumeCssIdentifier()
        Consume a CSS identifier (ID or class) off the queue (letter, digit, -, _) http://www.w3.org/TR/CSS2/syndata.html#value-def-identifier
        Returns:
        identifier
      • consumeAttributeKey

        public String consumeAttributeKey()
        Consume an attribute key off the queue (letter, digit, -, _, :")
        Returns:
        attribute key
      • remainder

        public String remainder()
        Consume and return whatever is left on the queue.
        Returns:
        remained of queue.